Exterior Insulation - What NOT to do! (And the Correct Way)

the build show today is all about exterior insulation we're gonna take a deep dive into exterior insulation why you need it the science behind why you need it how to install it and some benefits of rock walls specifically now today's video is sponsored by rock wall but most of what you're gonna learn today from the science and the install could be applied to all kinds of building types in all times of insulation types so first off why rock wall you know there's three big advantages and I've got three visuals to show that I think really show off the big benefits of rock wall number one fire resistance this is your basic butane torch like you're gonna be lighting up your creme brulee and check that out that flame right on that rock wall it looks red-hot but I got nothing happening it is not burning it is not catching fire do that with any other types of insulation on the job and you're gonna find a very very different result that is pretty cool okay so fire resistance number one number two it has some water repellency as well or it's high hydro it's hydrophobic that's what I'm looking for check this out we drop our water on there the cow just beads up and runs off like water on a duck's back that is pretty cool the third thing which is especially important if you're in the cold climates is that it is vapor permeable as well now this is a display that they show often at trade shows but I'm gonna demonstrate here with my home steamer this is what I use to steam my clothes at the house and it generates a fair amount of steam if you put that steamer right up on this rock wool comfort board this is made for exterior insulation a couple seconds later you're actually going to see it penetrate and go through the other side which means that it is vapor open and that is a big deal in the cold climates we want to be able to drive through our exterior insulation and that Rock will does it okay so for part of this demo I'm gonna actually show you some of my screen to my iPad because I gave this demonstration at the International Builders Show in a live version and we're kind of doing the YouTube build show version of that so here's a here's a quick story to get to get started when I very first started using exterior insulation the year was 2001 and here's what mattress gear looked like in 2001 this picture was taken at my construction office I had my next telephone I absolutely loved nextel amazing amazing device but of course my I fashioned wasn't fantastic back then I got a call in 2001 from the field or from the office rather saying he met we're getting served on a lawsuit here at the office you got to come in and see what's up so I went out to the job site checked it out and here's the house now we unfortunately don't have a before photo before we ripped it off but how many of you were around building in 2001 there are two big things that happened in 2001 we had the mold crisis the National mold crisis builders are getting sued all over the place for mold issues and we also had the Efus crisis crisis exterior insulating finishing system efis it was basically a system where we would glue on a sheet of eps foam to the outside of the house and then we put a synthetic one coat stucco kind of like a thick latex paint almost look like a thin drywall mud paint there was a fake stucco that would go on top of that now if you zoom into this picture and I can't really do that on my presentation but if you zoom in here and look at this area here on the facade which looks like regular stucco it's in fact not real stucco it is a synthetic stucco now let's zoom in what we did was back then we would take these sheets of EPS foam one inch two inch three inch you could go pretty thick and you'd put a bead of glue on the backside and you'd trowel that down so it was almost as if you were installing tile and you would glue it right on in this case the plywood and then after that we'd coat on that one coat stucco and then we would tenaciously caulk the house for all the penetrations all the windows all the doors all that stuff what's the problem with this system this this system was a face sealed system which means that you had to have the perfect caulking job for the life of the house in order from water not to get behind there and here's what happened when I ripped off the very first one you can see water would weep in at these joints around the windows and doors all those sorts of things then the water would run down it hit this seam and the plywood and kind of gathered there and believe it or not this is a house that was less than a year old that we ripped off the facade and that's how much rot we found in one year can you imagine what this house would look like in a couple years it would get real bad this was the time of my life that I really started delving deep into the term that we now call building science but for me it was just trying to figure out why these buildings were failing and I love this definition but the important thing on it is understanding and preventing building failures that's the biggest part about building science that I care about and most of my builder friends care about because we want to make sure that we're not building houses that become a problem they've become a lawsuit all right so the build showed today three things why are builders moving to exterior insulation what's the comfort board advantage for that and how do you actually practically use it on your job sites now first let's talk about the climate zones in America so America is broken up into basically seven different climate zones and you want to consult this map as to how much insulation on the outside of your house you're gonna need because you're gonna need much less in a hot humid climate than in the very cold climate another big reason why builders are going to exterior insulation frankly is because we're getting forced to do so if you look at this slide here that has the energy codes 2012 to 2015 you're gonna see a big change where you're gonna see this plus sign and a lot of the codes and where you see an R value of a plus sign that means cavity insulation plus exterior insulation so for instance in the 2015 codes climate zone three and up there's an exterior insulation unless you have a thicker cavity insulation so that are twenty and climate zone three here you can do that or you can do our 13 plus five on the outside now you start getting in climate zone six or above you have to do exterior insulation I think this code is going to continue to get stricter and that's also going to end up being for us down here in the hot humid south as well so really no matter where you're building in North America including Canada if you're not already being required to use exterior insulation it's coming soon now yx2 your insulation what benefit does exterior insulation give your house besides of course additional thermal benefits there's a big story from a building science perspective on exterior insulation because it's gonna prevent condensation in your walls now I borrowed the slide from my friends at construction instruction but basically what you're looking here at this on the slide is the temperature of the sheathing in really cold climates in cold weather in the wintertime that kind of December through February timeframe and what it's showing is that with normal cavity installation of our 13 there are some times that you very well could have condensation happening inside your walls and moisture in your house is going to potentially find a cold condensing surface in there now if we add cavity insulation that we're gonna warm up our sheathing which means that we're not going to have as much potential for condensation on the inside so that's a bigger reason why codes have moved to exterior insulation from a durability standpoint not just in an energy efficiency standpoint now let's practically look at how you install it I showed you a few the advantages of the rock wall comfort board earlier when I showed you those three tests but here's something you need to figure out as a builder is how to install it and where to install so first of all this board here this is an r8 board they say it's 2 inches bore two inches and you can get this in two foot by four foot sheets you can also get it in four by eight sheets if you measure it it's actually slightly less than two inches and I actually measure this around inch and 7/8 but they call it a nominal two inches so what happens when you install that on the wall you've got all these penetrations on the wall that you're gonna have to deal with so for instance this brick mold on this exterior door look how much further this comes past the brick mold that's pretty typical on both brick molds for doors and for windows now installing this comfort board is pretty straight for you're gonna use a cap fastener like this this is a great one from Road and house and then you're gonna screw that in with your screw pop that on and that's going to hold that exterior insulation on but one of the things that we have to deal with very early on when we start to think about this is how do we deal with this thickness let's measure this brick mold I'm curious what this brick mold happens to to measure here this brick molds inch and a quarter so if we've got nominal two inch thickness exterior insulation that means I've got roughly three quarters of an inch I've got to deal with where that comfort board is sticking out and that's not even including cladding you know I've got to figure out what to do with my let's say my hearty plant siding or my stuck or whatever is gonna go on the outside so let me show you on my iPad here what we've done in a couple situations so this house right here I just finished this in fact episode or two ago I talked about the HVAC system in this particular house and this is a kind of French country style house that has a mix of both stucco and stone on the outside and this is the very first house that I've ever done where I wasn't doing a more traditional siding with comfort board on the outside so here's what you do or here's a couple options for you now in this particular house we had a mixture of like I said stucco in stone and you'll see on this case we actually put the window installed the window at the sheer level or at the at the sheathing and then we cut the comfort board back by about two inches because the the client wanted a stucco return and didn't want to see any additional kind of moldings or other things that would add thickness so you'll see here on the left we've installed that comfort board and we left that gap in there of about two inches all the way around there now we put a dimple mat on top of that area in the left here this gray dimple mat and then there's a green dimple mat on the right we've got some future episodes where I'll talk some more about those dimple mats but what you're seeing here is the guys are just tacking it up with a couple fasteners now this is before I knew about this plastic face fastener I was actually using metal roofing cap type fasteners but once it's all up you can see the house kind of looks like a bit of a quill until Oh and then again all the green areas are getting stone all the gray areas on this photo are gonna get stuck oh but here's what the cross-section looks like you can see here we've got our vapor permeable membrane that's that first layer right there we really if we're gonna use a vapor permeable exterior insulation like comfort board we want to use a vapor permeable membrane as well this is especially important in those climate zones four or five and above because now we can drive through that then here we've got our two inch comfort board and then beyond that it's gonna be hard to see I'll show you in the next slide I've got that dimpled mat so I can maintain an air gap the dimpled mats right in there and then here's my stone facade on the outside now if you zoom in this is that air gap I was talking about it's about three quarters of an inch and now any moisture that's mitigating through my stone is going to hit that air gap and be able to dry drain and dry out of that cavity now if we're doing stone on a on a larger building this happens to be a school that I visited that was under construction now this house as a fluid applied vapor permeable on the outside and in this case they actually put the masonry ties on first so that they could detail all the fluid applied around those and then you can see they actually stab through the exterior comfort board and then that's where that tie is so this is a two-piece tie this is piece one right here it's kind of l-shaped and they're gonna fasten that into the building and then piece two which is right here comes in and hooks down and that's that's that second piece and that's now going to tie that masonry facade back to the building so that we don't have any failures with that okay now let's look at an older project of mine where I didn't want to use some of those other methods I actually wanted to do more of a contemporary look so here's our windows right here and again we've got about an inch inch and a quarter flange on the side of that window here's our vapor permeable house wrap that was on there and here's what I did I took an elf lashing it's basically a flashing that I got bent locally you could have your roofer do it you could have a metal bending company if you're here in Austin I use a capital company to bend all my sheet metals and this profile is pretty standard it's it's a L shape where you've got a hem on there so let's see if I can draw that so it's L shaped and then we've got a hem coming back like that and then you can see where we installed it on the sill we've cut it flush and then we've installed it on the jamb here we've cut a corner of it and bent it over now when we install that we're gonna put a bead of sealant on there that's just a bead of geocell or some other metal sealant on there but we're not so much worried about waterproofing as we are just giving us a cavity here that's deeper so now when I put my rock will comfort board on this side here you can see I've got a lip that's coming out from the window and in this case we were sticking out about an inch and a half past that window flange so now I've got the depth I need as we run around that whole window sill all we're doing is basically making an exterior jamb extension for the window and here's what it looks like I unfortunately didn't get a shot in progress but now you can see here's our here's our window this is a you know a darker window which is pretty popular these days this metal that I used happen to be paint grit but you could use anything you could try and match the windows if you want it just about anything that's gonna be on your roofers docket is gonna be available for you to bend or your sheetmetal supply house and now you can see where this hardiplank siding dies in or whatever type of siding you've got dying in I still have a gap where I still have a reveal I should say between the siding and this bent metal here so now we've got a reveal between the bent metal and that siding and from this angle it really looks nice and it's like I said it's kind of like an exterior jamb extension I really like that detail this this happens to be on a house I built with Forge Kraft architecture okay so now what if you don't want to do that you want a more traditional look on the outside without that more contempt there are a couple other options you could do and I've done this before when I first started building here in Austin I did a house with this this is an exterior window buck if you look at this photo back here is the let's say 2x4 that the house is framed with this is the sheathing right here and then where the rough opening is we frame this out with an extra 2x4 so right here you've got another 2x4 on the flat the problem with this though is it makes for some serious water proofing origami fairly difficult because this wood of course is not rot resistant we need to make sure that that's thoroughly flashed correctly and we did all kinds of kind of origami to get there another product that I really like that makes this window buck quite a bit easier is actually called thermal buck now this is a product that's made from some high-density foam this must be probably EPS foam and then it basically has some kind of rubber bedliner on the outside you can see they sell it in different thicknesses they've got it in one to three inch actually I'm sure a bunch more sizes than that but here's how here's how it works this is actually John the inventor of the product showing us how to do it one time at a Lunch and Learn we did at my office here in Austin you're gonna cut these pieces on a 45 degree angle so you can picture frame the rough opening and then John's using a specific caulking that's basically gonna it into place he's gonna those miters as well and then you're gonna see that he's basically gonna picture frame that all the way around here so he still has this last piece that's going to get installed right here so that now we've got a picture frame and that window rough opening is brought forward and what that's gonna leave us now is this gap or this lip on the side here and in this case it looks like it's about I don't know two inch lip let's say which would be perfect to slide my comfort board right up against this lip right here and now I've got a flush plane up against my window and my window is gonna get installed right into this book here's a cross section of one they use the different peel-and-stick vapor permeable in this case and now you can see they've slid the comfort board in there and then they're even starting to show what the rain screen battens would look like but look at this thickness right here this is this is what I'm talking about we can go to very very thick 3/4 I'm not even sure how thick they go but very very thick on the thermal bucks so this is this is a good way to go now get a couple project photos to show you this is actually a project that a builder here in Austin did Marco Larsen I'll put a link to him in the description but mark did a great job on this house again he's got a vapor permeable exterior on there and he's using that same thermal buck his he looks like he trained his carpenters to do this his frame carpenters here in Texas most the time our framers are also installing our exterior windows and doors so he's got his guys installing that thermal buck all the way around now you can see that thermal bucks in place and then he's installing a window inside the thermal buck you can see on the inside he's got that thermal buck coming in as well so he's gonna have to try and figure out how to trim that on the inside because now his windows pushed further to the outside he's gonna have a thicker interior jamb when you're a custom builder like I am that's really no big deal the finish carpenter is gonna come in and he's gonna custom cut one by material or poplar material to make a custom interior jamb for these windows pretty simple to deal with now when his rock wall goes up his rockwool and you in this case you can see is about 3/4 shy right here so that now when he puts his rain screen battens on his rain screen battens are actually gonna be flush and I'll show you that I believe on this slide yeah so now right here you can see his rain screen battens are flush with the side of that thermal buck he's got a nice higher performance window in there he's got that full r8 on the whole outside of this building as a continuous thermal break and then he's running his rain screen battens I should probably pause and tell you briefly the benefit of the rain screen battens if you're not familiar with those what these battens do is this is just really a 1 by 4 3 inch thick that's gonna get screwed in with a structural screw like this a nice big bugle head screw and as that gets screwed into the studs now the battens are gonna hang the siding that goes on later and what that benefits how that benefits us is now we've got an air gap behind our cladding we really want that air gap behind our cladding so that any water that's forcing its way in past there is going to hit that air gap and it's gonna run harmlessly down we don't have any capillary action to bring that in and it's gonna bring a lot of drying and drainage to our facades which gives just great durability so anytime we can get an air gap on a project that's definitely gonna be best practice this is my friend Jake Gardner this is a picture I stole from him from Instagram and then asked him if I could use a couple of his pictures very traditional house with a really traditional siding on it again similar details to what you saw before he's got that thermal buck on there his windows are brought out he's got the rockwool on the outside and then he used a really traditional wood siding on there to get a very traditional house and what I love about this photo I think this is actually an addition project is that when it's all done you can't tell you've got this thicker exterior cladding it looks like a very standard house great job by Jake I actually have lost track of which builder I got this from so when I figure that out I'll pin a comment below and tell you this was I'm sorry that I I can't place it right this second but again vapor permeable membrane on the outside tons of exterior insulation this looks at least like it's an r8 here's a tip for you that I like about this photo when you're putting your rain screen battens on you've got some ability to compress that rock wall so what this builders doing here is you see that right there that's a string line he's running a string line across his battens so that now he can wet as he screws that screw into the battens he's using these big structural screws as he screws that in he can tighten it in just right so that it hugs the line he could back it back out if he needs to or he can push it back in see what he's got a nice flat wall plane another tip from this builder I like he's got a traditionally insulated attic on this house meaning that his attic is vented and so when he got up to this gable section he didn't need the extra exterior insulation or rock wool comfort board up there what he did was instead he took the same thickness I think he was probably using let's say inch and a half comfort board and he ran a 2x4 up here and then ran rainscreen battens on top of that so he doesn't have exterior insulation on the gable because it's not necessary he's insulated down here inside the Attic on the flat great job by this builder all right let me close it out here we've talked a lot about the advantages of comfort board we've talked a lot about why we like it how to use it why we're gonna be forced to use it if you're not already but I want to talk to you for a minute about how to sell it you know I've been I've been building really high-performance houses really since about 2001 2002 about 15 years of that on my own as a custom builder and nobody does sales of performance better than the guys at Yeti when I moved to Texas 15 years ago I had a I don't know $40.00 Igloo cooler let's say I don't know if that's the brand but a really cheap cooler the lid would break on it all the time the straps would break all kinds of issues with it and when I needed a new cooler what did I want after seeing the advertisement from these guys and seeing some other people that had one I bought that one right there that thinks gosh probably 12 years old now a giant Yeti cooler and what did I spend in that yeti cooler almost 10x what I spent on my last cooler but you know what I did it happily because it's one that I knew was gonna last but what does Yeti do better than anything else they sell performance I love this ad from Yeti know I've added a few things on there that are my words but basically what do they do fat wall design permafrost insulation we do those things too don't we we're building phat houses houses that have more insulation thickness than a standard house or than a standard code build house and that's really just your thermal control air right by adding that rock will comfort board on the outside of the house you may be doing more than what your competitors are doing you may be doing even more than what code requires but by selling that correctly and telling people about the performance the benefit they're gonna have to their energy bills the benefit they're gonna have to a long term durable structure that's built better than most houses I think we can sell that the other piece that I like about Yeti is they talk about their interlock the lid system it's basically a gasket there they're selling air sealing and behind thermal air ceilings the next step in the process guys I'll leave you with this quote from my friend Steve basic we can sell better houses we can build better houses but we have to know the process and like I showed you at the beginning we need to know the science behind it before we do it so hopefully you learned something from today's deep dive into rock walls comfort board big thanks to the rock wall guys for sponsoring this video and sponsoring the build show for the last couple years they've been a great partner in the business if you're not currently subscriber hit that subscribe button below we've got new content every Tuesday and every Friday otherwise false on Twitter Instagram otherwise I'll see you next time on the build show [Music]

Channel: Matt Risinger

Views: 563,920

Keywords: The Build Show, Matt Risinger, Insulation, The Build Show Insulation, Rockwool, Rockwool Insulation, Insulation Best Practices, Exterior Insulation, Exterior, Remodel, Remodeling, Build, Construction, Building Science, Home Building, energy efficiency, r value, how to, comfortboard, mineral wool insulation, mineral wool insulation installation, mineral wool soundproofing

Id: E2Gmr-D1kDE

Length: 25min 59sec (1559 seconds)

Published: Tue Jul 02 2019