We have cathedral ceilings and after several years of water damage due to ice damming we changed to a steel roof. When doing the initial repairs, we discovered that the roof was barely vented at all which explained the ice damming. We added a 2x4 roof over the existing roof and we cut a 6" strip in the roof sheathing above the existing soffits to allow air flow into the new roof section. The style of roof allowed for ridge venting so that's what we went with. It's been 10 years now and we've had no issues. Significantly less ice buildup.
I'm a roofing contractor out of Canada and we had a very similar situation with a customer. He was having lots of condensation and ice damming. Every spring during the big snow melt it would leak in the building. Found out that the cathedral attic had spray foam right to the roof. We tore off the existing tin and put 2x4's vertically to create an air space. Than strapping on top of that. We installed a 33% vented soffit and then ridge venting and it hasn't leaked since.
@@bengary6558 Were in Canada as well and that sounds exactly the same as our fix. Venting a roof is the key, not only to minimizing water damage from ice damming but to longevity as well if you have a shingled roof. But I suppose, you already knew that. Cheers.
Purchased a house that was built in 1880. I am sure it has been updated over the years. Purchased it once before a remodel and had no issues with moisture in the attic and there were no signs of any previous moisture. House was completely gutted down to the studs and exterior walls and redone. I purchased the house for a second time after the remodel. I noticed moisture build up on the interior of the metal roof. The roof was older, expected to be about 20 years old or so at the time, basically new for the roof. There were 3 chimneys in the roof, one was cut off before the roof was installed and only 2 remained. When the house was remodeled all the brick was removed and one chimney was converted to be used as the vent for the oil furnace. There are 3 windows in the attic,2 were replaced with new and one was not due to its location behind the chimney. It was not accessible. After being in the house a couple years I noticed mold in the attic. I had it checked and was told to open the windows so the attic could vent. I told them I had tried it and it sweat more with the windows open then when they was closed. I have tried putting a contractor exhaust fan in an open window in attempt to suck out the moist air, it did not work. It only sweats in the winter months. I have yet to find a contractor who can come up with a solution. It did not start until after the house was gutted and everything replaced. Had the same issue with a place I rented before moving here. It was just a rental and so I let the landlord deal with it. But had the same issue, the roof sweat more with the attic window open.
Hi! Im thinking your problem may be related to combination of improper attic insulation and roof ventilation. Condensation occurs when there are large differences in temperature between the two areas, so I can only assume your attic is too warm from below in comparison to the outside cold air coming down through the metal roof and there is improper airflow to vent out the heat despite your opened window and running fan. The warm air is somehow trapped within the attic and not able to move outward properly. Another possibility is perhaps not enough insulation between your ceiling and the attic causing excessive heat going into the attic from rooms below, along with problem of improper attic ventilation. If you do a search on proper roof ventilation, you will see there are requirements related to the ratio of number of soffit vents to roof vents in order for a proper airflow outward. Otherwise, having roof vents without the needed soffit vents in properly spaced out locations around your parameter may still leave you out of the needed airflow to vent out heat buildup in attic. Therefore, although you may have your attic windows open, somehow the air movement may still not be flowing outward adequately and is perhaps even backdrafting and is holding in the warm air, causing even more condensation. This won't be a fix, but just a start, is try to open windows that are on on opposite walls to create a draft effect, preferably have fan blow inward from window(s) located on north side of house, and another fan on the south side window if any, but blow this one outward. The draft effect can help move more air in and out. If the windows are located west and east directions, then blow inward from west window and outward on east window. This works with how nature operates that the cold air in winter blows in from northwest direction so you're not fighting against nature's wind directions. Have roofers come out to assess whether you needed roof insulation, or is it more attic insulation between your joists. I suspect somehow excessive heat maybe going into your attic from down below. And metal roof is less insulated than asphalt shingles, so more cold air from above comes down to meet the hot air below forming higher than normal condensation. Good luck and hope you'd be able to figure all this out soon!
Oh, one other possibility is that the converted chimney may have inadvertantly created a draft flow pattern that somehow maybe keeping the hot air inside your attic as opposed to venting out.
Can you use baffles, then mineral wool from Rockville then R max ridge foam then gypsum rock. On a cathedral ceiling. Where building a new home. In Arizona at 4500 elevation with a 4:12 pitch roof. Should we put eave vents, soffit vents and ridge vents. Judy
I bought home with a metal roof on 2x4 perlins staggered 16". I am wondering if the rib channel on the metal can be counted as part of my air gap going to the ridge vent ?
Nice presentation! One thing I can say, I’ve used a lot of double bubble foil insulation on the roofing deck. It helps to keep the roof deck cool by reflecting heat in both directions, and I’ve seen this cure ice dam problems as well as it’s insulation and vapor barrier if installed properly.
I just ordered a metal building and paid for the double bubble , but then I seen a few videos of people who have the double bubble deteriorating and falling down .. so now I'm worried what I should do to not have the same happen
I had a metal roof put on a new house this past year and the installer didn't use any underlayment beneath the steel. Will I experience trouble in the future? We have a mix of scissor trusses on one part of the house, and vaulted ceilings on other parts, and so we insulated with spray foam beneath the rafters, end gables, and rim joists. TIA.
We are in sw Florida’s and had entegra concrete single roof damage from Hurricane Ian. We are trying to see if we need a new roof and planning on standing seam metal. What profile and connection type is the most hurricane resistant . And the Least Prone to further issues such as installer error. Since your roof is only as good as your installation.
Hi good to hear true professionals at work. With metal buildings such as light grade steel how would you eliminate thermal bridging as traditional screws where used causes it..? Is it possible to construct a passive house with LGS.?
Can you please let me know how I can stop condensation in my 36/24 metal garage i used the r-tech 2 inch insulation on all the walls and roof. I live in Washington state it rains here a lot I keep my boat and truck in it I put one of those electric wall heaters to keep it a little warm in there so some stuff doesn’t freeze in the winter we get freezing days and then we get day like spring and then condensation accumulate all over my boat truck every thing. Thanks for your help
Just got an insulated aluminium roof installed, there is a lot of condensation on the joints. The company that installed it just ran out of town. What can I do to remedy this?
Hello! I have a gazebo with a metal roof, and I want to put a wooden ceiling underneath. The problem is that in the morning condensation forms under the sheet metal. Will installing glass wool or styrofoam between the sheet metal roof and the wood ceiling fix the problem?
on an exposed fastener metal roof, I plan to install a high temp ice and water shield over the entire roof plywood decking. Then install 2x4 purlins horizontally. The closures at the bottom are foam while at the ridge vent are vented. What kind of closures at the eaves/drip edge allow air flow between the IWS and the ridge ? It appears the industry standard is to put a non vented foam strip between the metal roof and the drip edge at the eaves. How does air flow from the eaves to the ridge if foam closures don't allow it to flow? I am concerned with condensation forming on the underside of the metal roof and possible rot to the purlins.
Can you share how you'd recommend redoing the insulation in a metal walled travel trailer in order to prevent condensation within the walls for full-time living? Mine right now only have damaged fiberglass insulation in them.
Is condensation going to be an issue with new Standing seam roof going on over Ice and shield in a no attic house? I have low pitch less than 1"/12". Space above my ceilings is about a foot filled with spray foam insulation. Do I need a way to have space vented or I'm good with this very high R value newish house when new metal roof goes on? My builder says I don't need ventilation because of all the spray foam in the space. HELP
I'm putting a roof on my Timber Frame in April. Just ordered the metal package. Vaulted ceiling. I have a couple of questions. Looking at the codes in my area they are saying R-38---R-60 for the roof. This will require 12" of foam board insulation (giving me R-42). I'm going to have to build up the edges and furring strips with 2"x12"'s. The metal roof is corrugated. Will the corrugation provide enough ventilation or should I put additional venting say between the furring strips? Second question is should a vapor barrier be put down over the 2'x6" sub-roof or is tar paper enough? Thanks so much. I've been working on this Timber Frame for three years.
I have a 1800 square foot Quonset hut with no vents at all nor insulation and when it snows I get a lot of condensation inside even though the inside is not heated. Trying to figure out how to prevent that moisture. Considering a spray on foam throughout either inside/outside or both. Thoughts?
That has been done before, both to heat water and also to run heated water / glycol and prevent winter ice dams. Generally speaking, you will need to still support around the tubing with lumber.
I'm designing a passive house that uses metal SIPs as the structural roof, which will be sealed as much as humanly possible to the exterior of my ICF walls. The standing seam metal roof will stand-off the structural metal SIPs roof by way of perforated metal channels. The metal roof will have a mesh opening at the bottom and a ridge vent, but none of that ventilation will be common to the home, it's simply there to ventilate the under side of the metal roof. All of the moisture control within the home will be handled via HRV and a central dehumidifier. In short, the house will be sealed to an insane level (like a styrofoam cooler). The moisture, temperature, and air quality within the home will be monitored and managed via systems. The home will be efficient beyond the passive house standard, which greatly reduces the heating and cooling load, however some energy will be expended by the ventilation and dehumidification systems. I'll then have enough solar power to make the home capable of being off-the-grid, meaning net-zero. All that to say, the moisture will be managed within the home in a very controlled way.
nobody mentioned attic power fans, are they safe? Our home is over 100 years old and we had a serious "attic rain" incident, so we increased the amount of flow in the attic space and added a power vent that we have set to parameters for moisture or heat, then it just monitors the humidity and temp in the attic and turns itself on, fully replacing the air in the entire space in under 3 mins. Is this sustainable? We have not had a repeat since installing it, The only episode we had the weather went from -44c to 4 above in one day, and bam! It was raining inside my house! I was collecting ice cream pails full. Several neighbours were in the same mess. Would you say we have mitigated the problem or do we still need to add more ventilation?
I have an open lean to shed with the metal roof and I noticed ice crystals formed on the underside of the roof.. when the sun comes out all this ice turns into a rainstorm inside the shed.. it's not a question of heat. I considered putting up bubble wrap but then assumed I'd have bags of water hanging over my head. Is there any way to fix this?
Just had a metal roof installed. They did not put down plywood between metal and strapping. They left the old peel and stick in place as well before installing the new peel and stick. Its been about 2 weeks since completion and I was inspecting it and noticed a lot of condensation inside. Is closed cell spray foam insulation an option between strapping and metal to avoid problems? I'm not confident they did enough venting in the space.
i have a 12x16 gable barn with only vents at each end of building, my 2x 4 trusses sit on my 6' walls ,i what to put in insulation and ceiling . what will help with condensation
This is an interesting video topic. I have a family member who spent lots of money designing/building a quality made open carport . Built with high quality heavy wood beams. Open air concept. No attic. Wood underlayment, metal finished roof. Condensation every day under metal, with OPEN air concept. Needless to say the wood structure is not going to be around long without a lot if maintenance.
Just built this👇 This seam to work. I left a gap between the osb sheeting and the ssr. Made sure of adequate airflow from eave to the ridge c/w front and back 2” inserts on gable ends. Of course regular attic vents too.
I'm building a cold formed all metal building and want to insure that the insulation supplied with the kit doesn't get soaked from the "sweating". Is there a product I can Install that would give me a vapor barrier before I install the sheeting? Vendor told me that there's a vapor barrier in the insulation but it appears to be the white paper with the foil against the insulation. Seems backwards. Can you recommend a product?
I had a metal roof put on 3 years ago on my CB house. I moved somewhere else for 3 years. I am moving back in now and have condensation running down by cathedral ceilings. Paint is peeling off the ceiling. I live in south Florida so not cold but always humid. Oh, and my roofer retired. They used polystick and I think they covered the roof ridge. What is a low cost remedy?
Hey, we are having mold and sweaty vent issues really bad. We have a metal roof also. Could you please tell me who could come and look at our house to see what is causing the condensation and mold. We want to fix the problem not just clean it. Please we are having health problems that we are pretty sure related to the mold.Thank you! We live in MS.🙂🏡🏠🏡🏠
Just finished putting ice and water shield down over some v- groove pine for my timber frame pavilion, unheated space, will it be ok with the metal roofing applied directly to the ice and water shield?
I have a open porch with a metal roof. Some mornings it will feel like I'm getting rained on. Condensed water is on the underside of the metal roof. There is no drive of moisture from inside to outside since both sides of the metal roof are outside. Your discussion says nothing about this. Does this happen on all uninsulated metal roofs? Is this a radiational cooling issue?
Back in the 70's, I built a home and in an effort to be more energy efficient, I put .06 mil visqueen on the interior walls and ceilings. It caused a condensation plane at the back of the drywall, unfortunately! If you're going to do that, you must put a dehumidifier (whole house) in to remove the moisture in the house.
I was looking for a comment like this 💯🙏🏾 definitely a dehumidifier is what we all need in changer climates... gets the moisture out of the air.... we have 2 in our house and I can't believe the amount of water they catches 😳
I'm surprised you did not mention gable vents. I have gable vents at each end of my (40' length) house. I have installed a gable fan (south end) BUT do not have it hooked up electrically yet. It has a thermostat which is set at 110 F degrees....it's supposed to turn on automatically when the temp reaches 110 in the attic. Is this gable fan more for cooling off the attic in the summer. Does it help with moisture/condensation?? Should I be concerned with more condensation forming in the winter or summer??
I think this channel could do a lot better if they could add illustrations to complement their discussion. For instance, diagrams of the roof structure showing decking, rafters, insulation, vapor/moisture/radiant barriers, battens, air gaps, etc. I always have to go to other channels to get a more thorough explanation.
What if you put Styrofoam boards between the boards that you screw the metal roof onto? It will give you some insulation. Would that help or hurt condensation? I'm thinking about getting a metal roof right now and was thinking about buying some Styrofoam boards to do that. I'm in the South so it definitely gets extra hot.
My entire home is vaulted ceiling, and I'm thinking of putting a mechanical lock metal roof on it, as we have a shallow pitch. The more of these videos that I watch, the more issues I'm finding with my home! Since the low pitch necessitates an ice and water barrier (Colorado), I'm sure to have condensation issues without adding ventilation. One more thing to add to the list...
we live in northern mn and have cathedral ceilings ..... can you do a purlin over deck installation to get that air gap between your roof decking an the metal?
After inspecting various PBR style metal roofing systems. Im noticing rusting on the horizontal overlaps. Any ideas why this might be happening? The roofs are usually about 1/2 to 1/12 pitch.
Every situation tends to be unique but as a general rule, closed cell is usually the safest way to go. Email me at todd@asktoddmiller.com if you'd like to discuss your specific situation in detail.
I recently had a barn loft style building built by a business near me & they sol me some kind of barrier between my metal roofing & the interior called "technishield" or I think that's what they called it, its silver to look up from the inside. Does this matter work well for condensation or did I pay extra for something that really on stops rattling?
I have a 40 x 14 all metal RV /carport. I get a lot of dripping from the underside when it hits the dew point. Would you think one inch of closed cell spray foam underneath would be a good idea for a thermal break? Thanks
Yes, the 1" closed cell (or open cell) foam sprayed directly onto the underside of the metal roof would be a great idea to reduce/prevent the underside surface of the metal roof from reaching the dew point. Condensation will continue to form on the top side of the metal roof, but that is not a problem that needs a solution. The condensation problem (on the underside) arises from the top side of the metal roof facing the night sky. The night sky (especially on clear nights) causes the surface temperature of the metal roof to become much colder than the ambient air temperature because the temperature of deep space is hundreds of degrees below zero. The severity of the condensation increases with flat roofs vs. pitched roof surfaces. You are probably aware that the degree of condensation isn't as severe on cloudy or partly cloudy nights. Because physics dictates that more moves to less to become equal. The top side of the cold metal roof causes the underside of the metal roof to become cold enough to reach the dew point because of heat transfer (conduction). The dew point is the temperature at which water in vapor form condenses into liquid water droplets. Depending on the outdoor relative humidity (rh), there is a very good likelihood that condensation is also forming on the top side of the metal roof (as mentioned earlier). An example of surfaces facing the night sky is morning dew on the grass, but not on the grass under the leaves of trees due to the fact that grass under the 'shade" of the trees does not "see" the night sky. Another common example is car surfaces that face the night sky (I.e., hoods, tops, etc.) incur more condensation than the vertical surfaces (door panels, door windows). In northern climates, river water under bridges is the last to freeze because the water under the bridge does not "see" the night sky. Eventually, the below freezing air temperatures do freeze the water under the bridges. Going back to metal roofs, when you think about it, it's really simple physics, but I never see this explanation from metal roof "experts." Another (expensive) way to solve the metal roof condensation issue is to build a vented over-roof to prevent the metal roof from being exposed the the night sky. Vented over-roofs are often a reliable solution for condensation issues, but the explanation as to why they solve condensation issues is never revealed, thus the science (physics) isn't spread to those people who could make this information common knowledge. Vented over-roofs in northern climates are a reliable solution for eliminating ice dams providing the venting doesn't become blocked.
Hi. I've been watching some of your videos, and have a serious question for you. I have installed shingles, metal roofs quite few times, but recently, I've found myself in a dilemma. I recently bought a manufactured home, single-wide 16' x 80'. I replaced the original gutters with 5" k-style aluminum house gutters. Although it has no leaks, I want to do some preventative maintenance to insure against potential future leaks. This home has a slightly-pitched gable style, "loose roof" in that it is attached with staples at edges. My dilemma; should I use a 100% silicone roof coating such as Henry's, or metal roofing? I have a friend that is a professional roofer that suggests completely covering my entire roof with peel & stick, ice &water shield, then stripping (furring) it out, and installing the roofing metal. I'm very concerned about condensation using either method. The roof has no eaves therefore no soffits for vents. I'm concerned about my existing roof developing condensation problems, wetting my insulation, mold, mildew. Can I get you opinion on this please?
What is the difference between the standard metal roofing with exposed fasteners that i see on many buildings, and standing-seam metal roofing that seems to be more expensive?
Standing seam metal roofing has hidden fasteners which aren't in contact with the elements like exposed fastener metal roofing. To learn more, check out this video: bit.ly/exposed-fastener-vs-standing-seam-revisited-video -Thad
great ... 1) what if the humidity outside is greater than your A/C'd climate controlled interior where the outside humidity wants to get inside the house ??? 2) Even an open metal building gets water dripping from the underside of the rook panels ...
I live in a manufactured home with a low pitched gable type metal roof. This roof is referred to as "loose roof" in that it is just attached by staples around the edges, everything in between sort of floating. I have no leaks, have just installed 5" K style house shingles. My question; to future-proof the roof, would you suggest covering entire roof with peel & stick, ice & water shield, then screw my wooden lat strips (1"x4" or 1"x6""), which I'll crosscut 1/4" every foot on the peel & stick contact side, through the existing metal roof and peel & stick to existing rafters, horizontally at aprox 2' OC, then install 29 gauge metal roofing? Or roll my existing roof with Henry's 100% white silicone, high reflectivity roof coating with limited lifetime warranty? The comment was made about covering en entire roof with ice & water shield creating condensation, so now I'm wondering which would be best. Please bear in mind the fact I live in Alabama where summer temps can, and do, regularly reach triple digits. Your advice will certainly be appreciated
I n the USA the roofs of houses have ply wood & shingles but other countries they use clay roof tiles for houses which are cheaper to maintain than sheetmetal roofs , for example transportation, replacement of full sheets is becoming too expensive than individual clay tiles being replaced.
As can be seen by the numerous questions asked and unanswered, videos like these provide a content the author gets paid for by the number of times they are watched, but the author doesn't care about their audience or their input. They only post and forget for the money.
I have a open carport with no walls or gables. It's raining underneath in cold weather. You said right just make some lemonade , then figure out how to make it out of wood....
The condensation problem (on the underside) arises from the top side of the metal roof facing the night sky. The night sky (especially on clear nights) causes the surface temperature of the metal roof to become much colder than the ambient air temperature because the temperature of black deep space is hundreds of degrees below zero. The severity of the condensation increases with flat roofs vs. pitched roof surfaces. Please be aware that the degree of condensation isn't as severe on cloudy or partly cloudy nights. Simply stated, physics dictates that more moves to less to become equal. The top side of the cold metal roof causes the underside of the metal roof to become cold enough to reach the dew point because of heat transfer (conduction). The dew point is the temperature at which water in vapor form condenses into liquid water droplets. Depending on the outdoor relative humidity (rh), there is a very good likelihood that condensation is also forming on the top side of the metal roof (not a problem). An example of surfaces facing the night sky is morning dew on the grass, but not on the grass under the leaves of trees due to the fact that grass under the 'shade" of the trees does not "see" the night sky. Another common example is car surfaces that face the night sky (i.e., hoods, tops, etc.) incur more condensation than the vertical surfaces (i.e., door panels, door windows). In northern climates, river water under bridges is the last to freeze because the water under the bridge does not "see" the night sky. Eventually, the continuous below freezing air temperatures do freeze the water under the bridges. Going back to metal roofs, when you think about it, it's really simple physics, but I never see this explanation from metal roof "experts." Why is that?
Our house house has a corrugated tin roof on the back addition. No installation on the roof and it's loud can we install installation a vapor barrier and drywall on it? To make a ceiling?
I'm building a new home with ICF walls from footing to top of wall and from everything I've heard and been told this is more or less an airtight system. I plan on installing vaulted trusses 5/12 outer and 3/12 inner with 5/8" decking and all the sealing products then a breathable underlay beneath the steel and to my thinking is that with a vent ridge cap that would vent the roof no matter which way the wind blows. Inside I plan to spray on a 2-3" closed cell foam to address air leakage and moisture issues. Since it is a new home it will need a good air ex changer anyway and one could then vent into the 'attic' and draw/control any moisture that gets into the space and not have to worry about venting already heated or cooled air to the outside. It is in a dry zone in the lower portion of Alberta Canada and humidity is really not an issue.
Would there be any condensation issues in a semi-conditioned attics (w/ open cell spray foam insulation on underside of roof deck) - also in the Alabama? Architect is saying no ice and water shield and no gap b/t standing seam roof and deck necessary - only a synthetic underlayment. How do you recommend installs with spray foamed roof decks / attics?
To many factors in the south lol we get all 4 seasons in a week. I can’t find a good answer either about spray foam and metal roof. I hear roof rot and wet roofs . Then I hear spray foam is best thing ever. But can’t find any real science for that combo in the south.
@@JS-zb1vv That is exactly where I am at right now. I am building a house and they did Galva loom metal roof directly on top of the 2 x 4 strippers on the rafters. I was considering spray foam but it seems like it it is almost still like the Covid vaccine everybody has a different opinion. Did you ever make a decision? I am meeting with a spray foam guy right now to see what he has to say
@@mxermatt1 I just put spray foam in my parents house. Closed cell in walls and open cell in attic. They have a metal roof. Only had it for 2 years so far . Probably to early to tell. But it is very very easy to heat and cool . I will absolutely make sure the window seals are protected well. Because the windows will condensate. I hope it was the right choice. Good luck because I talked to 3 foam guys and all were different. But there isn’t any real science with this . Even these guys making videos won’t answer these questions.
This is what I want to know: I am rebuilding part of my barn. I am just stretching 9 foot long 2x6s over a span and putting metal roofing on the top of these spaces out 2x6's. My question is if I should put plywood over those 2x6's in between them and the metal roofing? I really want to keep the weight down.
Another (expensive) way to solve the metal roof condensation issue is to build a vented over-roof to prevent the metal roof from being exposed the night sky. Vented over-roofs are often a reliable solution for condensation issues, but the explanation as to why they solve condensation issues is never revealed, thus the science (physics) isn't spread to those people who could make this information common knowledge. Vented over-roofs in northern climates are a reliable solution for eliminating ice dams providing the venting doesn't become blocked.
What are your thoughts on steel roofing panels installed over strapping on rafters - no plywood/or underlayment? On a channel I've enjoyed watching, they've constructed a post & Beam home....love the basic design, but thought the roof was way to risky on the condensation front: (Current Moisture issue: ruclips.net/video/C2LveKCyRuk/видео.html, install of steel roof: ruclips.net/video/ByE7JgZHK-E/видео.html). It seems that he did a great job separating the in-home sources of condensation from the attic space, however my concern is frost/and external sources of condensation. Please speak about your thoughts on this issue. I'm a steel roofer, and personally always recommend underlayment on plywood for new construction with a home.
I am finishing a bare bones attic and noticed a little moisture on the insulation. I pulled a piece down there was a piece of foam in between the rafters, pulled that down and I was shocked to see the metal roof. By the end of the day there was about 20 leaking spots that were visable. I'm from Pennsylvania and never heard of a roof done this was. If anyone sees this and has any tips or tricks to help rectify this problem it would be greatly appreciated
@@dippy-egg The entire under-steel-roof-condensation issue is related to "moist air flow", and cold steel. Just as when you take a "cold glass" of something out of the fidge, it quickly forms condensation, the same principle is true of a steel roof. In the evening your roof gets cold (or sometimes the day if you are in a cold climate). There are two basic ways roof systems are designed: Vaulted ceilings underneath (insulation with no air flow), or "cold air under", roofs. the "cold air under roofs" is the most common, and rely on venting at the eaves which permits "cold air" to enter, and upper venting to allow the "warmed air" to escape. The principle of "cold air under roofs", is to keep both sides of the roof material at cool temperature: for shingles, this helps to cool the shingles and make them last longer, and for steel, it is supposed to ensure that the temperature on the upper surface and lower surface are similar... and hopefully are not hovering around the condensation temperature range. In practice however: all "cold roofs" eventually hover around the "condensation point", and thus condensation will form in some conditions. The idea behind interior home "vapor barrier" is limiting the flow of "moist air" past a "cold surface". The problem with this kind of flow, is that as the moist air passes the cold surface it will essentially "rain condensation" on to the cold surface. This is how de-humdifyers work: they make a cold "coil" of copper pipe by pumping a refrigerant through it, and blow the "moist air" past the cold surface. The moisture condenses and drips' off. So basically what I'm saying is: It almost sounds like, by removing the foam" you described, you introduced a flow path for "moist air" to pass by the cold steel roof. Underlayment should have been installed under the steel roof. However some folks don't do this to save money. I personally don't recommend this installation method and would recommend installing underlayment. However, that can be expensive. It is basically 2x the cost of installing a roof: and potentially more if the installer elected to use seams between the installed steel (if they sealed/caulked the seams then removal would likely result in destruction of the steel panels). If you recently opened up an "attic hole" under your roof, then you likely introduced a big opening and path for "moist air" to travel under your roof and condense under your roof. If this is the case, this opening should be closed regularly, and only opened for access. The air that travels under your roof should come from outside (cold/dry), and flow up/out the vents (in and up rafter vents, and out the peak vents or gable end vents). If you have a leaky ceiling that permits "cold moist air" from your living space to flow into the under-roof space, these holes should be stopped/sealed. If this isn't' the case, you could add a forced-air vent fan in the attic to improve cold air flowing from the underside of the roof..... Another potential problem that you could have created is the access of cold outside air from flowing in and under your attic space. Air flow paths should open from the eave of your roof up into the attic space. "Moore vents" are typically used for this. a Moore vent can be either "foam"/ cardboard, or even created with wood (see here: www.energystar.gov/campaign/seal_insulate/do_it_yourself_guide/adding_attic_insulation/installing_rafter_vents) . If this is the the "foam" that you are referring to, then your removal of them would basically permit the insulation at the eave to stop air flow, and then you would have created your own problem... Not sure if this helps...but with no pictures of what your issue is...I'm kind of just guessing>>> Cheers Graham From WheelerSteel.ca
Was that Thads casting couch from his other channel... 😆jk just trying to keep it light. Good meat and potatoes metal roofing video as usual! Thanks Thad!
So essentially roof, siding and living space all have their own venting systems. The moment you introduce moisture from one to the other it’s a potential problem. Does the radiant barrier help with drying out condensation and what are the chances of dust reducing its radient efficiency?
Consider the use of ridged foam sheet insulation. If it’s installed properly & is thick enough, water vapor will not condense & cannot pass through. I like polyisocyanurate .
@@ryanspence7239 I used ice and water shield 3/4 of the way up my 9-12 pitch roof and then warrior #30 felt roof paper the last 1/4 of the roof. I was told not to go to the top of the roof with the ice and water shield because it won't let the house breathe and cause condensation. I also will have cathedral ceilings so the only venting will be out through the ridge.
You showed no layers. After each example discussed, you should have shown us a stick fire sample or diagram, something...otherwise it's a could be word salad that we are trying to imagine such as the wrong time to use ice and water shield sounds just like when you should. A reason the inspector has to be able to see the layers,nit just as proof, and not just told an R-value as described. Thanks
Lots of good advice here. Ice and water shield is OK for the lower 4 feet of the roof. Covering the whole roof is a mistake. If you have an interior vapour barrier or foamed roof, you have just created a plastic mold sandwich. Tar paper works well, is time proven, and cheap!
I think you are making incorrect statements. People should NOT be using polyethylene plastic in walls or ceilings. There are other products that should be used when facings are required to control vapor migration. There are engineered products like Intello or even Kraft paper. Secondly, ice and water shield is supposed to be used only at the eves and valleys preventing ice dam damage and possibly around skylights whereas synthetic underlayment should be predominantly used. Focus on air barrier to prevent air moving into the home.
"LET'S FACE IT: A LOT OF BUILDING MATERIALS THAT WE USE DON'T BREATH A GREAT DEAL" OH DAMN. YOU CONFRONTED IT HEAD ON. I HAVE BEEN LYING TO MYSELF FOR YEARS ABOUT THIS, AND THEN YOU GO SPEAK THE TRUTH IN THE PUBLIC LIKE THAT. I FEEL SO VULNERABLE. SOMEBODY HOLD ME. THIS GUY DOESN'T HOLD ANYTHING BACK. WATCH OUT!!! HE'S A WILD ONE. TRUTH TO POWER. EPIC HERO. FOR BIDEN'S SAKE, IT SURE IS GOOD HE ISN'T IN GOVERNMENT, BECAUSE HE WOULDN'T LAST LONG!!!!
@@TheMetalRoofingChannel There's a lot of sibilance or harshness. If you're not hearing it you may look into getting a new amp, speakers or headphones. (Or someone with their hearing intact...) Putting the mic on a stand and putting some acoustic foam/matting down on the table may help.
I've checked this out in multiple listening environments and rooms i.e. headphones, studio monitors, laptop speakers. I might have had the exciter set a bit high in my mastering chain and probably could've pulled down the 10k range with the EQ/used a de-esser. You can see on the right side of the screen I am running multiple microphones, so the recorder itself is only providing partial audio anyways. If it sounds harsh with your setup it's more likely a post processing issue rather than a mic issue. I'll look into that for future episodes as well. -Thad
@@TheMetalRoofingChannel Make sure the microphones on the recorder are actually turning themselves off when you plug an external in. See "The Tascam DR-05 audio recorder is a horrible device" by louis rossmann.
@@TheMetalRoofingChannel why didn’t you show cross sections of ventilations for different styles of problems. Plan drawings of ventilations styles for all the types of problems that occur would have been better than talking about the problem. Being almost a Jr Architect and was on my way to being a AIA Architect, I stopped and went to a different career path. Drawings/pictures or diagrams to that show the fixes or the problems to show a clientele helps better their understanding not your ability to talk about it.
@@urf808 Noted, drawings would have been good to show in this video. Some of our recent videos incorporate those type of graphics more readily. Always looking to improve! -Thad
A Whole Bunch Of TALK, With NO Pictorial Examples Of What They Are Talking About. NOT Very Interesting. This Video Must Be Made For Metal Roofers, Already Dealing With Instillation Concerns.
Hi. I've been watching some of your videos, and have a serious question for you. I have installed shingles, metal roofs quite few times, but recently, I've found myself in a dilemma. I recently bought a manufactured home, single-wide 16' x 80'. I replaced the original gutters with 5" k-style aluminum house gutters. Although it has no leaks, I want to do some preventative maintenance to insure against potential future leaks. This home has a slightly-pitched gable style, "loose roof" in that it is attached with staples at edges. My dilemma; should I use a 100% silicone roof coating such as Henry's, or metal roofing? I have a friend that is a professional roofer that suggests completely covering my entire roof with peel & stick, ice &water shield, then stripping (furring) it out, and installing the roofing metal. I'm very concerned about condensation using either method. The roof has no eaves therefore no soffits for vents. I'm concerned about my existing roof developing condensation problems, wetting my insulation, mold, mildew. Can I get you opinion on this please?
Where is the home? Big difference in the answer. I'm in New York and after fixing my gutters and having them ripped off again for years, finally decided to take them off before winter. I might put them back up in the spring, I dunno.
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We have cathedral ceilings and after several years of water damage due to ice damming we changed to a steel roof. When doing the initial repairs, we discovered that the roof was barely vented at all which explained the ice damming. We added a 2x4 roof over the existing roof and we cut a 6" strip in the roof sheathing above the existing soffits to allow air flow into the new roof section. The style of roof allowed for ridge venting so that's what we went with. It's been 10 years now and we've had no issues. Significantly less ice buildup.
I'm a roofing contractor out of Canada and we had a very similar situation with a customer. He was having lots of condensation and ice damming. Every spring during the big snow melt it would leak in the building. Found out that the cathedral attic had spray foam right to the roof. We tore off the existing tin and put 2x4's vertically to create an air space. Than strapping on top of that. We installed a 33% vented soffit and then ridge venting and it hasn't leaked since.
@@bengary6558 Were in Canada as well and that sounds exactly the same as our fix. Venting a roof is the key, not only to minimizing water damage from ice damming but to longevity as well if you have a shingled roof. But I suppose, you already knew that. Cheers.
Great to hear experts that are on top of their game.
Purchased a house that was built in 1880. I am sure it has been updated over the years. Purchased it once before a remodel and had no issues with moisture in the attic and there were no signs of any previous moisture. House was completely gutted down to the studs and exterior walls and redone. I purchased the house for a second time after the remodel. I noticed moisture build up on the interior of the metal roof. The roof was older, expected to be about 20 years old or so at the time, basically new for the roof. There were 3 chimneys in the roof, one was cut off before the roof was installed and only 2 remained. When the house was remodeled all the brick was removed and one chimney was converted to be used as the vent for the oil furnace. There are 3 windows in the attic,2 were replaced with new and one was not due to its location behind the chimney. It was not accessible. After being in the house a couple years I noticed mold in the attic. I had it checked and was told to open the windows so the attic could vent. I told them I had tried it and it sweat more with the windows open then when they was closed. I have tried putting a contractor exhaust fan in an open window in attempt to suck out the moist air, it did not work. It only sweats in the winter months. I have yet to find a contractor who can come up with a solution. It did not start until after the house was gutted and everything replaced. Had the same issue with a place I rented before moving here. It was just a rental and so I let the landlord deal with it. But had the same issue, the roof sweat more with the attic window open.
Hi! Im thinking your problem may be related to combination of improper attic insulation and roof ventilation. Condensation occurs when there are large differences in temperature between the two areas, so I can only assume your attic is too warm from below in comparison to the outside cold air coming down through the metal roof and there is improper airflow to vent out the heat despite your opened window and running fan. The warm air is somehow trapped within the attic and not able to move outward properly.
Another possibility is perhaps not enough insulation between your ceiling and the attic causing excessive heat going into the attic from rooms below, along with problem of improper attic ventilation.
If you do a search on proper roof ventilation, you will see there are requirements related to the ratio of number of soffit vents to roof vents in order for a proper airflow outward. Otherwise, having roof vents without the needed soffit vents in properly spaced out locations around your parameter may still leave you out of the needed airflow to vent out heat buildup in attic. Therefore, although you may have your attic windows open, somehow the air movement may still not be flowing outward adequately and is perhaps even backdrafting and is holding in the warm air, causing even more condensation.
This won't be a fix, but just a start, is try to open windows that are on on opposite walls to create a draft effect, preferably have fan blow inward from window(s) located on north side of house, and another fan on the south side window if any, but blow this one outward. The draft effect can help move more air in and out.
If the windows are located west and east directions, then blow inward from west window and outward on east window. This works with how nature operates that the cold air in winter blows in from northwest direction so you're not fighting against nature's wind directions.
Have roofers come out to assess whether you needed roof insulation, or is it more attic insulation between your joists. I suspect somehow excessive heat maybe going into your attic from down below. And metal roof is less insulated than asphalt shingles, so more cold air from above comes down to meet the hot air below forming higher than normal condensation.
Good luck and hope you'd be able to figure all this out soon!
Oh, one other possibility is that the converted chimney may have inadvertantly created a draft flow pattern that somehow maybe keeping the hot air inside your attic as opposed to venting out.
Can you use baffles, then mineral wool from Rockville then R max ridge foam then gypsum rock. On a cathedral ceiling. Where building a new home. In Arizona at 4500 elevation with a 4:12 pitch roof. Should we put eave vents, soffit vents and ridge vents. Judy
I bought home with a metal roof on 2x4 perlins staggered 16". I am wondering if the rib channel on the metal can be counted as part of my air gap going to the ridge vent ?
With a vaulted ceiling with a steel roof on it can you put a whirlybird on there where that help get rid of moisture
I have this 12x32 building with a metal roof, what are your suggestions to prevent moisture before insulating
Nice presentation! One thing I can say, I’ve used a lot of double bubble foil insulation on the roofing deck. It helps to keep the roof deck cool by reflecting heat in both directions, and I’ve seen this cure ice dam problems as well as it’s insulation and vapor barrier if installed properly.
I just ordered a metal building and paid for the double bubble , but then I seen a few videos of people who have the double bubble deteriorating and falling down .. so now I'm worried what I should do to not have the same happen
I had a metal roof put on a new house this past year and the installer didn't use any underlayment beneath the steel. Will I experience trouble in the future? We have a mix of scissor trusses on one part of the house, and vaulted ceilings on other parts, and so we insulated with spray foam beneath the rafters, end gables, and rim joists. TIA.
We are in sw Florida’s and had entegra concrete single roof damage from Hurricane Ian. We are trying to see if we need a new roof and planning on standing seam metal. What profile and connection type is the most hurricane resistant . And the
Least
Prone to further issues such as installer error. Since your roof is only as good as your installation.
Hi good to hear true professionals at work. With metal buildings such as light grade steel how would you eliminate thermal bridging as traditional screws where used causes it..? Is it possible to construct a passive house with LGS.?
Can you please let me know how I can stop condensation in my 36/24 metal garage i used the r-tech 2 inch insulation on all the walls and roof. I live in Washington state it rains here a lot I keep my boat and truck in it I put one of those electric wall heaters to keep it a little warm in there so some stuff doesn’t freeze in the winter we get freezing days and then we get day like spring and then condensation accumulate all over my boat truck every thing. Thanks for your help
Just got an insulated aluminium roof installed, there is a lot of condensation on the joints. The company that installed it just ran out of town. What can I do to remedy this?
What if you have an attic ceiling completely sealed via closed cell spray foam? Switching to a standard seam metal roof. Should I be worried?
Hello! I have a gazebo with a metal roof, and I want to put a wooden ceiling underneath. The problem is that in the morning condensation forms under the sheet metal. Will installing glass wool or styrofoam between the sheet metal roof and the wood ceiling fix the problem?
on an exposed fastener metal roof, I plan to install a high temp ice and water shield over the entire roof plywood decking. Then install 2x4 purlins horizontally. The closures at the bottom are foam while at the ridge vent are vented. What kind of closures at the eaves/drip edge allow air flow between the IWS and the ridge ? It appears the industry standard is to put a non vented foam strip between the metal roof and the drip edge at the eaves. How does air flow from the eaves to the ridge if foam closures don't allow it to flow? I am concerned with condensation forming on the underside of the metal roof and possible rot to the purlins.
Good question. I had the same question but I see no one has answered yet. have you found the answer through other sources? Thanks
Can you share how you'd recommend redoing the insulation in a metal walled travel trailer in order to prevent condensation within the walls for full-time living? Mine right now only have damaged fiberglass insulation in them.
Is condensation going to be an issue with new Standing seam roof going on over Ice and shield in a no attic house? I have low pitch less than 1"/12". Space above my ceilings is about a foot filled with spray foam insulation. Do I need a way to have space vented or I'm good with this very high R value newish house when new metal roof goes on? My builder says I don't need ventilation because of all the spray foam in the space. HELP
I'm putting a roof on my Timber Frame in April. Just ordered the metal package. Vaulted ceiling. I have a couple of questions. Looking at the codes in my area they are saying R-38---R-60 for the roof. This will require 12" of foam board insulation (giving me R-42). I'm going to have to build up the edges and furring strips with 2"x12"'s. The metal roof is corrugated. Will the corrugation provide enough ventilation or should I put additional venting say between the furring strips? Second question is should a vapor barrier be put down over the 2'x6" sub-roof or is tar paper enough? Thanks so much. I've been working on this Timber Frame for three years.
I have a 1800 square foot Quonset hut with no vents at all nor insulation and when it snows I get a lot of condensation inside even though the inside is not heated. Trying to figure out how to prevent that moisture. Considering a spray on foam throughout either inside/outside or both. Thoughts?
Is it possible to put plex tubes under the panels to heat water
That has been done before, both to heat water and also to run heated water / glycol and prevent winter ice dams. Generally speaking, you will need to still support around the tubing with lumber.
This is what we are doing to cycle the hot water to a pre hot water tank.
I'm designing a passive house that uses metal SIPs as the structural roof, which will be sealed as much as humanly possible to the exterior of my ICF walls. The standing seam metal roof will stand-off the structural metal SIPs roof by way of perforated metal channels. The metal roof will have a mesh opening at the bottom and a ridge vent, but none of that ventilation will be common to the home, it's simply there to ventilate the under side of the metal roof. All of the moisture control within the home will be handled via HRV and a central dehumidifier.
In short, the house will be sealed to an insane level (like a styrofoam cooler). The moisture, temperature, and air quality within the home will be monitored and managed via systems.
The home will be efficient beyond the passive house standard, which greatly reduces the heating and cooling load, however some energy will be expended by the ventilation and dehumidification systems. I'll then have enough solar power to make the home capable of being off-the-grid, meaning net-zero.
All that to say, the moisture will be managed within the home in a very controlled way.
Great idea …but not practical for most people both in complexity and affordability
nobody mentioned attic power fans, are they safe? Our home is over 100 years old and we had a serious "attic rain" incident, so we increased the amount of flow in the attic space and added a power vent that we have set to parameters for moisture or heat, then it just monitors the humidity and temp in the attic and turns itself on, fully replacing the air in the entire space in under 3 mins. Is this sustainable? We have not had a repeat since installing it, The only episode we had the weather went from -44c to 4 above in one day, and bam! It was raining inside my house! I was collecting ice cream pails full. Several neighbours were in the same mess. Would you say we have mitigated the problem or do we still need to add more ventilation?
I have an open lean to shed with the metal roof and I noticed ice crystals formed on the underside of the roof.. when the sun comes out all this ice turns into a rainstorm inside the shed.. it's not a question of heat. I considered putting up bubble wrap but then assumed I'd have bags of water hanging over my head. Is there any way to fix this?
You see a lot of metal sheeting roofing right on top of the purlins attached to the trusses with no vapor barrier at all.
Just had a metal roof installed. They did not put down plywood between metal and strapping. They left the old peel and stick in place as well before installing the new peel and stick. Its been about 2 weeks since completion and I was inspecting it and noticed a lot of condensation inside.
Is closed cell spray foam insulation an option between strapping and metal to avoid problems? I'm not confident they did enough venting in the space.
i have a 12x16 gable barn with only vents at each end of building, my 2x 4 trusses sit on my 6' walls ,i what to put in insulation and ceiling . what will help with condensation
This is an interesting video topic. I have a family member who spent lots of money designing/building a quality made open carport . Built with high quality heavy wood beams. Open air concept. No attic. Wood underlayment, metal finished roof. Condensation every day under metal, with OPEN air concept. Needless to say the wood structure is not going to be around long without a lot if maintenance.
Do you have any details on ways to prevent condensation is steel buildings using a standing seam roof?
Just built this👇
This seam to work. I left a gap between the osb sheeting and the ssr. Made sure of adequate airflow from eave to the ridge c/w front and back 2” inserts on gable ends.
Of course regular attic vents too.
I'm building a cold formed all metal building and want to insure that the insulation supplied with the kit doesn't get soaked from the "sweating". Is there a product I can Install that would give me a vapor barrier before I install the sheeting? Vendor told me that there's a vapor barrier in the insulation but it appears to be the white paper with the foil against the insulation. Seems backwards. Can you recommend a product?
I had a metal roof put on 3 years ago on my CB house. I moved somewhere else for 3 years. I am moving back in now and have condensation running down by cathedral ceilings. Paint is peeling off the ceiling. I live in south Florida so not cold but always humid. Oh, and my roofer retired. They used polystick and I think they covered the roof ridge. What is a low cost remedy?
Hey, we are having mold and sweaty vent issues really bad. We have a metal roof also. Could you please tell me who could come and look at our house to see what is causing the condensation and mold. We want to fix the problem not just clean it. Please we are having health problems that we are pretty sure related to the mold.Thank you! We live in MS.🙂🏡🏠🏡🏠
What is the white residue evident on the underside/dripping from the underside of the carport sheeting during or post the process of condensation?
Just finished putting ice and water shield down over some v- groove pine for my timber frame pavilion, unheated space, will it be ok with the metal roofing applied directly to the ice and water shield?
I have a open porch with a metal roof. Some mornings it will feel like I'm getting rained on. Condensed water is on the underside of the metal roof. There is no drive of moisture from inside to outside since both sides of the metal roof are outside. Your discussion says nothing about this. Does this happen on all uninsulated metal roofs? Is this a radiational cooling issue?
Back in the 70's, I built a home and in an effort to be more energy efficient, I put .06 mil visqueen on the interior walls and ceilings. It caused a condensation plane at the back of the drywall, unfortunately! If you're going to do that, you must put a dehumidifier (whole house) in to remove the moisture in the house.
I was looking for a comment like this 💯🙏🏾 definitely a dehumidifier is what we all need in changer climates... gets the moisture out of the air.... we have 2 in our house and I can't believe the amount of water they catches 😳
How many passive houses have vented attics (by %)?
Very good conversation and explanation.
Should metal roofing be installed on battens or right overtop of the decking? Nobody has a clear answer.
I'm surprised you did not mention gable vents. I have gable vents at each end of my (40' length) house. I have installed a gable fan (south end) BUT do not have it hooked up electrically yet. It has a thermostat which is set at 110 F degrees....it's supposed to turn on automatically when the temp reaches 110 in the attic. Is this gable fan more for cooling off the attic in the summer. Does it help with moisture/condensation?? Should I be concerned with more condensation forming in the winter or summer??
I think this channel could do a lot better if they could add illustrations to complement their discussion. For instance, diagrams of the roof structure showing decking, rafters, insulation, vapor/moisture/radiant barriers, battens, air gaps, etc. I always have to go to other channels to get a more thorough explanation.
Good thoughts, Mark. I'm always looking to improve the channel, and I'll work on getting more visuals incorporated! -Thad
What if you put Styrofoam boards between the boards that you screw the metal roof onto? It will give you some insulation. Would that help or hurt condensation? I'm thinking about getting a metal roof right now and was thinking about buying some Styrofoam boards to do that. I'm in the South so it definitely gets extra hot.
Great topic, thanks...
Can I use tar paper under my metal panels to prevent condensation inside my older trailer house??
My entire home is vaulted ceiling, and I'm thinking of putting a mechanical lock metal roof on it, as we have a shallow pitch. The more of these videos that I watch, the more issues I'm finding with my home! Since the low pitch necessitates an ice and water barrier (Colorado), I'm sure to have condensation issues without adding ventilation. One more thing to add to the list...
we live in northern mn and have cathedral ceilings ..... can you do a purlin over deck installation to get that air gap between your roof decking an the metal?
You should be more specific, because shallow is a bit ambiguous. Even then, different metal roof types have different minimum slope requirements.
You can also add exterior double insulation panels to the roof deck.
Power roof vent works great...
After inspecting various PBR style metal roofing systems. Im noticing rusting on the horizontal overlaps. Any ideas why this might be happening? The roofs are usually about 1/2 to 1/12 pitch.
Closed or open cell foam in trusses . Is it a problem for metal roofs ? Especially in the south
Every situation tends to be unique but as a general rule, closed cell is usually the safest way to go. Email me at todd@asktoddmiller.com if you'd like to discuss your specific situation in detail.
I recently had a barn loft style building built by a business near me & they sol me some kind of barrier between my metal roofing & the interior called "technishield" or I think that's what they called it, its silver to look up from the inside. Does this matter work well for condensation or did I pay extra for something that really on stops rattling?
I have a 40 x 14 all metal RV /carport. I get a lot of dripping from the underside when it hits the dew point. Would you think one inch of closed cell spray foam underneath would be a good idea for a thermal break? Thanks
Yes, the 1" closed cell (or open cell) foam sprayed directly onto the underside of the metal roof would be a great idea to reduce/prevent the underside surface of the metal roof from reaching the dew point. Condensation will continue to form on the top side of the metal roof, but that is not a problem that needs a solution.
The condensation problem (on the underside) arises from the top side of the metal roof facing the night sky. The night sky (especially on clear nights) causes the surface temperature of the metal roof to become much colder than the ambient air temperature because the temperature of deep space is hundreds of degrees below zero. The severity of the condensation increases with flat roofs vs. pitched roof surfaces. You are probably aware that the degree of condensation isn't as severe on cloudy or partly cloudy nights. Because physics dictates that more moves to less to become equal. The top side of the cold metal roof causes the underside of the metal roof to become cold enough to reach the dew point because of heat transfer (conduction). The dew point is the temperature at which water in vapor form condenses into liquid water droplets. Depending on the outdoor relative humidity (rh), there is a very good likelihood that condensation is also forming on the top side of the metal roof (as mentioned earlier). An example of surfaces facing the night sky is morning dew on the grass, but not on the grass under the leaves of trees due to the fact that grass under the 'shade" of the trees does not "see" the night sky. Another common example is car surfaces that face the night sky (I.e., hoods, tops, etc.) incur more condensation than the vertical surfaces (door panels, door windows). In northern climates, river water under bridges is the last to freeze because the water under the bridge does not "see" the night sky. Eventually, the below freezing air temperatures do freeze the water under the bridges. Going back to metal roofs, when you think about it, it's really simple physics, but I never see this explanation from metal roof "experts."
Another (expensive) way to solve the metal roof condensation issue is to build a vented over-roof to prevent the metal roof from being exposed the the night sky. Vented over-roofs are often a reliable solution for condensation issues, but the explanation as to why they solve condensation issues is never revealed, thus the science (physics) isn't spread to those people who could make this information common knowledge. Vented over-roofs in northern climates are a reliable solution for eliminating ice dams providing the venting doesn't become blocked.
Thanks guys for the info.
Hi. I've been watching some of your videos, and have a serious question for you. I have installed shingles, metal roofs quite few times, but recently, I've found myself in a dilemma. I recently bought a manufactured home, single-wide 16' x 80'. I replaced the original gutters with 5" k-style aluminum house gutters. Although it has no leaks, I want to do some preventative maintenance to insure against potential future leaks. This home has a slightly-pitched gable style, "loose roof" in that it is attached with staples at edges. My dilemma; should I use a 100% silicone roof coating such as Henry's, or metal roofing? I have a friend that is a professional roofer that suggests completely covering my entire roof with peel & stick, ice &water shield, then stripping (furring) it out, and installing the roofing metal. I'm very concerned about condensation using either method. The roof has no eaves therefore no soffits for vents. I'm concerned about my existing roof developing condensation problems, wetting my insulation, mold, mildew. Can I get you opinion on this please?
2 yrs later
Very interesting as I’m considering putting a metal roof over my 18 year old asphalt roof. (Seal the inside from the attic space)😊
What is the difference between the standard metal roofing with exposed fasteners that i see on many buildings, and standing-seam metal roofing that seems to be more expensive?
Standing seam metal roofing has hidden fasteners which aren't in contact with the elements like exposed fastener metal roofing. To learn more, check out this video: bit.ly/exposed-fastener-vs-standing-seam-revisited-video -Thad
great ... 1) what if the humidity outside is greater than your A/C'd climate controlled interior where the outside humidity wants to get inside the house ??? 2) Even an open metal building gets water dripping from the underside of the rook panels ...
I think you kinda missed it on this one as my only takeaways were condensation is bad, seal up your can lights and use common sense - duh!
I live in a manufactured home with a low pitched gable type metal roof. This roof is referred to as "loose roof" in that it is just attached by staples around the edges, everything in between sort of floating. I have no leaks, have just installed 5" K style house shingles. My question; to future-proof the roof, would you suggest covering entire roof with peel & stick, ice & water shield, then screw my wooden lat strips (1"x4" or 1"x6""), which I'll crosscut 1/4" every foot on the peel & stick contact side, through the existing metal roof and peel & stick to existing rafters, horizontally at aprox 2' OC, then install 29 gauge metal roofing? Or roll my existing roof with Henry's 100% white silicone, high reflectivity roof coating with limited lifetime warranty? The comment was made about covering en entire roof with ice & water shield creating condensation, so now I'm wondering which would be best. Please bear in mind the fact I live in Alabama where summer temps can, and do, regularly reach triple digits. Your advice will certainly be appreciated
What about artric roof exhaust fan
Do you have a video on valleys, ridge caps, and skylights/other things that extrude from the roof? If not, can you make one?
I n the USA the roofs of houses have ply wood & shingles but other countries they use clay roof tiles for houses which are cheaper to maintain than sheetmetal roofs , for example transportation, replacement of full sheets is becoming too expensive than individual clay tiles being replaced.
As can be seen by the numerous questions asked and unanswered, videos like these provide a content the author gets paid for by the number of times they are watched, but the author doesn't care about their audience or their input. They only post and forget for the money.
Thanks for the heads up. I won't watch.
This was an excellent presentation . . . Chris . . . Norwich, England
Thanks, Chris! -Thad
Thank you.
So what’s the answer to the problem?
I have a open carport with no walls or gables. It's raining underneath in cold weather. You said right just make some lemonade , then figure out how to make it out of wood....
The condensation problem (on the underside) arises from the top side of the metal roof facing the night sky. The night sky (especially on clear nights) causes the surface temperature of the metal roof to become much colder than the ambient air temperature because the temperature of black deep space is hundreds of degrees below zero. The severity of the condensation increases with flat roofs vs. pitched roof surfaces. Please be aware that the degree of condensation isn't as severe on cloudy or partly cloudy nights. Simply stated, physics dictates that more moves to less to become equal. The top side of the cold metal roof causes the underside of the metal roof to become cold enough to reach the dew point because of heat transfer (conduction). The dew point is the temperature at which water in vapor form condenses into liquid water droplets. Depending on the outdoor relative humidity (rh), there is a very good likelihood that condensation is also forming on the top side of the metal roof (not a problem). An example of surfaces facing the night sky is morning dew on the grass, but not on the grass under the leaves of trees due to the fact that grass under the 'shade" of the trees does not "see" the night sky. Another common example is car surfaces that face the night sky (i.e., hoods, tops, etc.) incur more condensation than the vertical surfaces (i.e., door panels, door windows). In northern climates, river water under bridges is the last to freeze because the water under the bridge does not "see" the night sky. Eventually, the continuous below freezing air temperatures do freeze the water under the bridges. Going back to metal roofs, when you think about it, it's really simple physics, but I never see this explanation from metal roof "experts." Why is that?
Our house house has a corrugated tin roof on the back addition. No installation on the roof and it's loud can we install installation a vapor barrier and drywall on it? To make a ceiling?
I'm building a new home with ICF walls from footing to top of wall and from everything I've heard and been told this is more or less an airtight system.
I plan on installing vaulted trusses 5/12 outer and 3/12 inner with 5/8" decking and all the sealing products then a breathable underlay beneath the steel and to my thinking is that with a vent ridge cap that would vent the roof no matter which way the wind blows.
Inside I plan to spray on a 2-3" closed cell foam to address air leakage and moisture issues. Since it is a new home it will need a good air ex changer anyway and one could then vent into the 'attic' and draw/control any moisture that gets into the space and not have to worry about venting already heated or cooled air to the outside. It is in a dry zone in the lower portion of Alberta Canada and humidity is really not an issue.
Would there be any condensation issues in a semi-conditioned attics (w/ open cell spray foam insulation on underside of roof deck) - also in the Alabama? Architect is saying no ice and water shield and no gap b/t standing seam roof and deck necessary - only a synthetic underlayment. How do you recommend installs with spray foamed roof decks / attics?
Generally I'd recommend closed cell. The closed cell acts as a vapor barrier while also providing good R Value.
@@asktoddmiller Thoughts on adding a vapor port at the ridge with a ccSPF insulated deck? Seems to me to be a good feature for safety?
To many factors in the south lol we get all 4 seasons in a week. I can’t find a good answer either about spray foam and metal roof. I hear roof rot and wet roofs . Then I hear spray foam is best thing ever. But can’t find any real science for that combo in the south.
@@JS-zb1vv That is exactly where I am at right now. I am building a house and they did Galva loom metal roof directly on top of the 2 x 4 strippers on the rafters. I was considering spray foam but it seems like it it is almost still like the Covid vaccine everybody has a different opinion.
Did you ever make a decision? I am meeting with a spray foam guy right now to see what he has to say
@@mxermatt1 I just put spray foam in my parents house. Closed cell in walls and open cell in attic. They have a metal roof. Only had it for 2 years so far . Probably to early to tell. But it is very very easy to heat and cool . I will absolutely make sure the window seals are protected well. Because the windows will condensate. I hope it was the right choice. Good luck because I talked to 3 foam guys and all were different. But there isn’t any real science with this . Even these guys making videos won’t answer these questions.
The video never addressed the title
Didn't you hear, put a glass of lemonade on your roof. Problem solved! : )
Lots more questions than answers.
Thank you for saving me 14 min
Thanks Todd
This is what I want to know: I am rebuilding part of my barn. I am just stretching 9 foot long 2x6s over a span and putting metal roofing on the top of these spaces out 2x6's. My question is if I should put plywood over those 2x6's in between them and the metal roofing? I really want to keep the weight down.
*Spaced out 2x6's.
just where is the metal roof piece?
Put a breather type building paper under the iron problem solved simples
I can picture a spray foam building in 20 years with the foam turning dark yellow shrinking and pulling away from surfaces
Another (expensive) way to solve the metal roof condensation issue is to build a vented over-roof to prevent the metal roof from being exposed the night sky. Vented over-roofs are often a reliable solution for condensation issues, but the explanation as to why they solve condensation issues is never revealed, thus the science (physics) isn't spread to those people who could make this information common knowledge. Vented over-roofs in northern climates are a reliable solution for eliminating ice dams providing the venting doesn't become blocked.
Closed Cell Foam under roof sheeting, Peel & Stick on top of roof sheeting, air gap then metal roofing, and an ERV unit. 100%
What are your thoughts on steel roofing panels installed over strapping on rafters - no plywood/or underlayment?
On a channel I've enjoyed watching, they've constructed a post & Beam home....love the basic design, but thought the roof was way to risky on the condensation front: (Current Moisture issue: ruclips.net/video/C2LveKCyRuk/видео.html, install of steel roof: ruclips.net/video/ByE7JgZHK-E/видео.html). It seems that he did a great job separating the in-home sources of condensation from the attic space, however my concern is frost/and external sources of condensation. Please speak about your thoughts on this issue. I'm a steel roofer, and personally always recommend underlayment on plywood for new construction with a home.
I am finishing a bare bones attic and noticed a little moisture on the insulation. I pulled a piece down there was a piece of foam in between the rafters, pulled that down and I was shocked to see the metal roof. By the end of the day there was about 20 leaking spots that were visable. I'm from Pennsylvania and never heard of a roof done this was. If anyone sees this and has any tips or tricks to help rectify this problem it would be greatly appreciated
@@dippy-egg The entire under-steel-roof-condensation issue is related to "moist air flow", and cold steel. Just as when you take a "cold glass" of something out of the fidge, it quickly forms condensation, the same principle is true of a steel roof. In the evening your roof gets cold (or sometimes the day if you are in a cold climate). There are two basic ways roof systems are designed: Vaulted ceilings underneath (insulation with no air flow), or "cold air under", roofs. the "cold air under roofs" is the most common, and rely on venting at the eaves which permits "cold air" to enter, and upper venting to allow the "warmed air" to escape. The principle of "cold air under roofs", is to keep both sides of the roof material at cool temperature: for shingles, this helps to cool the shingles and make them last longer, and for steel, it is supposed to ensure that the temperature on the upper surface and lower surface are similar... and hopefully are not hovering around the condensation temperature range. In practice however: all "cold roofs" eventually hover around the "condensation point", and thus condensation will form in some conditions. The idea behind interior home "vapor barrier" is limiting the flow of "moist air" past a "cold surface". The problem with this kind of flow, is that as the moist air passes the cold surface it will essentially "rain condensation" on to the cold surface. This is how de-humdifyers work: they make a cold "coil" of copper pipe by pumping a refrigerant through it, and blow the "moist air" past the cold surface. The moisture condenses and drips' off. So basically what I'm saying is: It almost sounds like, by removing the foam" you described, you introduced a flow path for "moist air" to pass by the cold steel roof.
Underlayment should have been installed under the steel roof. However some folks don't do this to save money. I personally don't recommend this installation method and would recommend installing underlayment. However, that can be expensive. It is basically 2x the cost of installing a roof: and potentially more if the installer elected to use seams between the installed steel (if they sealed/caulked the seams then removal would likely result in destruction of the steel panels).
If you recently opened up an "attic hole" under your roof, then you likely introduced a big opening and path for "moist air" to travel under your roof and condense under your roof. If this is the case, this opening should be closed regularly, and only opened for access. The air that travels under your roof should come from outside (cold/dry), and flow up/out the vents (in and up rafter vents, and out the peak vents or gable end vents). If you have a leaky ceiling that permits "cold moist air" from your living space to flow into the under-roof space, these holes should be stopped/sealed. If this isn't' the case, you could add a forced-air vent fan in the attic to improve cold air flowing from the underside of the roof..... Another potential problem that you could have created is the access of cold outside air from flowing in and under your attic space. Air flow paths should open from the eave of your roof up into the attic space. "Moore vents" are typically used for this. a Moore vent can be either "foam"/ cardboard, or even created with wood (see here: www.energystar.gov/campaign/seal_insulate/do_it_yourself_guide/adding_attic_insulation/installing_rafter_vents) . If this is the the "foam" that you are referring to, then your removal of them would basically permit the insulation at the eave to stop air flow, and then you would have created your own problem...
Not sure if this helps...but with no pictures of what your issue is...I'm kind of just guessing>>> Cheers Graham From WheelerSteel.ca
Was that Thads casting couch from his other channel... 😆jk just trying to keep it light. Good meat and potatoes metal roofing video as usual! Thanks Thad!
So essentially roof, siding and living space all have their own venting systems. The moment you introduce moisture from one to the other it’s a potential problem.
Does the radiant barrier help with drying out condensation and what are the chances of dust reducing its radient efficiency?
Consider the use of ridged foam sheet insulation. If it’s installed properly & is thick enough, water vapor will not condense & cannot pass through. I like polyisocyanurate .
These guys covered all the problems but offered no solutions. Very frustrating video. I learned nothing
Install ice and water barrier on entire roof deck, it makes this video pointless to watch unless your into the science of it all
@@ryanspence7239 can I use the smooth ice and water or do I have to use high heat ice and water
@@ryanspence7239 I used ice and water shield 3/4 of the way up my 9-12 pitch roof and then warrior #30 felt roof paper the last 1/4 of the roof. I was told not to go to the top of the roof with the ice and water shield because it won't let the house breathe and cause condensation. I also will have cathedral ceilings so the only venting will be out through the ridge.
You showed no layers. After each example discussed, you should have shown us a stick fire sample or diagram, something...otherwise it's a could be word salad that we are trying to imagine such as the wrong time to use ice and water shield sounds just like when you should.
A reason the inspector has to be able to see the layers,nit just as proof, and not just told an R-value as described.
Thanks
would fans help?
Almost every comment is a question....with no replies?????
Lots of good advice here. Ice and water shield is OK for the lower 4 feet of the roof. Covering the whole roof is a mistake. If you have an interior vapour barrier or foamed roof, you have just created a plastic mold sandwich. Tar paper works well, is time proven, and cheap!
I think you are making incorrect statements. People should NOT be using polyethylene plastic in walls or ceilings. There are other products that should be used when facings are required to control vapor migration. There are engineered products like Intello or even Kraft paper. Secondly, ice and water shield is supposed to be used only at the eves and valleys preventing ice dam damage and possibly around skylights whereas synthetic underlayment should be predominantly used. Focus on air barrier to prevent air moving into the home.
Cool cool...just got into argument over co worker on this...and so far everything I searched he was wrong...and he's the foreman lmao
Anyone here use Reinke aluminum shingles?
Intro has me watching.
"LET'S FACE IT: A LOT OF BUILDING MATERIALS THAT WE USE DON'T BREATH A GREAT DEAL"
OH DAMN. YOU CONFRONTED IT HEAD ON. I HAVE BEEN LYING TO MYSELF FOR YEARS ABOUT THIS, AND THEN YOU GO SPEAK THE TRUTH IN THE PUBLIC LIKE THAT. I FEEL SO VULNERABLE. SOMEBODY HOLD ME. THIS GUY DOESN'T HOLD ANYTHING BACK. WATCH OUT!!! HE'S A WILD ONE. TRUTH TO POWER. EPIC HERO. FOR BIDEN'S SAKE, IT SURE IS GOOD HE ISN'T IN GOVERNMENT, BECAUSE HE WOULDN'T LAST LONG!!!!
I get more confused 😕
I think the age-old belief that “A house needs to breath” is not the case when it comes to Batdominiums & possibly other builds !
The audio might have been better if you didn't lay your recorder on a rock hard table...
The audio sounds pretty good to me, but I'll take a look at different mic techniques next time we record. Thanks for the suggestion! -Thad
@@TheMetalRoofingChannel
There's a lot of sibilance or harshness. If you're not hearing it you may look into getting a new amp, speakers or headphones. (Or someone with their hearing intact...)
Putting the mic on a stand and putting some acoustic foam/matting down on the table may help.
I've checked this out in multiple listening environments and rooms i.e. headphones, studio monitors, laptop speakers. I might have had the exciter set a bit high in my mastering chain and probably could've pulled down the 10k range with the EQ/used a de-esser. You can see on the right side of the screen I am running multiple microphones, so the recorder itself is only providing partial audio anyways. If it sounds harsh with your setup it's more likely a post processing issue rather than a mic issue. I'll look into that for future episodes as well. -Thad
@@TheMetalRoofingChannel
Make sure the microphones on the recorder are actually turning themselves off when you plug an external in.
See "The Tascam DR-05 audio recorder is a horrible device" by louis rossmann.
horse shit. I have a white roof on an open barn and it condensates even in winter....5 miles away ,my other gray roof barn doesn't
Blah blah blah
Something different you'd like to see? -Thad
@@TheMetalRoofingChannel why didn’t you show cross sections of ventilations for different styles of problems. Plan drawings of ventilations styles for all the types of problems that occur would have been better than talking about the problem. Being almost a Jr Architect and was on my way to being a AIA Architect, I stopped and went to a different career path. Drawings/pictures or diagrams to that show the fixes or the problems to show a clientele helps better their understanding not your ability to talk about it.
@@urf808 Noted, drawings would have been good to show in this video. Some of our recent videos incorporate those type of graphics more readily. Always looking to improve! -Thad
Here's an idea, dont use metal and you dont have to worry about water condensation rotting your roof 👍
WOW! A lot of viewer questions and so few answers. Why would anyone want to subscribe to your channel? SMH
A Whole Bunch Of TALK, With NO Pictorial Examples Of What They Are Talking About. NOT Very Interesting. This Video Must Be Made For Metal Roofers, Already Dealing With Instillation Concerns.
If people air seal and insulate properly, this whole conversation becomes a non issue.
Hi. I've been watching some of your videos, and have a serious question for you. I have installed shingles, metal roofs quite few times, but recently, I've found myself in a dilemma. I recently bought a manufactured home, single-wide 16' x 80'. I replaced the original gutters with 5" k-style aluminum house gutters. Although it has no leaks, I want to do some preventative maintenance to insure against potential future leaks. This home has a slightly-pitched gable style, "loose roof" in that it is attached with staples at edges. My dilemma; should I use a 100% silicone roof coating such as Henry's, or metal roofing? I have a friend that is a professional roofer that suggests completely covering my entire roof with peel & stick, ice &water shield, then stripping (furring) it out, and installing the roofing metal. I'm very concerned about condensation using either method. The roof has no eaves therefore no soffits for vents. I'm concerned about my existing roof developing condensation problems, wetting my insulation, mold, mildew. Can I get you opinion on this please?
Where is the home? Big difference in the answer. I'm in New York and after fixing my gutters and having them ripped off again for years, finally decided to take them off before winter. I might put them back up in the spring, I dunno.
@@jamesvandamme7786 My home is in NE Alabama