Your Kraft faced fiberglass bats are adding to your problem. The Kraft facing is a vapor barrier. Your spray foam is a vapor barrier. That means you have a double vapor barrier!
Agree! Double vapor barrier the primary issue here not insufficient foam. Think its less likely that vapor is condensing due to a large delta between outside temp and inboard foam surface. If there was a significant delta I'd expect condensation to be further inboard of the foam perhaps even on the shiplap. This is not the case which makes trapped vapor the probable culprit. Great catch!
This problem is not just associated with the Pole Barn construction method. It may be exacerbated by the metal siding that will offer no R-Value as compared to OSB sheeting and wood or Vinyl siding used on conventional construction. The issue is that the foam insulation on the outer walls was not sufficient to prevent the inner foam surface from going below the dew point that allowed internal condensation. The very very cold weather that we have experienced recently has tested the insulation and proven that it was deficient. If the weather had been warmer this year, you may have not have noticed the problem until a very cold season. Then the solution may have been more extensive due to the complete finishing of the interior. Now you have the opportunity to fix this and rest easy for years to come. Thank you for the explanation of the problem and taking personal responsibility. I am sure that you have helped many DIY builders avoid this problem.
My wife and I want to build a pole barn building for our 5th wheel and live in it during our retirement days coming up in one year . Your honesty is HART felt you are saving us from disaster and believe me at age 68 we couldn't handle it . So God Bless you for your honesty and I promise to send prayers your way 🙏
I built my own place back in 2006, and put a lot of research into this. I ended up doing rockwool batts and plastic vapor barrier. We live in climate with -40'C winters. In my opinion, the problem with spray foam is it sets the vapor barrier at the very outside of the structure, sealing any outside air from potentially drying out any moisture that does end up in the insulation cavity. Air tight sounds good, and is good for efficiency, but in reality, there's always going to be those weak spots where moisture will somehow get in. I went against the grain, and even drilled extra holes for ventilation in the tops of the cavities. I now do renovation work, and watch the building code trying to compensate for making all our houses 'air tight'. Walls rotting out at bottom corners of windows and doors, mold forming in cavities, radon gas getting trapped and raising to toxic levels. All problems we didn't have when we let structures breathe. Properly running your HRV will help, in my opinion.
In Europe new houses are mega air tight. The air tight layer is always in the warm zone. Putting the barrier in a non porous or vapour impermeable insulating layer is asking for trouble.
I'm not an expert but I know a couple of things 1. you're absolutely right that the foam isn't thick enough, which causes the dew point to be between the fiberglass and the foam. 2. the metal wall means you want as little vapor barrier between the inside of the house and the spray foam. that means getting rid of the paper face on the fiberglass (after you fix the foam), and it also means you have to be very careful about how you finish the walls. you want vapor to move freely from the foam face to the interior of the house, and wood, drywall, and paint will all slow it down, so pick wall materials that are highly permeable. 3. this is likely worse on the colder sides of the house (north). you could consider insulating the exterior to pull the dew point even farther out. some rock wool or foam board with some cladding over top would help. not ideal since you put so much work into the walls already, but it would help. probably cheaper to just add a couple more inches of foam to the inside, though. 4. you're absolutely right about the HRV and the dehumidifier. you'll probably have to keep this kind of house (sealed cladding) dryer than the average house in the winter... maybe uncomfortably dry. 5. consider just paying the extra to ditch the fiberglass and just make the foam thicker. it will be a big financial hit, but it will have a higher likelihood of working than most other options because it will be less likely to condense in the first place, and it will also allow any condensation to evaporate back into the interior as quickly as possible since even un-faced fiberglass will be slower to allow condensation to evaporate. having thicker foam also means you don't have to be as careful with your wall materials and paint, you can just leave a gap at the top and bottom for air to flow behind your shiplap or drywall, since air flow over the surface of foam does not reduce its R value while air flow around fiberglass will knock it down some.
I keep coming back to your channel because of your open-heartedness, generosity, courageous good humor, and resilience in the face of adversity, so I feel your disappointment here really keenly. It's particularly a service, though, when you have bad news to tell, because, well, that's life. Hope the repairs go well and smoothly, and thanks for your willingness to share all of it.
3:05 "I didn't spray any of it, so this is not my fault......." She needs to put on the Greyhound uniform before she runs you over like that, Don!!!! :-p
So sorry y’all are dealing with this. Our friends at flip flop barn is having to move for mold. keep your heads up. You guys will get it figured out! Hope the guy will help you guys out!
While this sucks this happened to you, imagine all the people you're helping because of this! My husband really REALLY wants a pole barn house. We're going to test it out by building a pole barn garage. This information is so valuable. Even if we don't spray foam ourselves we'll know what to look out for now so we can tell if the job was done right! Thanks so much for sharing and I can't wait to see how to fix this!!
At least 2" closed cell foam is the only way to go. This will make your structure about 3X stronger. If you wish to further insulate, use Rockwool insulation. My uncle built his house inside his barn. So nice.
I agree with a number of other folks here. I do flash and batt using only Rockwool (Roxul) and no vapor barrier. Rockwool is more mold resistant and passes vapor back through the sheetrock into the living space. I also agree that it would probably be a good idea to do the north face of the building in spray foam only with no batt insulation.
I probably should’ve watched your whole thing before I ended up commenting. But your air handler is not your problem spring light on the phone is not your problem your problem is that paper back insulation you have to get rid of the paper if you don’t get rid of that paper it doesn’t matter how much air you extract out of your house you’re going to have that Moisture trapped in between your two vapor barrier ‘s. You have to get rid of the paper backing
I just built a house. I have a similar problem. Some cells have a little moisture. I haven't rocked yet though, and I have plans for an r5 outside of the house. So I'm just letting it ride till then. It'll dry out, because I don't have any spray foam. Good luck guys. Don't panic there's always a solution!!
I was typing Spray Jones when you mentioned him. Just dry it out and spray thicker foam and don't even bother putting the batt unless its just to meet your R-value code
Seems like the spray foam with the vapor barrier insulation would be a double vapor barrier, trapping moisture between. I think best would be to just go full foam. The other option would be to use insulation without the vapor barrier or would it be better to use extra vapor barrier inside with a plastic sheet? It's basically sweating like a window on a cold day.
@@fortfun46835 Nope, if the foam is thick enough so that it's surface stays above dew point there will be no condensed moisture on the warm side of it. Doesn't matter if there is another vapor barrier inside of the foam. The added batt insulation will cool down the foam however.
The only difference between a good job in a bad job is the guy who takes the time and goes back in correct his mistakes as soon as he knows notices it you are doing a wonderful job, When God is with you who can be against you 😀
Similar comment I left for Marshall Remodel, from a building science perspective thinner spray foam (less that 2”) will shift the dew point to the backside of the spray foam creating a wet cavity especially in a cold climate vs having 2+” of spray foam and having the dew point inside the spray foam creating a dry/safe cavity. Resolution could be adding additional closed cell spray foam in order to eliminate the dew point issue. An ERV (although a great thing!) running is a mute point to an extent. warm inside air naturally can hold more moisture than cold air. When the warm air from inside touches the cold spray foam it condenses (moisture). Adding additional foam will raise the temperature of the backside of the foam creating a dry/safe cavity.
Had the same problem, since your house is super sealed up - all the moisture in the house from the concrete and drywall mud curing needs a place to go and will condense at the coldest areas, which are your exterior walls. When I got around to hooking up my HRV - it resolved the moisture issue in a few days. You are reaching the dew point at the spray-foam face. I am in Winnipeg, Canada where we deal with insulation/cold issues on a regular basis. Good Luck, very cool build, and very cool channel. I copied and pasted this same message to Mashall Remodel. Plus you are using a kraft-faced rolled insulation that might have a vapor barrier - that might cause the moisture to be trapped between your spray foam and the kraft paper/vapor barrier.
Don't feel bad or angry. There are very very few happy stories about building out your own home. My wife and I have been at it for 4+ years. Just remember there's one direction; forward!! Keep at it. You'll get there.
@@kashiefhenry830 Kashief, I live in West Texas. In summer, it is regularly over 100F. Often 107. It's also very dry here. Based on the research and working with builders, hvac companies, and research that I've done.....2 inches closed cell foam is THE minimum to put. I just put 2inches closed cell foam underneath my roof deck with open faced rockwool between the rafters and converting from vented attic to closed/conditioned attic. My roof is metal. Your situation may be a bit different with the c-container however, I would go 2in minimum and consider 3inches.
@coryjoe23 how's is that install working for you? I'm in west texas as well and I can't find any information on that type of install , metal roof and closed cell.
And this is why I WAS NOT going to try to install my spray foam myself. I priced it out and out here at least I'd only save $200. I hav watched a few other spray foam guys, and I know temperature can affect things too. The guys heated me shed pretty toasty and their foam was heated as well. BUT there were several areas they didn't get "good enough". A few that were only 1" thick, and a few where they didn't quite get behind the light receptacles. So this is an issue from moisture moving IN the house and not through the walls? Reading the comments reminded me of when the 6 of us llive in a camper through the dead of winter (-17 degrees F), heated by a propane furnace. So much moisture condensated that the windows would fill with water and I had to put towels out each night and ring out the water the next morning. Frost formed on the walls and our girls would wake u with their hair frozen to the walls! I hope you are able to figure something out that doesn't involve ripping the insulation out.
Such a bummer, but glad you caught it now at least. This is an extremely helpful video for us, so thanks for sharing your troubles. We were hoping to DIY closed cell foam on the inside of our roof, and we'll be watching closely as you fix the issue. Sorry you guys are dealing with this!
I know that you guys and others seem to having issues that are all related to spray foam but I had a very similar issue with using 1 inch polyiso foam on the exterior similar to the zipR sheating. It came down to the thermal transisition of temperature through the material and the interior mating surface of the foam against the fiberglass drops below the indoor dew point. You are on the right track that increasing the thickness of the foam may be a solution. This was the case for me by increasing the foam sheets to 2 inch xps solved my condensation issues. Also I kept my interior walls with drywall to allow any moisture that may be in the insulation to dry to the interior space. Keep up the investigation and hard work.
It's a pretty straightforward issue, which is that the surface of the foam in places hits temperatures below the dew point of the interior air. The issue is the ratio of insulation value between the batts which are air permeable and the foam which is not. If say the R value of each material is equal, then theoretically the temperature of the foam at the transition to fiberglass will be the average of the inside temperature and the outside temperature. So, if it's 70F inside, and 0F outside, the temperature in this scenario at the foam edge is 35F. Air at 70F that is at about 30% relative humidity or above will condense on anything that is below 37F. So, if the foam edge is 35F it will condense moisture. So, the ratio between the thicknesses of each insulation is critical, and you need to move the temperature of the foam inside edge to above any possible condensing scenario. You do that by adding more foam to make the foam edge warmer, or you add less batt insulation, which will also increase the foam edge temperature. The temperature calculation is basically linear, so if 2/3 of the insulation value is in the foam, the foam edge temperature will be 2/3 of the temperature differential between inside and outside. This assumes that air movement of heat isn't a big factor because everything is well sealed. A dew point chart will tell you what indoor moisture levels equate to what temperature targets you need to hit to prevent condensation.
That’s all a fine correct analysis, but irrelevant, because if the drywall was finished, there is no exposure to the warm interior air to condense. Do you see it?
@@joelandersonphoto That is not true. The moisture will diffuse thru the paint and drywall, just not as fast. So you might not notice it getting wet because it is a small amount, but it still gets wet. Vapor barriers are for that purpose, but in this case you don't want a cavity trapped between two of them, as it won't dry out. Some moisture will always get in. The solution will be to move the vapor barrier (surface of the foam) inward by adding more material until it is thick enough to keep it above the dew point. Removing the paper facing is a good idea too, but will make the dew point problem worse if they don't fix that.
Couple things I notice is you have a double vapor barrier. The spray foam and the paper on the insulation. Vapor will get trapped between the two in your walls. I'd suggest taking the tat paper off the batt insulation and install an ERV and even a whole house dehumidifier. We did 5" of open cell foam so there won't be any batt insulation. We did install an ERV and if needed I'll install a whole house dehumidifier after to keep the moisture in the house low. Good luck guys!
As others have mentioned. Increase the thickness of your foam and remove the paper from you fiberglass or install mineral wool instead of fiberglass. Also in an air tight house you MUST run your bath fan or HRV on high mode when taking a shower. I recommend a fan switch with a built in humidity sensor that auto starts the bath fan so you don't have to think about it.
Sorry this happened guys. Thank you for sharing this though. We're looking to do our own house in the future and knowing "what not to do" is just as important as "what to do." Good luck with the fix and keep up the good work!
Put up a pole barn 15 yrs ago, recently had a new garage door installed. Found out every crossmember is basically useless, condensation in that small gap did them in. Sad feeling for sure, live and learn lesson for sure. Garage is still standing without issue. Steel and Foam still has some structure to it I guess.
It's all good buddy..u found a problem before you're closed in and finished....all buildings are not perfect buddy.. materials ..weather and experience all can make a little difference...all the best ...UK builder x
It sucks I hate to here this I'm a spray foam contractor very important to get behind the studs for a continuing layer or Humidity will collect looks like u put alot of work actually its allot of work Spray Jones's is excellent information ☝️ foam kits are 1.7 pound density Not as much R value as contractor 2 pound closed cell foam so u need to be more thick to get same results actually costing more than contractor! Glad to hear you say It was just as expensive as it was to hire a professional so others know I've subscribe
You'll probably have to add more closed-cell spray foam. I always put 3 to 4 in in a wall 4 to 6 in the ceiling. You don't have to use fiberglass banded in the walls after. It's always nice if you got the room to put blowing cellulose in the Attic or your ceiling over top about 12 to 16 in you should be able to heat your house with a candle after the fact.
Oh you guys. My heart goes out. Human mistakes happen. I don't think anyone ever built a house without a few disasters. Water is harsh mistress to a home. Good luck!
HRU's are necessary for very tight homes ( Canadian building codes ), but they only slowly decrease humidity. You need a whole-house dehumidifier. get a hygrometer and check your relative humidity.
I'm so not used to these types of houses. Here we usually use thermal bricks (that have multiple air chambers, thus isolating thermically). Construction is simple: you lay the fundantion, then lay the bricks, you leave the open space where the pillars will be (made of concrete re-enforced with steel bars), you pour the concrete (pillars), install the windows, then on the exterior you cover the bricks with 10cm polistirene sheets or 10cm basalt insulation, then the finishing / exterior covering (nowadays based on silicone to protect from rain/water). On the interior you cover the bricks with a layer based on cement+lime, or equivalent products), then the finishing plastering, then color the walls. One man can do it if he wants to. No termites, insects, wet (thus useless) isolation, no health problems from inhaling (internal) fiberglass bats, no interior / exterior vapor barriers, those awful OSB sheets blackened with fungi from moist, etc. Personally I would make the walls from hemp (mixed with lime), especially if you make music. (they breath, remove extra moisture from inside, have acoustic properties, you can plaster directly on the walls, etc). And hemp grows without you even wanting it, thus it would normally cost little. But unfortunately after 1990 when joined in the US Empire, it all of a sudden became illegal.. (except for special cases which makes it expensive)
Find Spray Jones before you close up a wall. Also Dr. Joe's site is the best, the ultimate authority. A pro puts in two applications of 2" and more if metal or nails are showing. As one uses the house more and more, you get more vapor. So, stop dumping water into the air inside the house, do not use enamel paint, vent the wet areas like laundry/kitchen/bath areas. Weather and time will work against you so do it right now. Good luck. Bob in Nevada
Spray Jones discusses this in detail. Fiberglass insulation is very ineffective. If it was an employee you would fire it. Roxul is what I used. I am in Texas. I run a dehumidifier as a precautionary measure. I am in a converted shipping container.
Shtuff happens. Don't beat yourself up. I'm glad it wasn't too bad for you guys. Those dehumidifiers are great. We use one here at our cabin all the time due our rain forest environment. Good luck!
hope you guys got it fixed , I use to work at a box store with a certain color logo and did some research for customers, FrothPak 200 is for linier seals , like rim joints floor joist ect ect .. the Pak 210 is for the wall/ceiling insulation , a bit denser and sprays better .. even froth pak says this if you ask them , good luck hope this helps the next person wanting to use the pak200 vrs the 210 to save a buck .
Closed cell foam is a vapor barrier unto itself. Plus you have a paper vapor barrier. If cold gets in through your thin spots you have cold air stuck between two vapor barriers and it will condense.
I built a house 33 years ago following the Saskatchewan House Model. (University of Saskatchewan) The walls from the inside out are drywall, 2x4 with R12 open batts vapour barrier, sheathing, 3.5 inch space with R12, 2x4 with R12, Tyvek then brick. (there is 1/2 inch plywood top and bottom tying it all together. 1/3rd of the insulation is the house side of the vapour barrier and 2/3rds on the cold side. The 1/3rd 2/3rds keeps the vapour barrier above the dew point so there is no condensation on the house side of the vapour barrier. A bonus is all the plumbing and electrical are the house side of the vapour barrier making a much more air tight house.
You still need a vapor barrier like a 6 mil plastic on the interior walls before adding Sheetrock. Air exchange units can still bring humidity from the outside. A good vapor barrier will stop the moisture from the interior of the house to enter your walls.
If you live in a warm climate, the vapor barrier has to be installed outside, but in cold climates a vapor barrier is to be installed inside. Insulation is still permeable, although foil faced polyiso can act as a vapor barrier when the seams are taped and sealed and also adds to the r value of your wall. You need a non-permeable vapor barrier, and a 6 mil plastic will do the trick, but if you want to go the extra mile and add polyiso with the plastic...
Watch 3 spray foam problems under the Build channel with Matt Risinger. They added a vapor barrier outside because they live in a warm and humid climate.
A big bummer for sure but looking at the positive side it could have been much worse. You found it early rather than much later in the game and that's one to add to your many blessings in this little mountain life with a happy healthy wonderful family. Life goes on but now it's just asking a little more from ya...
I'm not a insulation expert!! Another thing I would research is close cell is a moisture barrier then you installed r19 with a moisture barrier trapping moisture in the middle like a sandwich. I have never seen flash and batt with moisture barrier on both sides. Good luck sorry for your troubles
We did 2" of spray foam on our roof with 10" of rockwool, and have had no issues with condensation (were averaging about 10° for our low and inside humidity at 23%). However we dis use zip sheathing, an air gap, then our metal roof so that may have made a difference. The mini splits will deffinately help de humidify, they also make bathroom vent fan switches that turn on automatically with certain amounts of humidity which may help (they've been working g great for us). Good luck getting this figured out, I know how it feels to tear out insulation (we had to do it on our build just not for the same reason).
Controlling the humidity is key. The lower the inside humidity the greater the temperature differential has to be to get condensation on the foam surface.
Not only did you not do 2” which make it a moisture barrier, you are applying your flash and bat with a vapor barrier on the opposite side of the closed spray foam. That creates an area for cold and warm air to meet and condense.
Dang Don, i was getting ready to do the same thing flash spray 1 inch and put 3 1/2 in walls . starting the pole barn in mid march. WOW, Thanks for the info. following.
Yeah don’t do that! Haha! Just use closed cell spray without fiberglass. If I had to start over I’d spray 4” closed cell in the walls and 6” in the ceiling.
It’s your outer metal siding that will cause the problem, if you go that route always leave the spray foam to the experts that know what your building needs, cost more but one and done
Don't forget the caulk between where you have two studs or two pieces of wood that are butt up next to each other. If you don't then you will get moisture penetrating your structure.
It's good to know what doesn't work well, thanks. Spray Jones is great. I think if I use the foam, for the little in price I will hire it out and go with 2 1/2" - 3" , no batts. I also noticed in his video his workers are always sticking in a probe to see the depth of spray
I have a sense energy monitor, it's expensive to buy but once it identifies your air exchange unit and dehumidifier you can set up custom alerts so you know when the unit has been running too long or off too long.
I feel for you making this discovery. It's fortunate that you hadn't finished covering all the walls. You might try to rig up some sort or light for your system so if it goes down or gets unplugged you will know. Bless you both as it's been a real lesson in patience for you.
All you can do is remove the face of your foil faced insulation. Right now you have moisture being trapped between 2 moisture barriers. Moisture will always be a problem. So you have everything you need atm. Your air exchange will alleviate any future problem as long as you remove that foil off your insulation.
I am finally after two-and-a-half years of living in a pole barn while building apartments to live in to keep tenants in my house I didn't use spray insulation I just used r19 I have nothing but wood heat in here as well as a pellet stove I rarely use unless it's really cold and I am in northern Idaho near Canada. I think because of the wood heat I have no problems with moisture in my walls I would have to spend my probably isn't quite as airtight as yours either
I am not a builder but we built our house and I will add once you get it done be sure to install a ERV or HRV depending on your climate. You'll need a way to exchange the air in that tight box that you now created. Otherwise, in winter you could get moisture in the house etc. Also much easier to install it now before you are done.
I guess you didn’t watch the whole video? 🙃 We touch on the HRV that we installed last year. We didn’t have that running at the time but in our case a dehumidifier is also needed. Yes an ERV or HRV is a must in a spray foamed building 👍 Thanks for watching!
The condensation is from the moisture in your home already, making contact with the cold outside wall. Just like a cold can of soda condensating outside on a warm humid day. Remember your walls are open to the indoor environment. Get done. Thx for sharing.
Appreciate the honesty with your situation. Some channels tend to only look at the positive and hide or cover up the negative. Stay positive and I hope things turn out ok.
Good for you that you did this video, others can learn from your experience. My experience with DIY sprayfoam is that it makes no sense what so ever compared to having a pro do the job for you. Unless you are restricted to doing small areas at a time, say room by room, you will get a better price and a better finished result by hiring a pro. Closed cell spray foam professionally applied should run you about a dollar per board foot which is the same as or less than the kit cost.
You have not sprayed over any flat horizontal 2x6 strappings holding the metal siding. Those are only 1.5 inch thick with R value of 1.8. To prevent moisture condensation, uninsulated lumber would have to be minimum 4 inches thick. Your fiberglass insulation does not help here because it lets the moisture to pass through and condensate on any surface that is cold enough. Take ordinary infrared thermometer, measure surface temperature of uninsulated horizontal strappings and compare it with surface temperature of surrounding spray foam. You will find that strappings surface is dramatically colder than surface of the spray foam. Those are exact locations around your house where water vapor condensates into the water droplets. Also make sure to run your HRV 24/7 to maintain acceptable moisture level.
During construction you're going to have moisture accumulating given the lack of conditoning of the air and the inherent moisture in the materials such as all the wood installed in the framing. A whole home dehumidifier coupled with your ERV/HRV is a solid solution. Given the flash and batt approach you should install a vapor barrier on the inside to make the system more robust lastly exterior rigid board would help move your condensing surfaces further away from the interior.
When I was deciding the insulation for my house im building. I considered DIY spray foam, tried a kit, then decided to hire the pro. Best decision, with all the factors considered. I also considered the flash, and batt, but after looking into it, I just went with all foam. In my case I did 2 inches closed cell, and the rest open cell. Hope I made the right choice...
You are absolutely correct in your problem. Theres a good website about building science and 2 inches of foam creates a vapor barrier but it’s very difficult spray 2 “ consistently most guys spray 3 only just for this reason that way if there are any light areas it will still be minimum of 2”. Also kudos on realizing interior moisture needs to be mitigated many homes we work on ask us why do we have moisture on the inside amd the answer is simple your humidity level is to high. One last thing to think about is how well the outside of your building is sealed. Spray foam is great and when done correctly you will have no problems however any small amount of air leaking in from the outside can still create a Cold meats hot issue behind the spray foam in between the sheeting and the outside. Spray foaming around wood still allows thermal bridging through the wood. For instance if you spray foam a wall cavity and don’t cover the stud and you have no exterior insulation at all I guarantee you the wood studs will still feel cold. Have of a thermal break on the outside makes your wall assembly that much better. Air sealing the outside as well as possible is just as important as proper spray foam. And so is exterior thermal breaks in the wall. Even a 1/2 of foam or depending on your wall assembly if you need it vapor open rockwool will help any potential thermal bridging issues. Safest easiest thing to do now is more spray foam. And I hate to say it fiberglass is the worst insulation much better off using rockwool. Better product all the way around. Best wishes I think your on the right track. I’m a builder up in Wisconsin we see these things all the time.
Sprayfoam is a thermal insulator but it also acts as a vapor barrier. Thermal insulation and vapor stop properties prevents condensation. Spotty application, thin application, thermal conductors and air passing through-> not good.
This is the first video of yours I've watched. As a student of building science I see you've done a lot of things right. "Flash and batt" is a fascinating idea, but there is a possibility of having condensation on the inside surface of the foam. I'm facing a similar challenge as I have a cabin in the Colorado Rockies I need to super-insulate. Fortunately moisture is extremely low at my altitude, so if I actively ventilate my long hot showers, controlling condensation within the walls is doable. I need to replace my siding, so I'll be insulating from the outside. Getting a good vapor barrier with faced fiberglass batts is almost impossible. The facing is fine, it's all those penetrations, plus the fact that no one tapes the seams. So my _real_ vapor barrier will be the foam insulation I add outside my fiberglass-insulated 2x4 walls. If I use one layer of 2-inch foil-faced polyiso, the temperature at the inside face could drop low enough for moisture to condense out of the air. However if I use 4-inch foil-faced polyiso, the inside surface temperature will remain high enough to prevent condensation. Practically speaking I'll be removing and replacing a few sheets of sheathing to get at some the wall cavities to diddle with wiring, otherwise I won't be touching the original exterior sheathing, wall cavities, or original fiberglass insulation. My 2-inch vs 4-inch question is a lot like your challenge to get uniform thickness in your closed-cell spray foam. Too thin and you get condensation. A critical aspect of building science is to never, never, never put two vapor barriers in a wall (or a ceiling). Not with a gap between them anyway. The entire thickness of closed-cell foam (or rigid foam boards) is the vapor barrier. Inside face or outside face, it's all vapor barrier. That said, you don't want faced fiberglass batts, but seriously, they don't do much good the way 99% of builders install them, so it's not a disaster if you reuse yours (unless you tape all your seams, seal around electrical boxes, etc). If I thought the existing "vapor barrier" in my wall was any good, I'd use something like rigid rockwool board insulation--decent insulation that breathes and is hydrophobic. Good luck with your fix. And get that ventilator working!
Dealt with something similar... Remove fiberglass to dry things out then replace fiberglass and do a proper vapour barrier inside. Your problem is that the the spray foam is acting as your vapour barrier but it is not on the innermost side of the wall. This causes condensation in places it cannot easily evaporate away. Plus more airflow inside is always good, hrv, dehumidifier etc
The foam insulation isn't thick enough. They have horizontal studs still showing. At R-1 per inch, those studs are causing a very cold wall that is causing condensation. they need to add at least 2 more inches of closed-cell foam.
I built my barndo home almost like this, my home is a sealed envelope also. When looking for a spray foam company I talked to 6 different ones and only one in my area ever mentioned closed cell foam but recommended putting 4” of open cell on top of the 2” of closed cell. Needless to say I didn’t go with this option in my walls, I have two layers of moisture barrier under my metal and then used RockWool insulation.. my roof also has 2 layers of moisture barrier under the metal and I used open cell spray foam on my roof and it is 12” thick. I was told by multiple people to never put closed cell foam on a roof bc of the problem you are having and you wouldn’t be able to pin point the issue. I also have a conditioned attic space meaning my HVAC unit is in my attic and it keeps the moisture controlled in my home and by doing this I also have all of my water lines in my conditioned attic space! I’m sorry you are having to deal with this issue but my opinion I would consider filling your entire wall cavity with open cell foam this should stop this issue.
Spray foam insulation itself acts as a vapor barrier. Faced Batt Insulation with a Vapor barrier creates a second Vapor barrier and can be damaging to walls in the case that water gets trapped inside the house. When the temperature difference is great enough, a house can “sweat.” If the vapor barrier prevents this moisture from escaping, it risks damaging the wood and integrity of the walls. Suggested Assembly: Spray Foam Insulation Unfaced Batt Insulation (to allow moisture to escape) ½” 0r 5/8” Gypsum Board Latex paint or vapor semi-permeable texture wall finish (to allow moisture to escape) Source: Building Science Corporation BSI-120: Understanding Walls* Joseph Lstiburek Figure 9: Wood Frame Assembly With Interior Cavity Insulation and Siding Description Figure 9 is a variation of Figure 8, where high-density closed-cell spray polyurethane foam (air-impermeable insulation) is installed on the interior surface of the exterior sheathing. Then, the remainder of the cavity is filled with fiberglass/cellulose/mineral fiber insulation (air-permeable insulation). The thickness or thermal resistance of the spray foam is based on climate zone and thickness of the wall framing (Table 3).
I thought the 2” spray foam recommendation was that you need 2” to get the proper vapor barrier. With a flash and batt method you are technically putting the vapor barrier on the wrong side for a cold climate. Like others have said, in order to avoid condensation, you need the foam to be thick enough to get the inside surface below the dew point when it’s at the coldest it is outside...it may not be just 2 inches...
Remove the fiberglass. Add more foam. 2 to 3 inches is the minimum for a vapor barrier. Don't use fiberglass insulation which is out of date but still commonly used, rather use Roxul(mineral wool) that doesn't have a vapor barrier, and is essentially fireproof.
I think the main issue is that you have a vapor barrier in the fiberglass too… you don’t need that. Just spray foam and normal fiberglass insolation or rock wool.
My installer filled the cavity completely with spray foam. His claim was that 4 inches of closed cell spray foam was an effective vapor barrier, but that the cavity had to be full to prevent convection within the cavity which would create condensation. He oversprayed and trimmed the foam flush with a bread knife type tool so drywall would fit flush. We were renovating a balloon framed 110 year old house. Have had zero issues with condensation after 8 years. In Canada or any cold climate you need a vapor barrier on the inside even with an air exchanger. You could also consider roxul type insulation that won't hold water and mildew, but still need a vapor barrier inside. If you don't have the 4 inches of foam, here 10 mil plastic is installed to act as the vapor barrier. Good luck.
Get rid of all fiberglass bat insulation! Add another inch of closed cell foam to the existing wall foam and flash the sides of the studs. Leave the balance of the wall cavity open so that none of the insulation surfaces drop down to the dewpoint.
Here's what I commented on Marshall Remodel's video: "No vapor barrier behind the sheetrock means all moisture from the interior air was condensing on the relatively cold spray foam, which does not permeate moisture. However, you can't have two vapor barriers. Seems like the only solutions would be either spray foam the whole wall cavity (very expensive) or do the traditional insulation + vapor barrier behind sheetrock without any spray foam. Also, curious if any HRV/ERV was being used?" I'm especially interested in these situations because I was planning on doing the *exact* same thing; pole building with 2-3in spray foam plus batting. Now I'm thinking the best option would be high quality house wrap sealed as best as possible with rockwool batting and a normal vapor barrier behind the sheetrock. Also, very sorry to hear about your troubles and *thank you* for sharing so much valuable information!!
You made the most knowledgeable comment. I told the guy at Marshall he needed a vapor barrier. That’s how most people do it in Alaska. He did comment back to me that the foam acted as a vapor barrier. It never made sense to me. As you recommended an HRV, house wrap (Tyvek) and a standard vapor barrier, seems like a good way to go, but it is different for many regions of the country. I’d like a pole barn house too because of the perceived cost savings, but first I will hire someone who knows weatherization and wall assemblies and figure out the degree days where I live and dew point.
@@Erik_MN Sounds like a good plan. I see Rockwool makes an R23 for 2x6 walls. With the VB I always use Acoustical chalk known as Black Death. Any joints are not just overlapped, they are French rolled, same with ceiling and also adher to the bottom place. In colder climates you can attach 2x4's on the warm side of the VB and use 24" R11 for a R34 wall. This give you a wire and plumbing chase and make it less likely that sheetrock screws will go into the VP. Good luck!
@@MM-sf3rl Thanks for the suggestions. Am in MN and will need all the r value possible. Also thinking of doing R60 blown insulation in the attic, with a drop ceiling so the hvac is completely enclosed in the conditioned space.
@@Erik_MN R60 with cellulose is great. HVAC in the condition space will be better for the equipment. Have you heard of Degree Days. In Duluth there are 10,000 DD x .004 = R40; in Minneapolis 8383 DD x .004 = R33 (walls only). Also, I think people underinsualte the slab. R20 rigid foam is recommended for Anchorage, R43+ for Arctic Slope.
Before my foamed house was even finished we realized we had high humidity so we added a whole house dehumidifier and it solved the problem. With no air conditioning running and the house sealed up humidity builds up fast.
Try to keep a positive view of this. Clearly, it is better to have discovered this now than after the walls had been finished. Also when the heat and cooling are going they will remove moisture also not to mention the air exchanger. Remember some people do not even have a home so be thankful to be blessed with one even if it takes more time than you expected. ALso remember its love that makes a home not how the home is built.
You need enough foam insulation on the outside so the inside face of the foam is above the dew point after you have your inside insulation on. There are guides for this in different climates.
Spray foam is a good tool for an engineer to use when there is limited space (so dense insulation is needed), or when there are lots of air gaps that can't be filled any other way. For example, it is now best practice to use spray foam around all door and window frames. This video is one of the many examples of how it's not the best tool for do-it-yourselfers. Designing a wall assembly in general is very much above the pay grade of even professional builders. If something goes wrong in that wall, you can't easily get inside the spray foam to repair things, so the design needs to be double, triple, and quadruple checked by professionals to make sure everything is done right the first time. I'm glad all you had to do was just spray more foam.
Flash and batt itself is problematic in cold climate, it's not even just the issue with the low spots but the fact that the vapor non permeable layer is on the colder side of the batt insulation, My suggestion is to not use the fiber glass insulation it just cause potential issues. More foam would be the safest solution. Also you should make sure you take care of potential air leaks in the wall assembly, where the warm air can pass through it will bring moisture with it and at one point it will condensate, it's not even just what you see on the inside though.. the HRV will help but you still need to address the problem with the insulation. I'm not sure but it looks like you didn't cover the girls with foam? Which wouldn't be ideal too.
so basically the warm, moist air from the inside is moving through the batt insulation, meeting the foam that is impermeable and below the dewpoint of the air and then condensing on the foam?
@@rthoeny7 thanks, that is what I thought when I saw this video and the Marshall one he referred to. I guess it is about knowing what min foam thickness is needed to keep above the dewpoint for the interior temps and rh.
@@blackwellkrb yes, it's the same when dealing with exterior insulation, it needs to be in the right proportion to the internal insulation. I think flash and batt isn't that great, sure it's about cost, but with enough closed cell foam you easily get enough R value and it's over all simple and not causing you to deal with the worries of condensate accumulating in the fiberglass over time...
@@rthoeny7 if we figure 70F and 50rh, dewpoint is about 51F. Need enough insulation to keep the interior face of the sprayfoam above that temp or condensation will occur. Of course this will change with different indoor conditions but we humans like conditions around those numbers.
Do not use faced fiberglass. You are creating another vapor barrier trapping the moisture that the lack is spray foam created. Use unfaced fiberglass. Spray foam is a vabor barrier.
Thanks for all of the comments!
Here's our follow up video detailing our 'fix' for the moisture issues.
ruclips.net/video/mzcNLtexTf0/видео.html
Your Kraft faced fiberglass bats are adding to your problem. The Kraft facing is a vapor barrier. Your spray foam is a vapor barrier. That means you have a double vapor barrier!
I was just about to say the same thing. Bad bad idea to have two vapor barriers.
diy
This! Need to get rid of faces insulation.
Agree! Double vapor barrier the primary issue here not insufficient foam. Think its less likely that vapor is condensing due to a large delta between outside temp and inboard foam surface. If there was a significant delta I'd expect condensation to be further inboard of the foam perhaps even on the shiplap. This is not the case which makes trapped vapor the probable culprit. Great catch!
Yep
Sorry to see you guys dealing with an issue like this. Look forward to following along. We'll hopefully be giving an update on ours soon.
Yeah thanks.
Appreciate yall coming over. Never would've seen our issue if it wasn't for yall showing yours! Looking forward to your update!
This problem is not just associated with the Pole Barn construction method. It may be exacerbated by the metal siding that will offer no R-Value as compared to OSB sheeting and wood or Vinyl siding used on conventional construction. The issue is that the foam insulation on the outer walls was not sufficient to prevent the inner foam surface from going below the dew point that allowed internal condensation. The very very cold weather that we have experienced recently has tested the insulation and proven that it was deficient. If the weather had been warmer this year, you may have not have noticed the problem until a very cold season. Then the solution may have been more extensive due to the complete finishing of the interior. Now you have the opportunity to fix this and rest easy for years to come. Thank you for the explanation of the problem and taking personal responsibility. I am sure that you have helped many DIY builders avoid this problem.
My wife and I want to build a pole barn building for our 5th wheel and live in it during our retirement days coming up in one year . Your honesty is HART felt you are saving us from disaster and believe me at age 68 we couldn't handle it . So God Bless you for your honesty and I promise to send prayers your way 🙏
I built my own place back in 2006, and put a lot of research into this. I ended up doing rockwool batts and plastic vapor barrier. We live in climate with -40'C winters. In my opinion, the problem with spray foam is it sets the vapor barrier at the very outside of the structure, sealing any outside air from potentially drying out any moisture that does end up in the insulation cavity. Air tight sounds good, and is good for efficiency, but in reality, there's always going to be those weak spots where moisture will somehow get in. I went against the grain, and even drilled extra holes for ventilation in the tops of the cavities. I now do renovation work, and watch the building code trying to compensate for making all our houses 'air tight'. Walls rotting out at bottom corners of windows and doors, mold forming in cavities, radon gas getting trapped and raising to toxic levels. All problems we didn't have when we let structures breathe.
Properly running your HRV will help, in my opinion.
In Europe new houses are mega air tight. The air tight layer is always in the warm zone. Putting the barrier in a non porous or vapour impermeable insulating layer is asking for trouble.
If there was 2 inches of closed cell foam then the vapor barrier would be on the warm side.
Honesty/humility about a screw up on RUclips? This is a channel I can get behind.
haha. Thanks so much!
I'm not an expert but I know a couple of things
1. you're absolutely right that the foam isn't thick enough, which causes the dew point to be between the fiberglass and the foam.
2. the metal wall means you want as little vapor barrier between the inside of the house and the spray foam. that means getting rid of the paper face on the fiberglass (after you fix the foam), and it also means you have to be very careful about how you finish the walls. you want vapor to move freely from the foam face to the interior of the house, and wood, drywall, and paint will all slow it down, so pick wall materials that are highly permeable.
3. this is likely worse on the colder sides of the house (north). you could consider insulating the exterior to pull the dew point even farther out. some rock wool or foam board with some cladding over top would help. not ideal since you put so much work into the walls already, but it would help. probably cheaper to just add a couple more inches of foam to the inside, though.
4. you're absolutely right about the HRV and the dehumidifier. you'll probably have to keep this kind of house (sealed cladding) dryer than the average house in the winter... maybe uncomfortably dry.
5. consider just paying the extra to ditch the fiberglass and just make the foam thicker. it will be a big financial hit, but it will have a higher likelihood of working than most other options because it will be less likely to condense in the first place, and it will also allow any condensation to evaporate back into the interior as quickly as possible since even un-faced fiberglass will be slower to allow condensation to evaporate. having thicker foam also means you don't have to be as careful with your wall materials and paint, you can just leave a gap at the top and bottom for air to flow behind your shiplap or drywall, since air flow over the surface of foam does not reduce its R value while air flow around fiberglass will knock it down some.
Hello. Now that I have seen some inside pics, maybe another follow up would be good.
You are the man to go to for info. I've watched and subbed within the last week and you know your stuff !!
Seems to me all those furring strips need a coat the same thickness as the sheathing so as not to create a condensing surface.
@@audiobrad99 are those directly on the sheathing? Or no sheathing and directly at the back of the stud wall with siding?
Do whatever ''Spray Jones'' says to do. He's the man when it comes to spray foam.
I keep coming back to your channel because of your open-heartedness, generosity, courageous good humor, and resilience in the face of adversity, so I feel your disappointment here really keenly. It's particularly a service, though, when you have bad news to tell, because, well, that's life. Hope the repairs go well and smoothly, and thanks for your willingness to share all of it.
Brutally honest people
Got to admire you
3:05 "I didn't spray any of it, so this is not my fault......." She needs to put on the Greyhound uniform before she runs you over like that, Don!!!! :-p
hahaha! right! :P
I think a lot of people like your comment, Brian...
haha!
Just reinforces my suggestion that you have t-shirts made...... hahaha
So sorry y’all are dealing with this. Our friends at flip flop barn is having to move for mold. keep your heads up. You guys will get it figured out! Hope the guy will help you guys out!
Thanks y’all. I think we’ve got it figured out and are moving forward. 🙂
While this sucks this happened to you, imagine all the people you're helping because of this! My husband really REALLY wants a pole barn house. We're going to test it out by building a pole barn garage. This information is so valuable. Even if we don't spray foam ourselves we'll know what to look out for now so we can tell if the job was done right! Thanks so much for sharing and I can't wait to see how to fix this!!
At least 2" closed cell foam is the only way to go. This will make your structure about 3X stronger. If you wish to further insulate, use Rockwool insulation. My uncle built his house inside his barn. So nice.
I agree with a number of other folks here. I do flash and batt using only Rockwool (Roxul) and no vapor barrier. Rockwool is more mold resistant and passes vapor back through the sheetrock into the living space. I also agree that it would probably be a good idea to do the north face of the building in spray foam only with no batt insulation.
I probably should’ve watched your whole thing before I ended up commenting. But your air handler is not your problem spring light on the phone is not your problem your problem is that paper back insulation you have to get rid of the paper if you don’t get rid of that paper it doesn’t matter how much air you extract out of your house you’re going to have that Moisture trapped in between your two vapor barrier ‘s. You have to get rid of the paper backing
That paper backing is usually lined with a plastic or tar type substance.. Thin but is vapor barrier.
Not enough to get rid of the paper. The vapour barrier made by the 1" of foam (r6) is past the dew point of the wall.
@@AndyCollier That's right. The foam has to be thicker to move the dew point outside of the foam layer.
I just built a house. I have a similar problem. Some cells have a little moisture. I haven't rocked yet though, and I have plans for an r5 outside of the house. So I'm just letting it ride till then. It'll dry out, because I don't have any spray foam. Good luck guys. Don't panic there's always a solution!!
I was typing Spray Jones when you mentioned him. Just dry it out and spray thicker foam and don't even bother putting the batt unless its just to meet your R-value code
You got it!
Seems like the spray foam with the vapor barrier insulation would be a double vapor barrier, trapping moisture between. I think best would be to just go full foam. The other option would be to use insulation without the vapor barrier or would it be better to use extra vapor barrier inside with a plastic sheet? It's basically sweating like a window on a cold day.
@@fortfun46835 Nope, if the foam is thick enough so that it's surface stays above dew point there will be no condensed moisture on the warm side of it. Doesn't matter if there is another vapor barrier inside of the foam. The added batt insulation will cool down the foam however.
The only difference between a good job in a bad job is the guy who takes the time and goes back in correct his mistakes as soon as he knows notices it you are doing a wonderful job, When God is with you who can be against you 😀
If it hasn’t been done twice it hasn’t been done right.
Similar comment I left for Marshall Remodel, from a building science perspective thinner spray foam (less that 2”) will shift the dew point to the backside of the spray foam creating a wet cavity especially in a cold climate vs having 2+” of spray foam and having the dew point inside the spray foam creating a dry/safe cavity.
Resolution could be adding additional closed cell spray foam in order to eliminate the dew point issue. An ERV (although a great thing!) running is a mute point to an extent. warm inside air naturally can hold more moisture than cold air. When the warm air from inside touches the cold spray foam it condenses (moisture).
Adding additional foam will raise the temperature of the backside of the foam creating a dry/safe cavity.
Glad to see a sane answer.
It feels like a big setback but just remember how much you've done and all the other challenges you over came. You two have got this!
Had the same problem, since your house is super sealed up - all the moisture in the house from the concrete and drywall mud curing needs a place to go and will condense at the coldest areas, which are your exterior walls. When I got around to hooking up my HRV - it resolved the moisture issue in a few days. You are reaching the dew point at the spray-foam face. I am in Winnipeg, Canada where we deal with insulation/cold issues on a regular basis. Good Luck, very cool build, and very cool channel. I copied and pasted this same message to Mashall Remodel. Plus you are using a kraft-faced rolled insulation that might have a vapor barrier - that might cause the moisture to be trapped between your spray foam and the kraft paper/vapor barrier.
Don't feel bad or angry. There are very very few happy stories about building out your own home. My wife and I have been at it for 4+ years. Just remember there's one direction; forward!! Keep at it. You'll get there.
thanks!
DAYM THAT SUCKS to hear, TOTALLY AGREE Spray Jones Is a GREAT resource, hang tough you should be able to fix this.
Thanks :)
1" closed cell is a air barrier 2" is a vapor barrier. 3" gives you full r value. If you do 2" then you need an unfaced batt
It really depends on where you live - how cold it gets in the winter will determine the minimum thickness of closed cell spray foam
@@Mogman150 okay my climate is mostly hot. Can you help me out with what thickness you think I need for a shipping container home?
@@kashiefhenry830 Kashief, I live in West Texas. In summer, it is regularly over 100F. Often 107. It's also very dry here. Based on the research and working with builders, hvac companies, and research that I've done.....2 inches closed cell foam is THE minimum to put. I just put 2inches closed cell foam underneath my roof deck with open faced rockwool between the rafters and converting from vented attic to closed/conditioned attic. My roof is metal. Your situation may be a bit different with the c-container however, I would go 2in minimum and consider 3inches.
@coryjoe23 how's is that install working for you? I'm in west texas as well and I can't find any information on that type of install , metal roof and closed cell.
And this is why I WAS NOT going to try to install my spray foam myself. I priced it out and out here at least I'd only save $200. I hav watched a few other spray foam guys, and I know temperature can affect things too. The guys heated me shed pretty toasty and their foam was heated as well. BUT there were several areas they didn't get "good enough". A few that were only 1" thick, and a few where they didn't quite get behind the light receptacles.
So this is an issue from moisture moving IN the house and not through the walls? Reading the comments reminded me of when the 6 of us llive in a camper through the dead of winter (-17 degrees F), heated by a propane furnace. So much moisture condensated that the windows would fill with water and I had to put towels out each night and ring out the water the next morning. Frost formed on the walls and our girls would wake u with their hair frozen to the walls!
I hope you are able to figure something out that doesn't involve ripping the insulation out.
I can't imagine how you felt discovering this. Sending prayers of support your way
Thank you! 🙂
Sorry to hear that, but thank you for sharing! I have this coming eventually and need all the info I can get.
Thanks! Yeah our follow up video shows the 'fix'. Added more spray foam, removed the kraft paper, and better air management.
Such a bummer, but glad you caught it now at least. This is an extremely helpful video for us, so thanks for sharing your troubles. We were hoping to DIY closed cell foam on the inside of our roof, and we'll be watching closely as you fix the issue. Sorry you guys are dealing with this!
I'm not telling you what to do, but is it worth taking the chance of doing it yourself ? Does it save that much money, thank you.
I know that you guys and others seem to having issues that are all related to spray foam but I had a very similar issue with using 1 inch polyiso foam on the exterior similar to the zipR sheating. It came down to the thermal transisition of temperature through the material and the interior mating surface of the foam against the fiberglass drops below the indoor dew point. You are on the right track that increasing the thickness of the foam may be a solution. This was the case for me by increasing the foam sheets to 2 inch xps solved my condensation issues. Also I kept my interior walls with drywall to allow any moisture that may be in the insulation to dry to the interior space. Keep up the investigation and hard work.
Hugs ya'll! It can be fixed that's the good thing. I'm learning and I about died when I saw Marshall Remodel's video the other day.
It's a pretty straightforward issue, which is that the surface of the foam in places hits temperatures below the dew point of the interior air. The issue is the ratio of insulation value between the batts which are air permeable and the foam which is not. If say the R value of each material is equal, then theoretically the temperature of the foam at the transition to fiberglass will be the average of the inside temperature and the outside temperature. So, if it's 70F inside, and 0F outside, the temperature in this scenario at the foam edge is 35F. Air at 70F that is at about 30% relative humidity or above will condense on anything that is below 37F. So, if the foam edge is 35F it will condense moisture. So, the ratio between the thicknesses of each insulation is critical, and you need to move the temperature of the foam inside edge to above any possible condensing scenario. You do that by adding more foam to make the foam edge warmer, or you add less batt insulation, which will also increase the foam edge temperature. The temperature calculation is basically linear, so if 2/3 of the insulation value is in the foam, the foam edge temperature will be 2/3 of the temperature differential between inside and outside. This assumes that air movement of heat isn't a big factor because everything is well sealed. A dew point chart will tell you what indoor moisture levels equate to what temperature targets you need to hit to prevent condensation.
Thank you for that thorough explanation!!
And doesn’t the lack of a vapor barrier add to the problem?
That’s all a fine correct analysis, but irrelevant, because if the drywall was finished, there is no exposure to the warm interior air to condense. Do you see it?
This is like saying, we built half of a car, but it doesn’t run very well
@@joelandersonphoto That is not true. The moisture will diffuse thru the paint and drywall, just not as fast. So you might not notice it getting wet because it is a small amount, but it still gets wet. Vapor barriers are for that purpose, but in this case you don't want a cavity trapped between two of them, as it won't dry out. Some moisture will always get in. The solution will be to move the vapor barrier (surface of the foam) inward by adding more material until it is thick enough to keep it above the dew point. Removing the paper facing is a good idea too, but will make the dew point problem worse if they don't fix that.
Couple things I notice is you have a double vapor barrier. The spray foam and the paper on the insulation. Vapor will get trapped between the two in your walls. I'd suggest taking the tat paper off the batt insulation and install an ERV and even a whole house dehumidifier.
We did 5" of open cell foam so there won't be any batt insulation. We did install an ERV and if needed I'll install a whole house dehumidifier after to keep the moisture in the house low. Good luck guys!
Thanks! Yes, removing the kraft paper. :)
As others have mentioned. Increase the thickness of your foam and remove the paper from you fiberglass or install mineral wool instead of fiberglass. Also in an air tight house you MUST run your bath fan or HRV on high mode when taking a shower. I recommend a fan switch with a built in humidity sensor that auto starts the bath fan so you don't have to think about it.
Sorry this happened guys. Thank you for sharing this though. We're looking to do our own house in the future and knowing "what not to do" is just as important as "what to do." Good luck with the fix and keep up the good work!
Thanks :)
Put up a pole barn 15 yrs ago, recently had a new garage door installed. Found out every crossmember is basically useless, condensation in that small gap did them in. Sad feeling for sure, live and learn lesson for sure. Garage is still standing without issue. Steel and Foam still has some structure to it I guess.
It's all good buddy..u found a problem before you're closed in and finished....all buildings are not perfect buddy.. materials ..weather and experience all can make a little difference...all the best ...UK builder x
It sucks I hate to here this I'm a spray foam contractor
very important to get behind the studs for a continuing layer or
Humidity will collect looks like u put alot of work actually its allot of work
Spray Jones's is excellent information ☝️ foam kits are 1.7 pound density
Not as much R value as contractor 2 pound closed cell foam so u need to be more thick to get same results actually costing more than contractor!
Glad to hear you say It was just as expensive as it was to hire a professional so others know I've subscribe
I'm so sorry y'all. I hope the community here on RUclips can help y'all out. ❤
You'll probably have to add more closed-cell spray foam. I always put 3 to 4 in in a wall 4 to 6 in the ceiling. You don't have to use fiberglass banded in the walls after. It's always nice if you got the room to put blowing cellulose in the Attic or your ceiling over top about 12 to 16 in you should be able to heat your house with a candle after the fact.
Oh you guys. My heart goes out. Human mistakes happen. I don't think anyone ever built a house without a few disasters. Water is harsh mistress to a home. Good luck!
Thank you!
HRU's are necessary for very tight homes ( Canadian building codes ), but they only slowly decrease humidity. You need a whole-house dehumidifier. get a hygrometer and check your relative humidity.
I'm so not used to these types of houses. Here we usually use thermal bricks (that have multiple air chambers, thus isolating thermically). Construction is simple: you lay the fundantion, then lay the bricks, you leave the open space where the pillars will be (made of concrete re-enforced with steel bars), you pour the concrete (pillars), install the windows, then on the exterior you cover the bricks with 10cm polistirene sheets or 10cm basalt insulation, then the finishing / exterior covering (nowadays based on silicone to protect from rain/water). On the interior you cover the bricks with a layer based on cement+lime, or equivalent products), then the finishing plastering, then color the walls.
One man can do it if he wants to. No termites, insects, wet (thus useless) isolation, no health problems from inhaling (internal) fiberglass bats, no interior / exterior vapor barriers, those awful OSB sheets blackened with fungi from moist, etc.
Personally I would make the walls from hemp (mixed with lime), especially if you make music. (they breath, remove extra moisture from inside, have acoustic properties, you can plaster directly on the walls, etc). And hemp grows without you even wanting it, thus it would normally cost little. But unfortunately after 1990 when joined in the US Empire, it all of a sudden became illegal.. (except for special cases which makes it expensive)
Sorry for your moisture issues.
Kraft paper on your insulation will feed mold if moisture is ever an issue.
Good luck
Find Spray Jones before you close up a wall. Also Dr. Joe's site is the best, the ultimate authority. A pro puts in two applications of 2" and more if metal or nails are showing. As one uses the house more and more, you get more vapor. So, stop dumping water into the air inside the house, do not use enamel paint, vent the wet areas like laundry/kitchen/bath areas. Weather and time will work against you so do it right now. Good luck. Bob in Nevada
Spray Jones discusses this in detail. Fiberglass insulation is very ineffective. If it was an employee you would fire it. Roxul is what I used. I am in Texas. I run a dehumidifier as a precautionary measure. I am in a converted shipping container.
Yup. It is what it is. If I ever build another home I’d just spray and not use any fiberglass.
It will all work out. You guys keep the smiles!!!
Shtuff happens. Don't beat yourself up. I'm glad it wasn't too bad for you guys. Those dehumidifiers are great. We use one here at our cabin all the time due our rain forest environment. Good luck!
Thanks!! :)
Thanks for the lesson stay strong guys and great job sir took that like a champ
Thank you!
Thanks for posting this video. I’m currently researching steel buildings and building out a house inside. Insulation is one of my concerns.
Closed-cell foam is the only way to go at least 2" thick that will get you to R-14. I'd go to R-30
hope you guys got it fixed , I use to work at a box store with a certain color logo and did some research for customers, FrothPak 200 is for linier seals , like rim joints floor joist ect ect .. the Pak 210 is for the wall/ceiling insulation , a bit denser and sprays better .. even froth pak says this if you ask them , good luck hope this helps the next person wanting to use the pak200 vrs the 210 to save a buck .
Yup sprayed more and it’s all good.
Closed cell foam is a vapor barrier unto itself. Plus you have a paper vapor barrier. If cold gets in through your thin spots you have cold air stuck between two vapor barriers and it will condense.
I built a house 33 years ago following the Saskatchewan House Model. (University of Saskatchewan) The walls from the inside out are drywall, 2x4 with R12 open batts vapour barrier, sheathing, 3.5 inch space with R12, 2x4 with R12, Tyvek then brick. (there is 1/2 inch plywood top and bottom tying it all together. 1/3rd of the insulation is the house side of the vapour barrier and 2/3rds on the cold side. The 1/3rd 2/3rds keeps the vapour barrier above the dew point so there is no condensation on the house side of the vapour barrier. A bonus is all the plumbing and electrical are the house side of the vapour barrier making a much more air tight house.
You still need a vapor barrier like a 6 mil plastic on the interior walls before adding Sheetrock. Air exchange units can still bring humidity from the outside. A good vapor barrier will stop the moisture from the interior of the house to enter your walls.
If you live in a warm climate, the vapor barrier has to be installed outside, but in cold climates a vapor barrier is to be installed inside. Insulation is still permeable, although foil faced polyiso can act as a vapor barrier when the seams are taped and sealed and also adds to the r value of your wall. You need a non-permeable vapor barrier, and a 6 mil plastic will do the trick, but if you want to go the extra mile and add polyiso with the plastic...
Watch 3 spray foam problems under the Build channel with Matt Risinger. They added a vapor barrier outside because they live in a warm and humid climate.
Oh man guys, I am so sorry. I know you will get it fixed and things will work out. Take care.
Thank you 🙂
Thank you for your video. How did you manage the mold problem that this created?
We showed the process in a follow up video.
Essentially just added more spray foam to thicken up the low spots.
A big bummer for sure but looking at the positive side it could have been much worse. You found it early rather than much later in the game and that's one to add to your many blessings in this little mountain life with a happy healthy wonderful family. Life goes on but now it's just asking a little more from ya...
Thanks Chris!
I'm not a insulation expert!!
Another thing I would research is close cell is a moisture barrier then you installed r19 with a moisture barrier trapping moisture in the middle like a sandwich. I have never seen flash and batt with moisture barrier on both sides.
Good luck sorry for your troubles
Right. We addressed this in our follow up video. Thanks
We did 2" of spray foam on our roof with 10" of rockwool, and have had no issues with condensation (were averaging about 10° for our low and inside humidity at 23%). However we dis use zip sheathing, an air gap, then our metal roof so that may have made a difference.
The mini splits will deffinately help de humidify, they also make bathroom vent fan switches that turn on automatically with certain amounts of humidity which may help (they've been working g great for us).
Good luck getting this figured out, I know how it feels to tear out insulation (we had to do it on our build just not for the same reason).
Thank you. Definitely think the mini splits will help too.
Controlling the humidity is key. The lower the inside humidity the greater the temperature differential has to be to get condensation on the foam surface.
Not only did you not do 2” which make it a moisture barrier, you are applying your flash and bat with a vapor barrier on the opposite side of the closed spray foam. That creates an area for cold and warm air to meet and condense.
Dang Don, i was getting ready to do the same thing flash spray 1 inch and put 3 1/2 in walls . starting the pole barn in mid march. WOW, Thanks for the info. following.
Yeah don’t do that! Haha!
Just use closed cell spray without fiberglass. If I had to start over I’d spray 4” closed cell in the walls and 6” in the ceiling.
@@LittleMountainLife im so sorry, just horrible.
It’s your outer metal siding that will cause the problem, if you go that route always leave the spray foam to the experts that know what your building needs, cost more but one and done
Metal siding doesn't matter if the foam is sprayed thick enough.
Plenty of "experts" have screwed up spray foam...
Thanks for watching.
Don't forget the caulk between where you have two studs or two pieces of wood that are butt up next to each other. If you don't then you will get moisture penetrating your structure.
definitely!
It's good to know what doesn't work well, thanks. Spray Jones is great. I think if I use the foam, for the little in price I will hire it out and go with 2 1/2" - 3" , no batts. I also noticed in his video his workers are always sticking in a probe to see the depth of spray
Yeah best to just do all spray instead of flash and batt.
We show the fix in the follow up video.
I have a sense energy monitor, it's expensive to buy but once it identifies your air exchange unit and dehumidifier you can set up custom alerts so you know when the unit has been running too long or off too long.
Hahahaha I didn't spray any of it "Not my fault" 😂😂😂😂
3:05 EVERY married man in the world knows what this little exchange is like..😂😂😂 I know that deep breath afterwards...I know it well my brother.
I feel for you making this discovery. It's fortunate that you hadn't finished covering all the walls. You might try to rig up some sort or light for your system so if it goes down or gets unplugged you will know. Bless you both as it's been a real lesson in patience for you.
All you can do is remove the face of your foil faced insulation. Right now you have moisture being trapped between 2 moisture barriers. Moisture will always be a problem. So you have everything you need atm. Your air exchange will alleviate any future problem as long as you remove that foil off your insulation.
I am finally after two-and-a-half years of living in a pole barn while building apartments to live in to keep tenants in my house I didn't use spray insulation I just used r19 I have nothing but wood heat in here as well as a pellet stove I rarely use unless it's really cold and I am in northern Idaho near Canada. I think because of the wood heat I have no problems with moisture in my walls I would have to spend my probably isn't quite as airtight as yours either
I am not a builder but we built our house and I will add once you get it done be sure to install a ERV or HRV depending on your climate. You'll need a way to exchange the air in that tight box that you now created. Otherwise, in winter you could get moisture in the house etc. Also much easier to install it now before you are done.
I guess you didn’t watch the whole video? 🙃
We touch on the HRV that we installed last year. We didn’t have that running at the time but in our case a dehumidifier is also needed.
Yes an ERV or HRV is a must in a spray foamed building 👍
Thanks for watching!
@@LittleMountainLife you're right I didn't watch all of it.
The condensation is from the moisture in your home already, making contact with the cold outside wall. Just like a cold can of soda condensating outside on a warm humid day. Remember your walls are open to the indoor environment. Get done. Thx for sharing.
Appreciate the honesty with your situation. Some channels tend to only look at the positive and hide or cover up the negative. Stay positive and I hope things turn out ok.
Good for you that you did this video, others can learn from your experience. My experience with DIY sprayfoam is that it makes no sense what so ever compared to having a pro do the job for you. Unless you are restricted to doing small areas at a time, say room by room, you will get a better price and a better finished result by hiring a pro. Closed cell spray foam professionally applied should run you about a dollar per board foot which is the same as or less than the kit cost.
You have not sprayed over any flat horizontal 2x6 strappings holding the metal siding. Those are only 1.5 inch thick with R value of 1.8. To prevent moisture condensation, uninsulated lumber would have to be minimum 4 inches thick. Your fiberglass insulation does not help here because it lets the moisture to pass through and condensate on any surface that is cold enough.
Take ordinary infrared thermometer, measure surface temperature of uninsulated horizontal strappings and compare it with surface temperature of surrounding spray foam. You will find that strappings surface is dramatically colder than surface of the spray foam. Those are exact locations around your house where water vapor condensates into the water droplets.
Also make sure to run your HRV 24/7 to maintain acceptable moisture level.
During construction you're going to have moisture accumulating given the lack of conditoning of the air and the inherent moisture in the materials such as all the wood installed in the framing. A whole home dehumidifier coupled with your ERV/HRV is a solid solution. Given the flash and batt approach you should install a vapor barrier on the inside to make the system more robust lastly exterior rigid board would help move your condensing surfaces further away from the interior.
Hi, great videos. Can you share-what do you do with your canisters after use? It’s the great unanswered question with froth paks
When I was deciding the insulation for my house im building. I considered DIY spray foam, tried a kit, then decided to hire the pro. Best decision, with all the factors considered.
I also considered the flash, and batt, but after looking into it, I just went with all foam.
In my case I did 2 inches closed cell, and the rest open cell. Hope I made the right choice...
Yeah you made the right choice 👍
the open cell will breath unlike kraft paper
You are absolutely correct in your problem. Theres a good website about building science and 2 inches of foam creates a vapor barrier but it’s very difficult spray 2 “ consistently most guys spray 3 only just for this reason that way if there are any light areas it will still be minimum of 2”. Also kudos on realizing interior moisture needs to be mitigated many homes we work on ask us why do we have moisture on the inside amd the answer is simple your humidity level is to high. One last thing to think about is how well the outside of your building is sealed. Spray foam is great and when done correctly you will have no problems however any small amount of air leaking in from the outside can still create a Cold meats hot issue behind the spray foam in between the sheeting and the outside. Spray foaming around wood still allows thermal bridging through the wood. For instance if you spray foam a wall cavity and don’t cover the stud and you have no exterior insulation at all I guarantee you the wood studs will still feel cold. Have of a thermal break on the outside makes your wall assembly that much better. Air sealing the outside as well as possible is just as important as proper spray foam. And so is exterior thermal breaks in the wall. Even a 1/2 of foam or depending on your wall assembly if you need it vapor open rockwool will help any potential thermal bridging issues. Safest easiest thing to do now is more spray foam. And I hate to say it fiberglass is the worst insulation much better off using rockwool. Better product all the way around. Best wishes I think your on the right track. I’m a builder up in Wisconsin we see these things all the time.
Sprayfoam is a thermal insulator but it also acts as a vapor barrier. Thermal insulation and vapor stop properties prevents condensation. Spotty application, thin application, thermal conductors and air passing through-> not good.
The follow up video shows how we fixed the issue. Thanks for watching
This is the first video of yours I've watched. As a student of building science I see you've done a lot of things right. "Flash and batt" is a fascinating idea, but there is a possibility of having condensation on the inside surface of the foam.
I'm facing a similar challenge as I have a cabin in the Colorado Rockies I need to super-insulate. Fortunately moisture is extremely low at my altitude, so if I actively ventilate my long hot showers, controlling condensation within the walls is doable. I need to replace my siding, so I'll be insulating from the outside. Getting a good vapor barrier with faced fiberglass batts is almost impossible. The facing is fine, it's all those penetrations, plus the fact that no one tapes the seams. So my _real_ vapor barrier will be the foam insulation I add outside my fiberglass-insulated 2x4 walls.
If I use one layer of 2-inch foil-faced polyiso, the temperature at the inside face could drop low enough for moisture to condense out of the air. However if I use 4-inch foil-faced polyiso, the inside surface temperature will remain high enough to prevent condensation. Practically speaking I'll be removing and replacing a few sheets of sheathing to get at some the wall cavities to diddle with wiring, otherwise I won't be touching the original exterior sheathing, wall cavities, or original fiberglass insulation.
My 2-inch vs 4-inch question is a lot like your challenge to get uniform thickness in your closed-cell spray foam. Too thin and you get condensation.
A critical aspect of building science is to never, never, never put two vapor barriers in a wall (or a ceiling). Not with a gap between them anyway. The entire thickness of closed-cell foam (or rigid foam boards) is the vapor barrier. Inside face or outside face, it's all vapor barrier. That said, you don't want faced fiberglass batts, but seriously, they don't do much good the way 99% of builders install them, so it's not a disaster if you reuse yours (unless you tape all your seams, seal around electrical boxes, etc). If I thought the existing "vapor barrier" in my wall was any good, I'd use something like rigid rockwool board insulation--decent insulation that breathes and is hydrophobic.
Good luck with your fix. And get that ventilator working!
"Don Flooded The House" is the 2nd video for me to watch after this one...... get it together people.
Thanks for making videos.
Just sharing reality. Never claimed to have it 'together'. Haha!
Thanks for watching!
Dealt with something similar... Remove fiberglass to dry things out then replace fiberglass and do a proper vapour barrier inside. Your problem is that the the spray foam is acting as your vapour barrier but it is not on the innermost side of the wall. This causes condensation in places it cannot easily evaporate away. Plus more airflow inside is always good, hrv, dehumidifier etc
The foam insulation isn't thick enough. They have horizontal studs still showing. At R-1 per inch, those studs are causing a very cold wall that is causing condensation. they need to add at least 2 more inches of closed-cell foam.
I built my barndo home almost like this, my home is a sealed envelope also. When looking for a spray foam company I talked to 6 different ones and only one in my area ever mentioned closed cell foam but recommended putting 4” of open cell on top of the 2” of closed cell. Needless to say I didn’t go with this option in my walls, I have two layers of moisture barrier under my metal and then used RockWool insulation.. my roof also has 2 layers of moisture barrier under the metal and I used open cell spray foam on my roof and it is 12” thick. I was told by multiple people to never put closed cell foam on a roof bc of the problem you are having and you wouldn’t be able to pin point the issue. I also have a conditioned attic space meaning my HVAC unit is in my attic and it keeps the moisture controlled in my home and by doing this I also have all of my water lines in my conditioned attic space! I’m sorry you are having to deal with this issue but my opinion I would consider filling your entire wall cavity with open cell foam this should stop this issue.
Kalon, what part of the country are you located in?
Boothill of Missouri.
Spray foam insulation itself acts as a vapor barrier.
Faced Batt Insulation with a Vapor barrier creates a second Vapor barrier and can be damaging to walls in the case that water gets trapped inside the house. When the temperature difference is great enough, a house can “sweat.” If the vapor barrier prevents this moisture from escaping, it risks damaging the wood and integrity of the walls.
Suggested Assembly:
Spray Foam Insulation
Unfaced Batt Insulation (to allow moisture to escape)
½” 0r 5/8” Gypsum Board
Latex paint or vapor semi-permeable texture wall finish (to allow moisture to escape)
Source: Building Science Corporation
BSI-120: Understanding Walls*
Joseph Lstiburek
Figure 9: Wood Frame Assembly With Interior Cavity Insulation and Siding
Description Figure 9 is a variation of Figure 8, where high-density closed-cell spray polyurethane foam (air-impermeable insulation) is installed on the interior surface of the exterior sheathing. Then, the remainder of the cavity is filled with fiberglass/cellulose/mineral fiber insulation (air-permeable insulation). The thickness or thermal resistance of the spray foam is based on climate zone and thickness of the wall framing (Table 3).
I thought the 2” spray foam recommendation was that you need 2” to get the proper vapor barrier. With a flash and batt method you are technically putting the vapor barrier on the wrong side for a cold climate. Like others have said, in order to avoid condensation, you need the foam to be thick enough to get the inside surface below the dew point when it’s at the coldest it is outside...it may not be just 2 inches...
Exactly right
I think the horizontal 2x4's also need to be covered in the same thickness of foam, since they do not block heat as well as foam.
Remove the fiberglass. Add more foam. 2 to 3 inches is the minimum for a vapor barrier. Don't use fiberglass insulation which is out of date but still commonly used, rather use Roxul(mineral wool) that doesn't have a vapor barrier, and is essentially fireproof.
I think the main issue is that you have a vapor barrier in the fiberglass too… you don’t need that. Just spray foam and normal fiberglass insolation or rock wool.
My installer filled the cavity completely with spray foam. His claim was that 4 inches of closed cell spray foam was an effective vapor barrier, but that the cavity had to be full to prevent convection within the cavity which would create condensation. He oversprayed and trimmed the foam flush with a bread knife type tool so drywall would fit flush. We were renovating a balloon framed 110 year old house. Have had zero issues with condensation after 8 years. In Canada or any cold climate you need a vapor barrier on the inside even with an air exchanger. You could also consider roxul type insulation that won't hold water and mildew, but still need a vapor barrier inside. If you don't have the 4 inches of foam, here 10 mil plastic is installed to act as the vapor barrier. Good luck.
Get rid of all fiberglass bat insulation! Add another inch of closed cell foam to the existing wall foam and flash the sides of the studs. Leave the balance of the wall cavity open so that none of the insulation surfaces drop down to the dewpoint.
Here's what I commented on Marshall Remodel's video:
"No vapor barrier behind the sheetrock means all moisture from the interior air was condensing on the relatively cold spray foam, which does not permeate moisture. However, you can't have two vapor barriers. Seems like the only solutions would be either spray foam the whole wall cavity (very expensive) or do the traditional insulation + vapor barrier behind sheetrock without any spray foam. Also, curious if any HRV/ERV was being used?"
I'm especially interested in these situations because I was planning on doing the *exact* same thing; pole building with 2-3in spray foam plus batting. Now I'm thinking the best option would be high quality house wrap sealed as best as possible with rockwool batting and a normal vapor barrier behind the sheetrock.
Also, very sorry to hear about your troubles and *thank you* for sharing so much valuable information!!
You made the most knowledgeable comment. I told the guy at Marshall he needed a vapor barrier. That’s how most people do it in Alaska. He did comment back to me that the foam acted as a vapor barrier. It never made sense to me. As you recommended an HRV, house wrap (Tyvek) and a standard vapor barrier, seems like a good way to go, but it is different for many regions of the country. I’d like a pole barn house too because of the perceived cost savings, but first I will hire someone who knows weatherization and wall assemblies and figure out the degree days where I live and dew point.
Am also planning a house of this construction. Plan is Sheet metal > house wrap > rockwool insulation > vapor barrier > drywall
@@Erik_MN Sounds like a good plan. I see Rockwool makes an R23 for 2x6 walls. With the VB I always use Acoustical chalk known as Black Death. Any joints are not just overlapped, they are French rolled, same with ceiling and also adher to the bottom place. In colder climates you can attach 2x4's on the warm side of the VB and use 24" R11 for a R34 wall. This give you a wire and plumbing chase and make it less likely that sheetrock screws will go into the VP. Good luck!
@@MM-sf3rl Thanks for the suggestions. Am in MN and will need all the r value possible. Also thinking of doing R60 blown insulation in the attic, with a drop ceiling so the hvac is completely enclosed in the conditioned space.
@@Erik_MN R60 with cellulose is great. HVAC in the condition space will be better for the equipment. Have you heard of Degree Days. In Duluth there are 10,000 DD x .004 = R40; in Minneapolis 8383 DD x .004 = R33 (walls only). Also, I think people underinsualte the slab. R20 rigid foam is recommended for Anchorage, R43+ for Arctic Slope.
Before my foamed house was even finished we realized we had high humidity so we added a whole house dehumidifier and it solved the problem. With no air conditioning running and the house sealed up humidity builds up fast.
Try to keep a positive view of this. Clearly, it is better to have discovered this now than after the walls had been finished. Also when the heat and cooling are going they will remove moisture also not to mention the air exchanger. Remember some people do not even have a home so be thankful to be blessed with one even if it takes more time than you expected. ALso remember its love that makes a home not how the home is built.
Stay strong
Wouldn’t think there would be such a buildup in the dry winter air, wonder what summer will be like?
As vapor barrier on the inside?
You need enough foam insulation on the outside so the inside face of the foam is above the dew point after you have your inside insulation on. There are guides for this in different climates.
Correct. We addressed this and added more spray foam in the follow up video.
Thanks
Spray foam is a good tool for an engineer to use when there is limited space (so dense insulation is needed), or when there are lots of air gaps that can't be filled any other way. For example, it is now best practice to use spray foam around all door and window frames. This video is one of the many examples of how it's not the best tool for do-it-yourselfers. Designing a wall assembly in general is very much above the pay grade of even professional builders. If something goes wrong in that wall, you can't easily get inside the spray foam to repair things, so the design needs to be double, triple, and quadruple checked by professionals to make sure everything is done right the first time. I'm glad all you had to do was just spray more foam.
Flash and batt itself is problematic in cold climate, it's not even just the issue with the low spots but the fact that the vapor non permeable layer is on the colder side of the batt insulation, My suggestion is to not use the fiber glass insulation it just cause potential issues. More foam would be the safest solution. Also you should make sure you take care of potential air leaks in the wall assembly, where the warm air can pass through it will bring moisture with it and at one point it will condensate, it's not even just what you see on the inside though.. the HRV will help but you still need to address the problem with the insulation.
I'm not sure but it looks like you didn't cover the girls with foam? Which wouldn't be ideal too.
so basically the warm, moist air from the inside is moving through the batt insulation, meeting the foam that is impermeable and below the dewpoint of the air and then condensing on the foam?
@@blackwellkrb exactly that's what happened
@@rthoeny7 thanks, that is what I thought when I saw this video and the Marshall one he referred to. I guess it is about knowing what min foam thickness is needed to keep above the dewpoint for the interior temps and rh.
@@blackwellkrb yes, it's the same when dealing with exterior insulation, it needs to be in the right proportion to the internal insulation. I think flash and batt isn't that great, sure it's about cost, but with enough closed cell foam you easily get enough R value and it's over all simple and not causing you to deal with the worries of condensate accumulating in the fiberglass over time...
@@rthoeny7 if we figure 70F and 50rh, dewpoint is about 51F. Need enough insulation to keep the interior face of the sprayfoam above that temp or condensation will occur. Of course this will change with different indoor conditions but we humans like conditions around those numbers.
Do not use faced fiberglass. You are creating another vapor barrier trapping the moisture that the lack is spray foam created. Use unfaced fiberglass. Spray foam is a vabor barrier.