@@HAWAYP it depends on the siding type and how your wall is built. Ours was already built as a garage with 2x4 and sheathing. As per the installation instructions from the roxul manufacturer, you apply breathable wall wrap (tyvek) then attach your 2x2's every 12/16/24", insert the roxul panels ( not batt type) then side over that attaching to the 2x2's. It's highly effective having that outter layer especially if in most places the furring 2x2's don't match the studs from the original wall, this further reduces thermal bridging. Some places may also want a rainscreen integrated into that but it depends on the area and local rules.
This is so cool. My wife walked past while I was watching the video and she said "Great, your going to rip all the siding of now and put that on the haous now, aren't you" and I said "Maybe, maybe not" depends on the comments.
We have a 50 year old stucco bungalow that's like living in a barn, I can see daylight in some places. Re-building it is silly, what it needs is a layer of insulation (the fireproof rockwool) over the stucco (exterior) and then a light weight siding of steel where there is sun, or wood where there is not. Now, the 1" thick stucco has the same volume of concrete as the 4" slab under the house, but it's outside, where it gets super hot by day and holds that heat against the house until mid night sometimes. Worse than a fur coat in summer because it holds heat energy like a battery. There are a few other houses around here like it, maybe a million of them. The Rock wool is just thick enough that it isn't self supporting, you need something like steel stud framing to hold it in place and hold up the siding. The studs shouldn't be connected directly to the stucco, any thermal break will help. This is an excellent opportunity to add a radiant barrier over the insulation but under the furring or hat channel strips needed to attach the siding. Capturing the mass of the stucco inside the envelope will help but not that much because of how it's distributed, and any insulation, or drywall inside that covers it, (stud cavities) would have to be removed. But negating it's heating effect outside, and adding the radiant barrier to the exterior walls, will make a significant difference. ($$) Not enough to do the walls only, roof is next. And everything we do now, has careful attention paid to the fastening system. Cat 5 wind resistance is "sustained winds at or above 156 mph", so we should be ready for that minimum. For the record, I'm going to attach some plans for a complete energy retrofit and sell this barn, then build something small and efficient. I'm too old for the renovation game, but I see lots of fun ahead designing for our future.
Yeah very old topic but I have recently discovered... The real game is leave all the existing siding and "water proofing" right where it is. Add a couple inches of Rockwool over the top, add rain screen siding, retrim around windows and doors and there you go. Considering this in WUI area myself for both insulation and fire survivability reasons.
I installed blown in RockWool throughout my two story house. Very good. Extremely sound proof, and when I put map gas to it, it only glowed until I removed the flame, then grabbed it by bare hand! (Did it to show my friend who is a fire chief).
Good video on the Roxul product. What would be very useful is some content on the details. How do you finish out around windows and doors? How about ties for the stone exterior? What about wall penetrations and how they are sealed? Finally, what additional wall insulation was used?
+DaveC thanks for the ideas Dave! I'll work on those. Stay tuned for a video next week on how to finish out the windows with a thick exterior Roxul install
@Phil Perri it's sad that many different product(S) are made in a toxic/harmful ways. Why the companies making them don't think a long term future/goals?
@@buildshow : I've looked for the follow up video and can't find it. My main question that I don't see answered is did you also insulate between the stud cavities as you normally would? I would say for sure because the more the merrier right?
I don't think it beats fibreglass by very much for R value and noise reduction, but it handles moisture a lot better. (Not as good as foam, of course.) It doesn't wick moisture or lose R value when wet as much as fibreglass does. I can also work with it without gloves. It doesn't stop mice, but I don't think any insulation does. Apparently it's a lot better for the environment than fibreglass and foam as well, and it's pretty easy for us DIY types to work with.
Would be nice if Roxul supplied fasteners or suggested fastener products for comfortboard. Getting product is doable, but fasteners not so much. Like the all-in-one rainscreen wrap you have over comfortboard. A real fan of Roxul...so many positive benefits to using it.
I use the same material on exhaust system, boilers, steam systems forced Draft blowers ect. In the marine, commercial and industrial trades. But 6 to 24 inches thick. It's a pretty good material.
I see this video was released in 2017. I just heard of this product on a Pro to Pro video from This Old House December 2019 where they talked about it (for the first time I believe)....Good work Matt!
Roxul (rockwool) is standard practice up here in Canada. We have been using it in installations for at least 30+ years. It is far superior to fiberglass for any installations where you might get water penetration or moisture buildup as it completely dries and doesn't lose its insulation value. As mentioned, it is completely fireproof and also doesn't sag at all in wall cavities. Its also rated for firestopping here as well. Excellent product.
Yes, I've watched many videos and read a good bit and am really impressed with the properties of the Roxul , Rockwool, whatever it's named. Relatively reasonable price too.
I have roxul r15, and r23 on my house with 1” foam. It is an 800 sq ft tiny house and I spend $120 for heating on my house for The Whole winter on NE PA. I wish I had the outside board when I redid all the outside walls! I am going to have to keep my eyes open later down the road.
thats awsome. I am heating 2200 sq ft (unfinished basement and ground floor) for about 300ish - in reality its more because i pay 17$/monthly just for NG access. No insulation on walls or at least very minimal, R60 attic. Just insulated rim joists and basement for this winter. Would love to tear out my walls and insulate the whole thing :D - Winter season i just checked. From October to April - 310 therms which NG is roughly 240$ just in gas (add the 17$/monthly) - not bad! Granted I turn off my heat whenever we leave the house and decrease temp to 60F at sleep time.
This stuff is amazing. Many uses for it. I’ve even seen this installed in thin walls for some kind of sound proofing versus none. I 100% agree with you Matt on the insulation on the house side. This should be common building practice.
They make a denser insulation that can't be purchased at home centers which is excellent for sound absorption, i made some acoustic panels for a recording studio using it... works amazing.
In Norway we have used this stuff for 70 years.. xps or foam is illegal due to fire hazard, we also have this stuff caled Glava that is made from glass, it's easyer to work and dosent burn or mold. Our houses here often have 1,5 by 8" wall studs, with glass wool. On the innside we use plastic film to block humidity. then 2 by 2" with glass wool and also room for tecnical installations without breaking the plastic barrier. On the outside we have asphalt sheeting, then tyvek vrapping + 20mm "clamping" studs. then 2 by 2" cross brasing before weather shield or cladding.. You get 60mm of air gap between the tyvek and cladding.. this makes the heat stay out and the building stays dry due to the air sirculation behind the cladding.. you should try this on one build :)
I'm sold. This is the 4th product I'll be buying thanks to this show. My zip board is already on , now for several reasons I've decided to add exterior insulation. The fire rating, using strapping lets me lower my starter strip, the extra insulation and extra water barrier. Rockwood wins because they have incredibly detailed easy to follow instructions, 100 pages for every situation imaginable. I'm not a pro builder so this is incredibly valuable to me to get the job done right. Products I've bought because of build show, Zip, Cavity slider, and coming soon, Steller flooring and Rockwool.
Great demo of those mineral wool boards. I see a lot of passive house builders using dense packed cellulose in exterior cavities (between the air-sealed plywood siding and the house-wrap). Seems like adding mineral wool on top of that would be ideal, adding fire protection and extra water resistance without compromising outward drying potential.
Another great video Matt. I bought Roxul insulation to finish my basement from Lowes, the only place I could find that carries it.. The big question is why we haven't replaced fiberglass use with Roxul in US.
In the video, it appears the rock wool is NOT exposed, and it is covered with yet some other facing product. No mention about if that facing also fire proof? if not, wouldnt that be a weakness that would need to be addressed to be part of a 'complete solution'?
We had an issue with Roxul and the use of masonry veneer. The manufacturer of the masonry anchors wouldn't certify the connectors for buckling for the lateral earthquake forces. Rigid insulation stabilizes/braces the veneer anchors from buckling but you don't get that effect from Roxul since it is softer. If you are using stone veneer, what kind of masonry veneer lateral anchors are you using and are they certified (for seismic/wind forces) with the use of the softer Roxul material.
Double Dare Fan Why? He said it’s good up two thousand degrees, and an acetylene torch gets over five thousand degrees. Maybe look cool but proves nothing.
I tired to burn/set on fire regular fireberglass insulation with a MAP torch and it would not catch on fire no matter what. I had some scraps from working on my bedrooom and trash can was full so why not :) I dare to say that fiberglass insulation is maybe not fireproof but it's fireresistant?! Anyone want to comment on this?
@@uhighsmith The problem for me was that it was an informal demonstration of something that needs a formal demonstration like one would get in a UL fire test lab. I suspect that the rock wool type insulation would do spectacularly well in that kind of a test but Matt's demo didn't really prove much. I notice somebody below tested it with a MAP gas torch. That seems like a much better test than Matt's because it is much closer to testing the material's resistance to the kind of temperature and heat it might experience in a wild fire or a house engulfed in fire.
Great video! Exactly what I was looking for and wondering about, and I now feel comfortable making a decision to go with Roxul for exterior insulation. On the "4 things that I really like about this" at 6:40 - maybe one of "fire resistant" and "non-combustable" was intended to be minimal drift in R-value, in part due to the minimal contraction/expansion discussed at 2:50? (That was something I didn't know about and definitely appreciate.)
Matt, traditional stucco systems use a “chicken wire” lath (17 ga or stronger) which is stretched over the side of the house with fasteners. I was wondering, is the synthetic lath ridged? Is it fire proof? Such a lath would transmit any lateral movement of the stucco membrane uniformly and probably result in fewer cracks resulting from minor earthquakes. I love the idea of stucco over Roxul. This totally makes sense especially on the side of a house which is in close proximity (12 feet) to a neighboring home. Provided fire fighters got to your home quickly enough, and there was no severe eve damage, you could be good to go with just another coat of paint over the scorched stucco membrane.
FYI: Rock-wool or Mineral-wool (brand: Roxul was featured) is NOT a new product and has been out for many years, and now even Home Depot & Lowes carries it. I've used it on many projects and always had huge success with it.... better R-value, easier to install, fire-proof, water-resistant, and much better sound-dampening properties. It even works great for Tiny Homes and guest homes.
That's right! I started using Roxul (now called Rockwool) when I did my house build in 2011. We also use the comfort board for sound absorbing panels covered with fabric in recording studios. That said, the batts I pulled out of my house where from the 1950s mineral wool batts, so I am assuming this has been around since before the 1950s.
Matt, love your videos. According to many experts the cause of the London Grenfell fire was not the insulation but the ACM panels because they were made with non-fire rated core which does not meet building code in London or here in the US. Plus they designed with an unusually large air space in the cavity. I like mineral wool. But not all foams perform the same. Polyiso doesn't actually burn it just chars, Extruded will soften and melt at low temps.
My understanding was the London fire was Aluminum Composite Panels which is sold in sheets 4mm & 6mm thick, then fabricated into different size panels or shapes (most car dealerships). These do not include any insulation or thermal value. You might be thinking of an insulated metal panel which is insulation sandwiched between 2 exterior metal skins.
After some research I concede you are correct on the ACM. I was thinking of insulated metal panels. It does turn out there was also highly combustible insulation directly on the wall, so I guess in the end insulation was also a factor ;) www.fireengineering.com/content/dam/fe/online-articles/documents/2017/Grenfell003.pdf
ROXUL is noncombustible and rated beyond 2300dF upper temp limit. The mineral wool used for thermal and acoustic applications in walls and cavities is light density normally between 2.0-3.0 Pcf and is semirigid. The 8 Pcf material featured in the video is the same material however produced at a much higher density resulting in a rigid product that indeed is much more water repellent compared to low density batts allowing use in exterior applications. Great product and you can run a burner under a section of the mineral wool for hours without any effect nor heat transfer to the opposite side. One point from the video to clarify would be that polyiso foam panels which normally come with foil facers for exterior applications are self-extinguishing when exposed to open flame either to the foil surface or the closed cell foam surface itself. Polyiso also has an R value which is higher than mineral wool or fiberglass that does diminish slightly as the panels age as noted in the video however this occurs only to a minimal degree as the panels lose some of the pentane gas which is introduced in the foaming process and this gas remains trapped within the closed cells for the life of the panel giving the polyiso a higher rate of thermal performance per inch compared to most every other form of thermal insulation. The LTR (long term r value) of closed cell polyiso is published by each manufacturer taking in account the aging of the panel as it sheds a small percentage of pentane adjusting to the surrounding atmospheric pressure for the region where it is situated. When produced R values of polyiso per inch of thickness are commonly stated as high as 7.1 and settle after some weeks to be between 5.8 and 6.2. Once the panel settles to this level it balances and does not continue to lose thermal value, Compared to thermal values between 3.8 to 4.2 max per inch for fiberous insulation products such as f-glass or mineral wool at the same 1" thickness closed cell foams are superior in this regard. Also being closed cell there is no risk of moisture ingress or damage and the foam also provides no form of sustainability for mould or fungus growth.q
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Great videos as always. Just one question, how will you be attaching the exrior final facade/siding? Layer of Rockwool is obviously not structurely strong enough. So would you use some super deep and strong fasteners that would go throught rockwool and into the studs? Would love to see the scheme of your wall design.
I watched this to see what was being applied over the mesh. Like the design! Stopped by another contractors build to speak with a sub and noticed they were using 1/4" Barricade Thermo Brace in lieu of OSB on the exterior?? Is that even sturdy enough on 10' walls to Brace against wind loads???
Rad. If you switched to a hardi board siding for this assembly, what air gap product would you use on top of the roxul? And how the heck would you fasten down the siding?
I'm curious how the stucco will go. It seems like you could just push on the stucco and have some flex... Also curious how you might do siding over this? Maybe some z-channels?
+Matt Metcalf Matt, great question. We are doing a traditional 3coat stucco with this synthetic Lath system underneath. It's should be very rigid. Think vertical sidewalks or sheet Hardie. I think a video on this might be a good idea
david miller that was exactly what I'm thinking. I currently relocating to a small town and in taking over the care of three older homes that are all shiplap siding. More than that is I'm actually looking at a seventy-five-year-old home with hardwood siding. This home needs a major remodel. This would include two small additions.
Your video title is Rockwool Exterior Insulation vs Rigid Foam however you didn't say anything about the rigid foam insulation but god information about the Rockwool insulation.
Comfortboard is significantly more expensive than rigid foam sheathing. Additionally, some sources claim it is dangerous to health. A video report of a comparison of fire resistance suggests that wet-blown cellulose in the wall bays is comparable to mineral fiber batting.
Putting this blanket on the outside of the house, the holy grail is insulation that is fireproofed. I wonder if exterior insulation can be implemented with airkrete. And how feasible it is with the current installation methods they offer.
Did u cover in later vid how the trim detail and fur out is sealed to the recessed windows? I know u said this house will get lower stone veneer and upper stucco so maybe not to much trim detail was in the design. Either way a link would be appreciated. Keep the great info coming Matt!
Great video, but I have even more questions now! My house exterior is a mess. It is aging 3-coat stucco that had been painted (badly) and there is no wood sheathing -- just celotex (spelling?) fiberboard then the stucco. Is there any reason that the exterior couldn't be replaced with first putting rockwool bats inside the wall cavity to replace the old probably-droopy fiberglass bats, then rigid rockwool as both sheathing and insulation, then finish with a one-coat stucco? (no membrane, no wood sheathing) The first contractor I spoke to wanted to put the foam board (the exact brand that was on that apartment building in England!), then a wrap, then 3 coat stucco. Listening to him, I felt like I'd be jumping from one frying pan into another at the very least or worse -- jumping from the frying pan into the fire (perhaps literally).
I have two pallets of the 2" R8 next to my house getting ready for the reno which includes new windows and resheathing the entire house due to no WB installed when it was originally built, going with a peel&stick product.. need a few more items before I begin
The air gap materials are really interesting, I was/am planing on doing a rainscreen w/ furring strips of wood or maybe corrugated plastic (must be UV resistant as there will be exposure from an air gap in the siding, similar to the Ipe setup)
Yes, as much as I can by myself. May need help from a friend for the new windows (due to high traffic) are sound dampening ( 45 STC ) and are basically two windows in one (Milgard QuietLine) and thus very heavy.
Planning my new build… what are the envelope layers to add, in order from OSB out? I plan to keep the 2x4s and copper spiral ductwork exposed on interior. I am going to use rockwool as the envelope, but I need to keep costs down (no stone exterior)……………. Recommendations are appreciated.
Roxul - Rockwool is what I've looked into. [same] - Soon, i hope, to find a person to build Gabled Roof Frame over back room to meet original house's. [replaces rotted flat roof] Question - I was Wondering HOW to Place it Against the Inside of Lap Wood Siding of back room ['60's] & Attic [1920's] Walls. Nothing had ever been placed there (Fla. House) - Roaches Crawl in, Not willing to crawl out. =6 What is Needed Against Wood BEFORE Rockwool? Thanks much! ~ just wish my brain Knew Long ago. [books then lacked this] Learned last week, from you, about ability of Back of Wood to Dry out - hence - Nothing, I noted that blown insulation - now in outer walls, [28 yrs ago], I think has caused Paint to pop off in areas. [not to mention it's Over Active Knob n Tube Wire, a no no later learned] =|
Matt, on a build if you're putting 1.5 or 2" of comfort board on the outside would it matter much if you used batt or blown in fiberglass between the studs. Or does it still make a big difference having the better insulation between the studs. zone 4 southern Vancouver Island. Thanks.
Hi, great explanation & demonstration! Thank you! :) For a 45 yr old manufactured home in Nor-Cal (Sierra Foothills) how much Roxul would you suggest using & where? I want to remove the panels inside and replace with either thinner plywood, bead board, or thinner drywall.
I Have an old house with leaky (air and moisture) board and batten siding and no house wrap. I have exposed some of the exterior walls from the inside and am considering insulating. Concerned about mould and rot, could this product be used in the wall cavities and allow for the board and batten and studs to breathe and dry out if they get wet?
lol. I like how you use a tiny lighter to prove its flame resistance. Having said that, I do like this type of insulation... I'm more familiar with the cavity type insulation, but still looks interesting. Question I have is , the delta drainage plain... how fire resistant is it ? Is it also a special type to go over this type of insulation? Does the type of drainage material even matter ? Love your build with the lvl's on this house . 👍👍
i'm considering external insulation for my detached house in UK. Its a timber frame house with single skin brick. Not much space for internal insulation. The only thing I don't like is that it will leave the window recesses really deep.
Curious if you used it on the roof as well. Are you also adding insulation to the wall cavity as well? If so, what are you using? I am going to build a metal building workshop in liberty hill tx that has z-girts horizontally at 4' spacing. Is this rigid enough to be applied with only being attached at ends and middle? Will be covered by metal corrogated panel. I have Been considering whether I need the advantech sheathing since the bracing will be steel cable integral to steel frame. Looking forward to the answers to all of the questions in this discussion thread. Love your videos.
+Simeon Kessler my recommendation would be closed cell foam and skip the sheathing. That will add a ton a lateral shear, add water resistance, and provide great insulation and air/vapor impermanence
Matt Risinger. Since my land is full of live oaks I was thinking that having a layer of the roxul 80 would give me some protection against fire should a grass fire ever sweep through. I was planning on spraying a few inches of closed cell foam behind the layer of roxul to encapsulate the steel to prevent weeping from condensation, and give me air seal. Plus that creates a separation between the steel siding and the spray foam. Not sure what I should do for the roof assembly. It seems like decking with a peel and stick would provide a secondary drainage plane for when there is condensation on the backside of the standing seam metal roof. Have read on several forums that they recommend not decking the roof for metal but that seems like a gamble since all roofs leak.
AdvanTech on the walls is a great idea. My concern is if the rockwool gets wet somewhere how long would it take to dry being 2" thick and would you know if it was wet? This would not be a concern if the overhang was around 4' or so but builders don't want to make a proper overhang. I think closed cell spray foam on exterior walls over vertical galvanized metal channel to hold siding would be the best thing but haven't seen that anywhere yet! Closed cell foam does not break down and seals out moisture and prevents condensation because air can't get to the surface. Outside is the best place for foam and inside sounds like the best place for Roxul.
Another thing i should have added is spray foam has E84 fire retardant and is much better at keeping your house from burning because the fire can't get to the pine. Sorry but it looks to me like your lying about things here to sell your product.
Matt I am a Police Officer in VA. and I am remodeling a 1942 House in WV and was wondering if there is a way for me to air seal the 1X sheeting on the old part of the house with out braking the bank. I am trying to pay as I go
Where do you source comfort board 80 from? I'm in the Austin area and having a difficult time finding a supplier that doesn't have a 3 month lead time.
I’m a fan of Roxul, I installed it in a large portion of my house during a reno. But now my cell phone reception in that area is awful. Awful like can’t be in that part of the house on my cell phone because I’ll drop the call. Thoughts?
Matt, I just watched a video of the 5 worst things builders can do in the South and one was using Stucco. Why would you then use Stucco on this custom-built home?
Who manufactures the "green" layer under the mason-stucco layer is applied? I think you said "Borrell" or similar synthetic Lath system manufacture but the link seems to be missing. I'm in Scottsdale, Arizona. Temps reach 120degrees in summer. Dying to replace all my stucco. Also looking for info on J-joints and bug screen updates if needed where the wall meets the foundation. Thanks ahead of time! Great videos!
Can u find out about possible silica problems? Or why there is no risk of silica? Made from rock brings to mind rock dust and silicosis since I work and deal with rock dust exposure. Thx!
Is it possible to renovate an existing stucco home with this stuff? Would the existing stucco need to be knocked off first and what if the house only has small eaves? Would the eaves need to be extended?
So the rockwool goes to a couple inches from the window? And the window is surrounded with some sort of exterior build out so you have a nailer for sheathing? I dont see that happening. Wouldnt it make sense if the window flanges were attached to the mentioned frame.. and extension jambs installed?
the firm I work at spec rockwool all the time for the walls though we do tend to stick with polyiso for the roof due to its high R-value and weight. Our projects are all in the arctic and subarctic so we have very thick exterior insulation for walls and roofs... but I do wonder which approach is really best if we need to do multiple layers for either product (Matt mentioned rockwool being beneficial as you can use just 1 layer of 2"... maybe that works in the states but in Canada we are dealing with colder temperatures in most cities... and, again, the projects we work on are in the coldest places in the country). If anyone had any insight on this - if you're a builder or perhaps know of how these insulations perform over 20+ years... would be great to hear what you have to say!
If you are retrofitting external insulation, what can you do to ensure that you can replace soffits in the future and should you extend the apex of the house
Where can I find info on this that really lays out the details? For example, if it's 70F inside with 45%RH, and it's -10F outside, if you have R8 around the outside over an OSB sheathing and you're using drywall inside, what is the temp of the inside surface of the insulation and would it be below the dew point? What if you use this in addition to insulation in the wall? After all, R8 is not a lot. I hear people talking about it but nobody really touches on the actual science.
R8 is not a lot in colder climates, in Texas weather its probably descent. In Sweden where I live rockwool as we call it have been very common for decades. Both in the external type as shown in the video (it is far newer however) and the batt type inside the framing. The position of the dew point will vary greatly dependant on weather and quantity and type of insulation used in conjunction with the external sheets, in sweden moisture barriers are usually placed at ~1/3 of wall thickness measured from the inside. Often in a configuration of 2 layers of batt insulation with the vapour barrier in between the layers, and a 3 layer behind the siding.
Dew point matters less--a lot less than in rigid foam--in Rockwool because it is vapor permeable, as it can dry externally in the spring, summer and fall. If you're -10 outside, you're probably in zone 6 or 7. See this article, which will give you the R-value you need to hit based on your climate zone: www.greenbuildingadvisor.com/article/calculating-the-minimum-thickness-of-rigid-foam-sheathing
Is there such thing as to thick with rockwool? Lets say you double up or even triple u the layer? Would 4" or 6" or rockwool exterior insulation be to much?
R-value of 8 is insufficient to replace the need for interior cavity insulation. If my goal is to only exterior insulate and replace the need to insulate interior cavities, would I need to step it up to Comfort-Board 110, and if so, what is the R-value for Comfort-Board 110 (their website unfortunately does not list this). I'm in climate zone 3 where the minimum wall R-value is 13.
I've been using this for years up in Canada.. It works extremely well.
How do you install siding over rockwoll. Do you apply it directly or do you strap first?
Hi Michael, joining Matthew's question. how do you install siding over rockwoll. Thanks.
@@HAWAYP it depends on the siding type and how your wall is built. Ours was already built as a garage with 2x4 and sheathing. As per the installation instructions from the roxul manufacturer, you apply breathable wall wrap (tyvek) then attach your 2x2's every 12/16/24", insert the roxul panels ( not batt type) then side over that attaching to the 2x2's. It's highly effective having that outter layer especially if in most places the furring 2x2's don't match the studs from the original wall, this further reduces thermal bridging. Some places may also want a rainscreen integrated into that but it depends on the area and local rules.
This is so cool. My wife walked past while I was watching the video and she said "Great, your going to rip all the siding of now and put that on the haous now, aren't you" and I said "Maybe, maybe not" depends on the comments.
+Abby Babby that's hilarious!
We have a 50 year old stucco bungalow that's like living in a barn, I can see daylight in some places. Re-building it is silly, what it needs is a layer of insulation (the fireproof rockwool) over the stucco (exterior) and then a light weight siding of steel where there is sun, or wood where there is not. Now, the 1" thick stucco has the same volume of concrete as the 4" slab under the house, but it's outside, where it gets super hot by day and holds that heat against the house until mid night sometimes. Worse than a fur coat in summer because it holds heat energy like a battery. There are a few other houses around here like it, maybe a million of them. The Rock wool is just thick enough that it isn't self supporting, you need something like steel stud framing to hold it in place and hold up the siding. The studs shouldn't be connected directly to the stucco, any thermal break will help. This is an excellent opportunity to add a radiant barrier over the insulation but under the furring or hat channel strips needed to attach the siding.
Capturing the mass of the stucco inside the envelope will help but not that much because of how it's distributed, and any insulation, or drywall inside that covers it, (stud cavities) would have to be removed. But negating it's heating effect outside, and adding the radiant barrier to the exterior walls, will make a significant difference. ($$) Not enough to do the walls only, roof is next. And everything we do now, has careful attention paid to the fastening system. Cat 5 wind resistance is "sustained winds at or above 156 mph", so we should be ready for that minimum.
For the record, I'm going to attach some plans for a complete energy retrofit and sell this barn, then build something small and efficient. I'm too old for the renovation game, but I see lots of fun ahead designing for our future.
@BP what would you do then with window flanges several inches INSIDE yout new 500 year siding?
@@refusoagaino6824 a lot of specialty products will be born to compensate for these new techniques too. Moisture will always be the devil.
Yeah very old topic but I have recently discovered... The real game is leave all the existing siding and "water proofing" right where it is. Add a couple inches of Rockwool over the top, add rain screen siding, retrim around windows and doors and there you go. Considering this in WUI area myself for both insulation and fire survivability reasons.
I installed blown in RockWool throughout my two story house. Very good. Extremely sound proof, and when I put map gas to it, it only glowed until I removed the flame, then grabbed it by bare hand! (Did it to show my friend who is a fire chief).
Good video on the Roxul product. What would be very useful is some content on the details. How do you finish out around windows and doors? How about ties for the stone exterior? What about wall penetrations and how they are sealed? Finally, what additional wall insulation was used?
+DaveC thanks for the ideas Dave! I'll work on those. Stay tuned for a video next week on how to finish out the windows with a thick exterior Roxul install
Matt Risinger I also want to see that Matt! 😊
Ron
@Phil Perri it's sad that many different product(S) are made in a toxic/harmful ways. Why the companies making them don't think a long term future/goals?
@@buildshow : I've looked for the follow up video and can't find it. My main question that I don't see answered is did you also insulate between the stud cavities as you normally would? I would say for sure because the more the merrier right?
Phil Perri Sure Phil I wouldn’t mind seeing the stats. Can you post a link here?
Great product outside insulation with NO off gasing issues.
I don't think it beats fibreglass by very much for R value and noise reduction, but it handles moisture a lot better. (Not as good as foam, of course.) It doesn't wick moisture or lose R value when wet as much as fibreglass does. I can also work with it without gloves. It doesn't stop mice, but I don't think any insulation does. Apparently it's a lot better for the environment than fibreglass and foam as well, and it's pretty easy for us DIY types to work with.
Would be nice if Roxul supplied fasteners or suggested fastener products for comfortboard. Getting product is doable, but fasteners not so much. Like the all-in-one rainscreen wrap you have over comfortboard.
A real fan of Roxul...so many positive benefits to using it.
Cap nails, easy, cheap and readily available.
I use the same material on exhaust system, boilers, steam systems forced Draft blowers ect. In the marine, commercial and industrial trades. But 6 to 24 inches thick. It's a pretty good material.
Higher R value than fiberglass, excellent sound proofing for inside and outside walls, can be compressed still keeps high R. Also mice hate it..
I see this video was released in 2017. I just heard of this product on a Pro to Pro video from This Old House December 2019 where they talked about it (for the first time I believe)....Good work Matt!
Roxul (rockwool) is standard practice up here in Canada. We have been using it in installations for at least 30+ years. It is far superior to fiberglass for any installations where you might get water penetration or moisture buildup as it completely dries and doesn't lose its insulation value. As mentioned, it is completely fireproof and also doesn't sag at all in wall cavities. Its also rated for firestopping here as well. Excellent product.
Yes, I've watched many videos and read a good bit and am really impressed with the properties of the Roxul , Rockwool, whatever it's named.
Relatively reasonable price too.
I have roxul r15, and r23 on my house with 1” foam. It is an 800 sq ft tiny house and I spend $120 for heating on my house for The Whole winter on NE PA. I wish I had the outside board when I redid all the outside walls! I am going to have to keep my eyes open later down the road.
thats awsome. I am heating 2200 sq ft (unfinished basement and ground floor) for about 300ish - in reality its more because i pay 17$/monthly just for NG access. No insulation on walls or at least very minimal, R60 attic. Just insulated rim joists and basement for this winter. Would love to tear out my walls and insulate the whole thing :D - Winter season i just checked. From October to April - 310 therms which NG is roughly 240$ just in gas (add the 17$/monthly) - not bad! Granted I turn off my heat whenever we leave the house and decrease temp to 60F at sleep time.
what part of this vid shows the outside wall? I don't understand what you are referring to. thank you
This stuff is amazing. Many uses for it. I’ve even seen this installed in thin walls for some kind of sound proofing versus none. I 100% agree with you Matt on the insulation on the house side. This should be common building practice.
+lolMyke thanks!
They make a denser insulation that can't be purchased at home centers which is excellent for sound absorption, i made some acoustic panels for a recording studio using it... works amazing.
jon Q what's that product called?
Their website lists all their industrial products.
They way you make these informative vids are a true delight!
In Norway we have used this stuff for 70 years.. xps or foam is illegal due to fire hazard, we also have this stuff caled Glava that is made from glass, it's easyer to work and dosent burn or mold. Our houses here often have 1,5 by 8" wall studs, with glass wool. On the innside we use plastic film to block humidity. then 2 by 2" with glass wool and also room for tecnical installations without breaking the plastic barrier. On the outside we have asphalt sheeting, then tyvek vrapping + 20mm "clamping" studs. then 2 by 2" cross brasing before weather shield or cladding.. You get 60mm of air gap between the tyvek and cladding.. this makes the heat stay out and the building stays dry due to the air sirculation behind the cladding.. you should try this on one build :)
Rocksol has been around for at least 60 years! Great in the basement as well as the exterior. The insurance companies love it!
I'm sold. This is the 4th product I'll be buying thanks to this show.
My zip board is already on , now for several reasons I've decided to add exterior insulation. The fire rating, using strapping lets me lower my starter strip, the extra insulation and extra water barrier. Rockwood wins because they have incredibly detailed easy to follow instructions, 100 pages for every situation imaginable. I'm not a pro builder so this is incredibly valuable to me to get the job done right.
Products I've bought because of build show, Zip, Cavity slider, and coming soon, Steller flooring and Rockwool.
Great demo of those mineral wool boards. I see a lot of passive house builders using dense packed cellulose in exterior cavities (between the air-sealed plywood siding and the house-wrap). Seems like adding mineral wool on top of that would be ideal, adding fire protection and extra water resistance without compromising outward drying potential.
+Onward to Innisfree that would be an ideal use
Another great video Matt. I bought Roxul insulation to finish my basement from Lowes, the only place I could find that carries it.. The big question is why we haven't replaced fiberglass use with Roxul in US.
This explanation was done very well and sooo helpful!
Good one Matt . . . It is a brilliant material . . . . . Great informative videos . Keep them coming
In the video, it appears the rock wool is NOT exposed, and it is covered with yet some other facing product. No mention about if that facing also fire proof? if not, wouldnt that be a weakness that would need to be addressed to be part of a 'complete solution'?
Hi Matt, great job man, pls make some video showing applying the stucco.
We had an issue with Roxul and the use of masonry veneer. The manufacturer of the masonry anchors wouldn't certify the connectors for buckling for the lateral earthquake forces. Rigid insulation stabilizes/braces the veneer anchors from buckling but you don't get that effect from Roxul since it is softer. If you are using stone veneer, what kind of masonry veneer lateral anchors are you using and are they certified (for seismic/wind forces) with the use of the softer Roxul material.
+Andrew McLellan using a Heckman Pos-I-tie anchor I think I need to shoot a video on that
That would be great. Thanks.
How cool I love this!!
my house is packed with this and I plan on doing the exterior this summer
Should have done the fire resistance demo with an acetylene torch.
Double Dare Fan Why? He said it’s good up two thousand degrees, and an acetylene torch gets over five thousand degrees. Maybe look cool but proves nothing.
I tired to burn/set on fire regular fireberglass insulation with a MAP torch and it would not catch on fire no matter what. I had some scraps from working on my bedrooom and trash can was full so why not :) I dare to say that fiberglass insulation is maybe not fireproof but it's fireresistant?! Anyone want to comment on this?
In Europe it’s called rock wool. It’s extensively used for fire proofing, particularly upgrades in care homes etc.
@@uhighsmith The problem for me was that it was an informal demonstration of something that needs a formal demonstration like one would get in a UL fire test lab. I suspect that the rock wool type insulation would do spectacularly well in that kind of a test but Matt's demo didn't really prove much. I notice somebody below tested it with a MAP gas torch. That seems like a much better test than Matt's because it is much closer to testing the material's resistance to the kind of temperature and heat it might experience in a wild fire or a house engulfed in fire.
Great video! Exactly what I was looking for and wondering about, and I now feel comfortable making a decision to go with Roxul for exterior insulation.
On the "4 things that I really like about this" at 6:40 - maybe one of "fire resistant" and "non-combustable" was intended to be minimal drift in R-value, in part due to the minimal contraction/expansion discussed at 2:50? (That was something I didn't know about and definitely appreciate.)
Matt, another solid informative video, great work and thanks
Matt, traditional stucco systems use a “chicken wire” lath (17 ga or stronger) which is stretched over the side of the house with fasteners. I was wondering, is the synthetic lath ridged? Is it fire proof? Such a lath would transmit any lateral movement of the stucco membrane uniformly and probably result in fewer cracks resulting from minor earthquakes. I love the idea of stucco over Roxul. This totally makes sense especially on the side of a house which is in close proximity (12 feet) to a neighboring home. Provided fire fighters got to your home quickly enough, and there was no severe eve damage, you could be good to go with just another coat of paint over the scorched stucco membrane.
For the reference Matt made, search for ‘Grenfell Tower Disaster’.
That is a really good video. Learned a lot. I would like to try that out sometime.
FYI: Rock-wool or Mineral-wool (brand: Roxul was featured) is NOT a new product and has been out for many years, and now even Home Depot & Lowes carries it.
I've used it on many projects and always had huge success with it.... better R-value, easier to install, fire-proof, water-resistant, and much better sound-dampening properties. It even works great for Tiny Homes and guest homes.
That's right! I started using Roxul (now called Rockwool) when I did my house build in 2011. We also use the comfort board for sound absorbing panels covered with fabric in recording studios. That said, the batts I pulled out of my house where from the 1950s mineral wool batts, so I am assuming this has been around since before the 1950s.
Well planned system install. I used a similar system in 2015 but on a much smaller scale. I noticed this is a pre ON THE BUILD SHOW! sign off. Haha.
I do like that sign off. Nerdy but it’s my thing
Looks a great product. But what is cost over other types of exterior insulation?
Great job, Matt. Keep up the good work.
+He Man thanks! Appreciate the positive comment!
Same insulation they use at the power plants to insulate boilers and duct work.
I've used a acetylene torch on it before and will not burn :)
How do you deal with the window trim interface now that it appear recessed? Also, how would you apply wood siding products? Great video!
Would like to see how you finish the project with installing either siding or stone ESP around the windows that had large gaps in your video.
Great work, love your videos!
If you were to use this along with Tyvek Thermawrap R5.0, would the ROXUL go over or under the Tyvek?
Two years later I will answer the question for you good person of the internet. The ROXUL installs over the house wrap . Best wishes
Matt, love your videos. According to many experts the cause of the London Grenfell fire was not the insulation but the ACM panels because they were made with non-fire rated core which does not meet building code in London or here in the US. Plus they designed with an unusually large air space in the cavity. I like mineral wool. But not all foams perform the same. Polyiso doesn't actually burn it just chars, Extruded will soften and melt at low temps.
The foam in ACM panels *is* insulation.
My understanding was the London fire was Aluminum Composite Panels which is sold in sheets 4mm & 6mm thick, then fabricated into different size panels or shapes (most car dealerships). These do not include any insulation or thermal value. You might be thinking of an insulated metal panel which is insulation sandwiched between 2 exterior metal skins.
After some research I concede you are correct on the ACM. I was thinking of insulated metal panels.
It does turn out there was also highly combustible insulation directly on the wall, so I guess in the end insulation was also a factor ;)
www.fireengineering.com/content/dam/fe/online-articles/documents/2017/Grenfell003.pdf
ROXUL is noncombustible and rated beyond 2300dF upper temp limit. The mineral wool used for thermal and acoustic applications in walls and cavities is light density normally between 2.0-3.0 Pcf and is semirigid. The 8 Pcf material featured in the video is the same material however produced at a much higher density resulting in a rigid product that indeed is much more water repellent compared to low density batts allowing use in exterior applications. Great product and you can run a burner under a section of the mineral wool for hours without any effect nor heat transfer to the opposite side. One point from the video to clarify would be that polyiso foam panels which normally come with foil facers for exterior applications are self-extinguishing when exposed to open flame either to the foil surface or the closed cell foam surface itself. Polyiso also has an R value which is higher than mineral wool or fiberglass that does diminish slightly as the panels age as noted in the video however this occurs only to a minimal degree as the panels lose some of the pentane gas which is introduced in the foaming process and this gas remains trapped within the closed cells for the life of the panel giving the polyiso a higher rate of thermal performance per inch compared to most every other form of thermal insulation. The LTR (long term r value) of closed cell polyiso is published by each manufacturer taking in account the aging of the panel as it sheds a small percentage of pentane adjusting to the surrounding atmospheric pressure for the region where it is situated. When produced R values of polyiso per inch of thickness are commonly stated as high as 7.1 and settle after some weeks to be between 5.8 and 6.2. Once the panel settles to this level it balances and does not continue to lose thermal value, Compared to thermal values between 3.8 to 4.2 max per inch for fiberous insulation products such as f-glass or mineral wool at the same 1" thickness closed cell foams are superior in this regard. Also being closed cell there is no risk of moisture ingress or damage and the foam also provides no form of sustainability for mould or fungus growth.q
Are there any strategies you use to avoid siding wobble from installing in on a soft surface?
Exactly my point too. How do you attach furring strips on too of soft material without creating waves?
This book is a comprehensive guide for anyone who wants to build a second unit on their property. ruclips.net/user/postUgkxzaRUJNcbypw-fRBDbqqz43ULIa-1EGP- It showcases various types of houses, such as garage apartments, with photos, videos, and floor plans. The book provides the square footage and the dimensions of each house, as well as the option to order the plans or customize them according to your preferences. You can choose from a range of styles, from ultra modern to cottages and A frame lake houses. The book also offers suggestions for sheds, pool houses, and office studio buildings. This book is an ideal resource for the aspiring home designer.
Steal a comment, get likes, then try to peddle some garbage later by editing in new scam comment I’m guessing.
Still waiting for your vid on hempcrete :)
That's probably to Green a product for this show if you know what I mean.
Not in Texas. The police would shut you down thinking its marijuana... lol
Great videos as always.
Just one question, how will you be attaching the exrior final facade/siding? Layer of Rockwool is obviously not structurely strong enough. So would you use some super deep and strong fasteners that would go throught rockwool and into the studs? Would love to see the scheme of your wall design.
I believe some are nailing furring strips over the Rockwool.
Great video Matt
I watched this to see what was being applied over the mesh. Like the design! Stopped by another contractors build to speak with a sub and noticed they were using 1/4" Barricade Thermo Brace in lieu of OSB on the exterior?? Is that even sturdy enough on 10' walls to Brace against wind loads???
How is the thick exterior insulation handled around the windows?
Rad. If you switched to a hardi board siding for this assembly, what air gap product would you use on top of the roxul? And how the heck would you fasten down the siding?
Hardie plank is nasty low budget stuff.
I have a CMU concrete block house. can I fur exterior walls, 1 1/2 inch rockwool, sheathing, house wrap?
Love your videos! watch them frequently.
That's not even "scorched" that's just black soot from the flame. 🙂👍
I'm curious how the stucco will go. It seems like you could just push on the stucco and have some flex... Also curious how you might do siding over this? Maybe some z-channels?
+Matt Metcalf Matt, great question. We are doing a traditional 3coat stucco with this synthetic Lath system underneath. It's should be very rigid. Think vertical sidewalks or sheet Hardie. I think a video on this might be a good idea
Having an older house of my own I'm curious of the proper installation for lap siding over this. It's be a great retro fit for a 2x4 framed home.
Agreed that would be a good video.
People forget stucco is basically concrete.
david miller that was exactly what I'm thinking. I currently relocating to a small town and in taking over the care of three older homes that are all shiplap siding. More than that is I'm actually looking at a seventy-five-year-old home with hardwood siding. This home needs a major remodel. This would include two small additions.
Thanks Matt very helpful as usual
I would love to see someone try roxul, with tyvek on the face and just siding over it, or whatever you would put under the siding.
You'll only need 3 inch screws sheet metal screws. Have fun with that build.
I'm starting to think about this for external and internal on an ICF home.
Your video title is Rockwool Exterior Insulation vs Rigid Foam however you didn't say anything about the rigid foam insulation but god information about the Rockwool insulation.
Comfortboard is significantly more expensive than rigid foam sheathing. Additionally, some sources claim it is dangerous to health. A video report of a comparison of fire resistance suggests that wet-blown cellulose in the wall bays is comparable to mineral fiber batting.
Wow, SO relevant for us in California right now!!!
My husband said, lets do this!
Putting this blanket on the outside of the house, the holy grail is insulation that is fireproofed. I wonder if exterior insulation can be implemented with airkrete. And how feasible it is with the current installation methods they offer.
ruclips.net/video/4IQdPmJsrcc/видео.html
Alejandro Maldonado concrete is not water proof. Is Airkrete waterproof?
Did u cover in later vid how the trim detail and fur out is sealed to the recessed windows? I know u said this house will get lower stone veneer and upper stucco so maybe not to much trim detail was in the design. Either way a link would be appreciated. Keep the great info coming Matt!
Great video, but I have even more questions now! My house exterior is a mess. It is aging 3-coat stucco that had been painted (badly) and there is no wood sheathing -- just celotex (spelling?) fiberboard then the stucco. Is there any reason that the exterior couldn't be replaced with first putting rockwool bats inside the wall cavity to replace the old probably-droopy fiberglass bats, then rigid rockwool as both sheathing and insulation, then finish with a one-coat stucco? (no membrane, no wood sheathing) The first contractor I spoke to wanted to put the foam board (the exact brand that was on that apartment building in England!), then a wrap, then 3 coat stucco. Listening to him, I felt like I'd be jumping from one frying pan into another at the very least or worse -- jumping from the frying pan into the fire (perhaps literally).
I have two pallets of the 2" R8 next to my house getting ready for the reno which includes new windows and resheathing the entire house due to no WB installed when it was originally built, going with a peel&stick product.. need a few more items before I begin
The air gap materials are really interesting, I was/am planing on doing a rainscreen w/ furring strips of wood or maybe corrugated plastic (must be UV resistant as there will be exposure from an air gap in the siding, similar to the Ipe setup)
+Chris Anderson sounds like a great Remodel Chris, you doing the work yourself?
Yes, as much as I can by myself. May need help from a friend for the new windows (due to high traffic) are sound dampening ( 45 STC ) and are basically two windows in one (Milgard QuietLine) and thus very heavy.
Price? Also, we have discovered that our house was framed with 2x4 instead of 2x6. What do you think about using it as insulation between the studs?
Planning my new build… what are the envelope layers to add, in order from OSB out? I plan to keep the 2x4s and copper spiral ductwork exposed on interior.
I am going to use rockwool as the envelope, but I need to keep costs down (no stone exterior)…………….
Recommendations are appreciated.
Roxul - Rockwool is what I've looked into. [same] - Soon, i hope, to find a person to build Gabled Roof Frame over back room to meet original house's. [replaces rotted flat roof] Question - I was Wondering HOW to Place it Against the Inside of Lap Wood Siding of back room ['60's] & Attic [1920's] Walls. Nothing had ever been placed there (Fla. House) - Roaches Crawl in, Not willing to crawl out. =6
What is Needed Against Wood BEFORE Rockwool? Thanks much! ~ just wish my brain Knew Long ago. [books then lacked this]
Learned last week, from you, about ability of Back of Wood to Dry out - hence - Nothing, I noted that blown insulation - now in outer walls, [28 yrs ago], I think has caused Paint to pop off in areas. [not to mention it's Over Active Knob n Tube Wire, a no no later learned] =|
When you eliminate a second layer of insulation, exposing the seams, don't the seams leak heat? Have you tested the exposed seams with an ir camera?
Kind of itchy if you get it on your skin I used to work in a rock wall plant in Tacoma Washington.
Sounds great I just don't understand are all the windows inset now since you have 2'' of insulation plus whatever your using for your siding?
Matt, on a build if you're putting 1.5 or 2" of comfort board on the outside would it matter much if you used batt or blown in fiberglass between the studs. Or does it still make a big difference having the better insulation between the studs. zone 4 southern Vancouver Island. Thanks.
Hi, great explanation & demonstration! Thank you! :) For a 45 yr old manufactured home in Nor-Cal (Sierra Foothills) how much Roxul would you suggest using & where? I want to remove the panels inside and replace with either thinner plywood, bead board, or thinner drywall.
Just a thought. On the exterior you do the waterproof plastic barrier, rockwool, perforated radiant barrier then siding... Any issues with this?
I Have an old house with leaky (air and moisture) board and batten siding and no house wrap. I have exposed some of the exterior walls from the inside and am considering insulating. Concerned about mould and rot, could this product be used in the wall cavities and allow for the board and batten and studs to breathe and dry out if they get wet?
lol. I like how you use a tiny lighter to prove its flame resistance.
Having said that, I do like this type of insulation... I'm more familiar with the cavity type insulation, but still looks interesting.
Question I have is , the delta drainage plain... how fire resistant is it ? Is it also a special type to go over this type of insulation? Does the type of drainage material even matter ?
Love your build with the lvl's on this house . 👍👍
+Argo Tungsten yeah the lighter was lame visually. Needed a butane torch.
i'm considering external insulation for my detached house in UK. Its a timber frame house with single skin brick. Not much space for internal insulation. The only thing I don't like is that it will leave the window recesses really deep.
What's the window casing look like on this? Love the rockwool I put in my garage and basement.
Curious if you used it on the roof as well. Are you also adding insulation to the wall cavity as well? If so, what are you using? I am going to build a metal building workshop in liberty hill tx that has z-girts horizontally at 4' spacing. Is this rigid enough to be applied with only being attached at ends and middle? Will be covered by metal corrogated panel. I have Been considering whether I need the advantech sheathing since the bracing will be steel cable integral to steel frame. Looking forward to the answers to all of the questions in this discussion thread. Love your videos.
+Simeon Kessler my recommendation would be closed cell foam and skip the sheathing. That will add a ton a lateral shear, add water resistance, and provide great insulation and air/vapor impermanence
Matt Risinger. Since my land is full of live oaks I was thinking that having a layer of the roxul 80 would give me some protection against fire should a grass fire ever sweep through. I was planning on spraying a few inches of closed cell foam behind the layer of roxul to encapsulate the steel to prevent weeping from condensation, and give me air seal. Plus that creates a separation between the steel siding and the spray foam. Not sure what I should do for the roof assembly. It seems like decking with a peel and stick would provide a secondary drainage plane for when there is condensation on the backside of the standing seam metal roof. Have read on several forums that they recommend not decking the roof for metal but that seems like a gamble since all roofs leak.
AdvanTech on the walls is a great idea. My concern is if the rockwool gets wet somewhere how long would it take to dry being 2" thick and would you know if it was wet? This would not be a concern if the overhang was around 4' or so but builders don't want to make a proper overhang. I think closed cell spray foam on exterior walls over vertical galvanized metal channel to hold siding would be the best thing but haven't seen that anywhere yet! Closed cell foam does not break down and seals out moisture and prevents condensation because air can't get to the surface. Outside is the best place for foam and inside sounds like the best place for Roxul.
Another thing i should have added is spray foam has E84 fire retardant and is much better at keeping your house from burning because the fire can't get to the pine. Sorry but it looks to me like your lying about things here to sell your product.
Pete Bennington Water isn’t a problem for Roxul. It’s naturally water resistant.
Pete Bennington Roxul is non combustible.
Matt
I am a Police Officer in VA. and I am remodeling a 1942 House in WV and was wondering if there is a way for me to air seal the 1X sheeting on the old part of the house with out braking the bank. I am trying to pay as I go
Fair question: How flammable is Zip-R3? How easily does it burn? It seals better than this solution, but at the expense of flamability?
Where do you source comfort board 80 from? I'm in the Austin area and having a difficult time finding a supplier that doesn't have a 3 month lead time.
I’m a fan of Roxul, I installed it in a large portion of my house during a reno. But now my cell phone reception in that area is awful. Awful like can’t be in that part of the house on my cell phone because I’ll drop the call. Thoughts?
Matt, I just watched a video of the 5 worst things builders can do in the South and one was using Stucco. Why would you then use Stucco on this custom-built home?
Who manufactures the "green" layer under the mason-stucco layer is applied? I think you said "Borrell" or similar synthetic Lath system manufacture but the link seems to be missing. I'm in Scottsdale, Arizona. Temps reach 120degrees in summer. Dying to replace all my stucco. Also looking for info on J-joints and bug screen updates if needed where the wall meets the foundation. Thanks ahead of time! Great videos!
Great video, however if its so great why didn't you use it for your roof ?
Why did you use Advantech and not Zip? Was there some benefit in this case to using a separate WRB wrap?
Getting ready to build a 3400 sq ft house in the South. Is the cost of going to this extreme translate into savings on heating and cooling my house?
Can u find out about possible silica problems? Or why there is no risk of silica? Made from rock brings to mind rock dust and silicosis since I work and deal with rock dust exposure. Thx!
Can I use rockwoll curtain wall insulation (5") on the outside of my house wall, covered with 7/16 Zip (R12). Thanks
Is it possible to renovate an existing stucco home with this stuff? Would the existing stucco need to be knocked off first and what if the house only has small eaves? Would the eaves need to be extended?
So the rockwool goes to a couple inches from the window? And the window is surrounded with some sort of exterior build out so you have a nailer for sheathing? I dont see that happening. Wouldnt it make sense if the window flanges were attached to the mentioned frame.. and extension jambs installed?
the firm I work at spec rockwool all the time for the walls though we do tend to stick with polyiso for the roof due to its high R-value and weight. Our projects are all in the arctic and subarctic so we have very thick exterior insulation for walls and roofs... but I do wonder which approach is really best if we need to do multiple layers for either product (Matt mentioned rockwool being beneficial as you can use just 1 layer of 2"... maybe that works in the states but in Canada we are dealing with colder temperatures in most cities... and, again, the projects we work on are in the coldest places in the country). If anyone had any insight on this - if you're a builder or perhaps know of how these insulations perform over 20+ years... would be great to hear what you have to say!
Interesting. Polyiso seems a poor choice for cold climates. www.greenbuildingadvisor.com/article/cold-weather-performance-of-polyisocyanurate
Wonder how the stucco is holding up with all those huge thermal break fasteners
If you are retrofitting external insulation, what can you do to ensure that you can replace soffits in the future and should you extend the apex of the house
I like what i see.
Would you put two layer on the outside to double the insulation?
Where can I find info on this that really lays out the details? For example, if it's 70F inside with 45%RH, and it's -10F outside, if you have R8 around the outside over an OSB sheathing and you're using drywall inside, what is the temp of the inside surface of the insulation and would it be below the dew point? What if you use this in addition to insulation in the wall? After all, R8 is not a lot. I hear people talking about it but nobody really touches on the actual science.
R8 is not a lot in colder climates, in Texas weather its probably descent. In Sweden where I live rockwool as we call it have been very common for decades. Both in the external type as shown in the video (it is far newer however) and the batt type inside the framing.
The position of the dew point will vary greatly dependant on weather and quantity and type of insulation used in conjunction with the external sheets, in sweden moisture barriers are usually placed at ~1/3 of wall thickness measured from the inside. Often in a configuration of 2 layers of batt insulation with the vapour barrier in between the layers, and a 3 layer behind the siding.
Dew point matters less--a lot less than in rigid foam--in Rockwool because it is vapor permeable, as it can dry externally in the spring, summer and fall. If you're -10 outside, you're probably in zone 6 or 7. See this article, which will give you the R-value you need to hit based on your climate zone: www.greenbuildingadvisor.com/article/calculating-the-minimum-thickness-of-rigid-foam-sheathing
nice looking stuff ... Thanks
Is there such thing as to thick with rockwool? Lets say you double up or even triple u the layer? Would 4" or 6" or rockwool exterior insulation be to much?
you would just need some mondo-long fasteners to get from your cladding through the Rockwool into studs/whatnot. Longer the fastener, more $$$
R-value of 8 is insufficient to replace the need for interior cavity insulation. If my goal is to only exterior insulate and replace the need to insulate interior cavities, would I need to step it up to Comfort-Board 110, and if so, what is the R-value for Comfort-Board 110 (their website unfortunately does not list this). I'm in climate zone 3 where the minimum wall R-value is 13.