The Perfect Wall - Building Science Training

alright guys in the build show today I get a special one for you we're going long so buckle up I'm going to tell you the full story on my house under construction we're gonna get into some nerdy building science talking about how you could build a house that would actually last 500 years and we're gonna talk a little bit about a passive house certification we got some really interesting stuff now we're actually filming this build show for my local chapter of the American Institute of Architects and I have my architect with me so this is going to be kind of a different episode the original intended audience here is really architects in Austin Texas where I work but I thought you guys would enjoy this too today's build show all about my house let's get going [Music] I've got with me the architect in the project you all know kit Johnson Christopher kit Johnson architects hey kid thanks for joining me man I appreciate it watch me once you throw that mask in your pocket so it's not a hanging off all day we're gonna attract it we're gonna keep our distance as we're talking so the purpose of today's meeting is of course to give you a tour of the house but this is a kind of a special and unique house it's actually my family's personal home but it didn't start that way we've kind of evolved a little bit we're also have some pretty unique building science details going on here we followed Joe Steve Rex perfect wall concept on this house and as kind of a result of really going for a super efficient build we've realized that it would be wise to pursue Passivhaus certification so on this video we're going to give you a tour we're gonna talk to you about the project we're going to talk to you about perfect wall and kind of teach you some of those concepts from Joe stearic at building Science Corporation and we're gonna talk a little bit about passive else institute us how this house fits and why you might consider doing your projects in the future to that standard but first kit why don't you give us for those of you who don't know anything about the project kind of an intro on how we met and how we got started on this project well not I don't know if you remember this but it was actually at one of these crannies that's right this is pretty Cove in nineteen but you know we were just chat and then you said you know hey I bought the house right across the street you know I'm thinking about kind of just experimenting with it would you be interested in kind of working out a few details for me I'm just thinking spruce it up you know I'm gonna put a lot of money into it I'm just gonna be really yeah it was it was really low and yes yeah should be kind of interesting I like some of the details that you do on your houses and so I thought just another reason why builders and architects need to mingle at creating me yeah alright demarkation ships yeah get your marketing down yeah it's amazing to think that's where we started yeah and what we're about to walk through today so a little background on the project we're in 1970s neighborhood I've actually lived basically right across the street for the last thirteen fourteen years I know this neighborhood I love it this was a house that was owned by a neighbor who had been divorced and was getting ready to retire the house was in terrible really pretty dilapidated shape but when I approach kid I said you know let's do a smallish remodel I want to spend maybe 50 grand I want to turn this into a nice project but I don't want to go over the top I think it'll be a family rental house that sort of thing maybe my parents had come back and spent a month or two in the winter because they live back east has that developed the more and more we talked about it with my wife and I we said you know this this would be awesome why don't we move into this house and then it was a bigger remodel let's transition a little bit as we with that as the background hiring kid and saying it's a small remodel if you guys haven't seen my videos I do videos on all kinds of different things but I really focus on efficiency and durability how to build a better house I've really tried to focus on building a better house each time I build so for years now I've researched all these different methods for building I've seen all kinds of different building products but the one concept that I always come back to that I think is really an interesting concept and and can radically change the way we build America is Josie bricks perfect wall concept I'll put a I'll put a link out so you guys can see that it's a you know just a couple page paper I read maybe 10 years ago and it's taken me years to kind of understand it fully we did a house a couple years ago with rouser architecture where we use those principles and it got on the cover of fine home building and so I wanted to use those principles but do it in a way that would be maybe a little bit more of a family house oriented way a more normal looking house and kit with that as the background why don't you tell us a little bit about the kind of architecture you're seeing here today how it fits within the neighborhood how people are gonna perceive the house when it's all done yeah I mean well you know from the outset we it was just really it started off just to be a little spruce up you know definitely we're in a 1970s neighborhood kind of low-slung mostly single stories certainly nothing higher than a two-story house none of the tower houses you see in Central Austin so we wanted to keep up with that didn't want to be the obnoxious architectural house in the neighborhood these are all hats friends and neighbors and he loves them and he doesn't want to be that guy yeah and so he came to me he's like okay how do we spruce this up so the initial ideas when we first looked at it were just some little doodads and you can go back and see the early episode and so we haven't lost track of that we've wanted to still you know spruce it up but without you know trying to make it garish and obnoxious in the neighborhood so with that you know we've really kept the same massing now one thing we did was we raised the pitch on the two-story volume and then we actually lowered the pitch on the single-story and that's where we have our pop up and that that's kind of the pizzazz and we'll see that when we walk around the house but for the most part it still says quiet it stays quiet pretty subdued house yeah and we wanted it to really fit within the neighborhood so then with that as the as the background let's get back to the perfect wall concept Giusti brick has this this paper about perfect wall where he says you know we could probably build a house out of standard materials things like two by fours and standard construction but that house could last 500 years and when I read that I thought you know this is this is a concept but we're not used to in America I've been to England before and I stayed in the English cottage that was built in the 1300s and you know growing up in the East Coast I'm used to seeing houses that were 100 maybe 150 200 years old the 500 that's crazy that's really super rare and obviously our country's not that old but in Europe that's pretty typical it's pretty common to see houses that are 100 200 300 years old so how do we do that you know we're talking about wood wood is an incredible building material God's designed something that grows that's sustainable that sequester's carbon that's easy for us as carpenters to build with but what does would need to be to be lasting and durable it needs to be dry right your dining room table that you got 20 years ago is still in great shape right it's in your dining room it's in the air-conditioned envelope of your house it's not getting wet if you spilled some water on it accidentally you wipe it up and it dries and it's fine what if we treated our houses the same way as we did our dining room tables what if we put all of our control layers on the outside in a way that would control what other control layers by the way we've got heat air vapor and thermal right we've got let's start with water number one liquid water our houses need to control water if water gets in on a modern house with insulation and with modern codes it's not gonna be able to dry houses that were built a hundred years ago a new insulation you know when we remodel those houses there's still some of those in Austin they got wet they dry they got wet and dried no problem a modern house built to today's standards if it gets wet it's not gonna drive the next thing we need to control is vapor we need that vapor control on houses we'll come back to that in a second air control is also vitally important because when air flows through houses through leaks through cracks it brings with it moisture and in our Texas climate in particular where it's hot and humid outside you know it's not super hot right now it's probably 70s but it's real humid I'm sweating and if you were to bring a cold glass of water outside you would see sweat gathering on that when air leaks in it's bringing moisture with it that can condense in our houses and that's gonna cause problems and then the last control air for our houses is thermal that's our insulation layer what's the best place for that insulation should we be stuffing that in between our stud cavities or should we put a bunch of that insulation on the outside of the house and this is kind of the genesis of perfect WOD I'd highly encourage you to read the paper but we're using a lot of those concepts where we've got continuous control layers from the foundation from the slab of this house all the way up to the peak of the roof continuous without any breaks and that's really what we're gonna show here let's walk up to the house kid and we can talk about a couple of those layers I do want to say that we had another architect involved in this project as well and out-of-town architect friend of mine named Steve basic who's based out of Boston Steve did an incredible job of working with kit and I kit did the heavy lifting on the architecture and the permits and the floor plan really all the details for the siding and all that sort of thing but all these details that are kind of behind the scenes in a hidden this is where Steve helped me out tremendously and did a great job any kid he's fantastic he was a big brother he's a big brother that's right so what you're seeing here is we've got two inches of exterior insulation you can use all kinds of different products and I have over the years I ended up using foil faced Paulie ISO on the outside of the house this is two inches and what you're seeing on the outside of the house is that it's running from foundation all the way to the peak of the house and it's a little hard to tell here but if you look at the side of the house you can start to get a feel for what's happened here see how there's two layers on the roof right there and then you've got these two by fours right here they're kind of above the insulation what we did was we frame this house with a term that I'm I just pulled out of the hair called Monopoly framing in other words when we framed the house first we framed it without any overhangs the the green Huber's zip sheathing you're seeing on here goes straight up the wall and then transitions right to the roof we cut the rafters at the wall line and ran the sheathing up and so there was no overhangs it looked like a very modern monopoly house let's say the idea was then we could run our wall insulation all the way up without a break and then transition to the roof and you can kind of see that here see we've framed a flat soffit right here but we framed it after the insulation and this this happens to be our kind of garage edition but if you pop in over here you can see what's happening in the garage where these rafters in the garage were framed after the wall insulation was put on so we we framed the walls this this floor joists were here we framed the walls on top just traditional platform framing and then we bolted on that ledger you see right there that's a I'm gonna a 2 by 8 or 2 by 10 lvl ledger and we bolted that on with some real long bolts a zorse pax power lags basically a modern lag screw that's lagged all the way through the foam back into the lvl beam that's back there so now even this roof isn't breaking my thermal layer and as we walk around to the front door you can see the same thing happening here for this porch roof the frame carpenters put all that insulation up and then framed the roof on top of that so all the overhangs happen in the same manner here including the overhangs from the main house so if we look up here you can you can see we've got these 2x4 lvls that are sticking out as rafter tails those aren't the rafters to the roof those are a fake tail now of course those are going to be hidden we're gonna use some James Hardy products on the outside to get a mixture of both brick and Hardy on the outside of the house but those are giving the structure so we could make an over roof I've found over the years all the rot all the mold all the problems with houses typically happens in the lower section of the house you know those those gutters got removed or got overflowed the water runs off the roof it splashes back and so we're really taking care and attention for that bottom one to two feet but that umbrella over the house that big overhang I've got a two-foot overhang basically everywhere in the whole house is giving us a huge measure of extra durability it's also giving us a little bit of a Sun umbrella right texan's a hundred years ago wore big cowboy hats and the big cowboy hats served a purpose even in the hot days to keep the sun's rays off of us so having a cowboy hat on your house makes a lot of sense in our Texas climate kit let's transition to you we talked about perfect wall a little bit that's that concept of those continuous control layers all the way from the foundation to the ridge let's meet you inside we'll talk floor plan alright so Matt's been talking a lot about the details you know Steve bricks perfect wall house and all that which is all good but it might be good just to reverse a little bit just to talk about the big ideas and this is our architect audience so you know with the house once Matt decided like you know what we're not just gonna spruce up the outside we're gonna really tackle this thing and we're gonna do it right and so in getting into it you know some of the big driving ideas were light just bring in a bunch more light this is a typical 1970s house you've got all the light on one side of the house and it's totally not balanced by other any other openings in the house so that was a huge driving idea another idea was like more space just clean it up you know before when the house when Matt purchased it there was a huge stairway here the kitchen was tucked all the way back over here on the west side of the house and then we had our living room over here so one thing that came out real clear in the early design process was like hey can we just get rid of that stair cuz that's the thing that's messing everything up because we were talking about ideas about like how do you look around the stair and and connect the kitchen to the great room so got rid of the stair the stair is going to be finished out over here against this wall and we'll go into that in a second but that completely changed everything another thing that changed everything up was Matt again tried to stick with you know work with what he had the bones with what he had but it didn't take him long I mean gosh II had just gotten into demolition when you know just looked at all the the mold and water damage and Matt made the calls like hey I'm just turning it down to the slab so everything came all the way down to this slab when we have these beautiful lvl studs in here by the way yeah yeah huge donation by the way I got I got a bunch of a bunch of that donated it's such an amazing position I mean that people are wanting to give me some things for my house yeah not everybody gets that I admit but beautiful I've never liked salivated over studs before beautiful studs but going to 9-foot right wasn't that huge huge I mean it was amazing that one foot I mean again typical 1970s house we got that eight-foot ceiling it wasn't so bad when the house was chopped up so much but you know now that we've opened it up in the kitchen was what was big scare once we you know got all this opened up and we looked at what the kitchen was at eight feet sian this is a pancake house you know it's terrible so raise it up to nine feet made all the difference and if I could pop in there real quick I haven't talked about passive else yet I'm gonna talk about that in a minute but one of the driving factors on that height for me was I really over the years have wanted to do slab insulation the first time ever did actually was on Scott Ginn durs house if you know him from forge craft Scott and I build a house together for his personal family I don't know seven eight years ago built some really high performance things and that was my first insulated slab edge we insulated the outside of slab the details were hard on that it wasn't easy to get an insulated slab but I see the benefit of it because this slab in the wintertime draws a lot of heat out of the building so in working with Steve basic Steve has a detail that I had seen before in the Northeast where they basically pour a standard slab and then you insulate on top of the slab and then add new subfloor and that's we're gonna be doing here I'm going to add an inch and a half of rigid insulation on top this existing 1970s lab I'm so thankful that I'm basically on rock out here this lab hasn't changed at all since that was poured in the 70s so we're gonna add an inch and a half of insulation and then on top of that I'm gonna do a floating subfloor detail we're gonna use three quarter inch Huber Advantech subfloor we're gonna do two layers that are glued and screwed together that's gonna float over top of that it sounds crazy but it actually works I've been in houses like this in Boston have been built with that method so that now I don't have any weirdo details there's no termite issues and none of that all I have to do is is put that insulation down and put that subfloor on top now I've got this huge thermal break on top of my slab big big deal now basically in my house has insulation on the bottom up the sides and all the way up the roof continuous we're going to talk about passive else in a minute but that extra three inches on top of the slab made a big difference in my ceiling height decision and ultimately deciding to tear the house down and get and start new it just wasn't enough salvage value and there's so much rat issues and rot and mold and all kinds of stuff on the 70s house that have made it kit talked to me about what you did in terms of changing this layout to work with my family and and also talk to me a little bit about the second floor and then we can walk up there yeah so well just again just back down here the whole big idea more light and so once we open this up the other thing we can do we did was also open up the front here and so now we've literally got it's glazed in but it's essentially a dogtrot house aesthetically at least it's letting the light through so we've got that that's opening up and now our lights you know much more balanced we got the big kitchen you know that's got four kids they're all growing a lot big family kitchen now that we've got we've actually pulled we took a little bit of space from the garage and so made the kitchen really sized for modern kitchen yeah and so that that was a big change but the big thing here is just got rid of a lot of the rooms and now we have the great room with now the backdrop is either you're looking out onto the backyard or we've got this beautiful stair that's going to be coming in here this will be fully detailed out and then what we're going to do is we're going to tuck away you know they a lot of homeschooling and so we've got little little pockets all around the house for the kids to study and so underneath the stair here we're gonna have you know a hidden door that's gonna hide a little work area underneath the stair but this will be a beautiful backdrop to the great room here yeah we're gonna use a fair amount of wood on the inside too kit and I are working with Kim trust on the interior design and we've got a plan for some wood ceilings in here and then some wood along this wall and some wood into the pop-up which by the way have we talked it you've mentioned that earlier talking about this pop-up cake is that everyone who comes in here yeah mentions that and I love this detail oh the pop-up makes it you know it came from necessity we may move the stair from over there to here we had to do something to be able to provide the head height to give us the space to get up there but when you're doing that it's just an opportunity for to bring some light in and so rather than have you know more skylights you know we've got the six windows up here that are letting light in we've got it on both sides and if centrally it's just this big light well that's gonna completely light up the interior here bounces off the white wall and the great room now has all the light that Christy wanted that's what I heard from the very beginning was like more like more like every time I talk to Christy is more light and so this is definitely gonna bring all the light that she's looking yeah it's been awesome before we transition to the upstairs kit let me let me talk a little bit about this wall over here because you can see the backside of the sheathing here this is zip system sheathing we use on the outside which is that green or brown system that uses tape on the outside I've used a lot of different systems over the years but one of the benefits of zip system and all the peeling sticks that you've seen me use is that you not only get really good waterproofing but you get really good air tightness and we're going to talk about passive else in a minute but regardless about regardless of whether you're going for a passive house rating having a very airtight house is critical especially for us in Texas we need to take control of the airflow and not let our houses breathe everyone always comments on my youtube videos when I talk about air tightness all these houses are too tight you're gonna kill people they need to breathe you and I need to breathe our houses need to be tight if we don't build a tight house if air can leak in under the bottom plates around windows around outlets and doors and that sort of thing when that air leaks in especially in Texas it's bringing pollen and about you but I have cedar fever and cedar allergies it's bringing all the mold that's in the air in a lot of days the mold count in Texas is crazy high it's also bringing humidity in the house and regardless of that it's bringing the outside temperature in and we're spending money to air-condition our houses or to heat our houses we don't want that air to come in just any time the wind blows we want to get the tightest envelope we possibly can and then we want to install a fresh air system that will bring air in funny timing with the wind blowing to bring air in on our terms when we want it to come in right I didn't want that air to blow in right then but I need a continuous puff of fresh filtered dehumidified air in my Texas home you need that wherever you are in the world whether you're in Minnesota or whether you're and the tip of the Florida Keys we want that air to come in in our terms so what we did with that monopoly framing was we framed the house with this these walls that went right into the roof line we taped everything with zip system to sheathing tape that's that tape that goes on there and then we did some really good air sealing details where the bottom plate hit the concrete and also where the sheathing hit the concrete in the outside so we've got a very tight envelope on the outside of the house now we could have done that as I said with a peel-and-stick product I've used a lot of poly walls Illuma flash that's a great waterproofing and air sealing product for the south I've also used a lot of the Casal Dorkin products with some German products those are very vapor permeable and those work great too they're also very air tight this is a product I thought was an interesting choice too we decided because this wall is between my garage and my house I was only going to be able to put bat insulation in here and the whole rest of the house as you saw has are 13 continuous insulation and my garage I was trying to figure out how do I get air tightness and I want a thermal break I want some insulation there so I ended up doing this inch and a half our system sheathing this is our six point six so it's about half of what my other walls are but it's gonna be pretty tempered in that garage compared to the outside walls and I see that again with that same zip system she thinks oh I could tape it all and then we're gonna do some tape details between this and the concrete slab and then we'll also have to air seal with some more zip system sheathing that sealing line in my garage later so that my house stops here and my garage is thoroughly sealed off another big thing that's really important detail wise is we're talking about air tightness is anywhere we penetrate this envelope for instance see how my my wall stops right there and then I've got these joists that continue on I block those joists off ahead of time before my mechanical start and it's critical to tell your HVAC guy your plumber and your electrician for every hole you drilled you can only put one thing in that hole one wire one pipe one whatever if it's going to the outside of my envelope so where my pipes Penance right here I don't want one big hole with several pipes going through I just want one small hole with one pipe going through so that I can detail that for air tightness I'll probably end up coming back in using some spray foam in this one particular spot that's a very tricky spot but I don't need to rely on spray foam really anywhere else for the house for air tightness all my air tightness is on the outside now I mentioned earlier that perfect wall concept in the past that house that I did a few years ago with Eric arouser we did nothing but outside insulation on this house I'm doing a mix I wanted this to be a little more kind of normal so to speak so we did two inches in the walls four inches in the roof my walls on the outside are about our 13 and we're a little shy of our 26 on the roof and then on the walls I'll be able to come in and use batt insulation I'll probably use rockwool kind of like what you're seeing in the ceiling line here on these walls because I don't need to worry about air tightness I don't need spray foam for some air tightness benefit and over the years when I've done nothing but spray foamed houses I'm always a little bit disappointed with the blower door results so what we're doing here is we're not relying on any of that what we're doing is sealing everything on the outside kid anything I missed as I was talking about some of those details I think you got it I don't think it's just good for the audience to hear I mean it's just really thinking those through and it's not just from what you need to tell your subs about you know penetrations to the wall it's getting in you know the head of the architect and the architects staff I mean like hey you need to be thinking about this clear delineator between inside and outside not just outside environment but I mean looking at your garage is an outdoor environment with all its pollutants before we go upstairs let me transition for just a second and let me talk to you for a second about passive house principles I'm certainly not an expert I'm not a certified passive house builder yet I will be taking those classes but this is an interesting concept that I've not really talked a whole lot about on the channel even though I've visited several certified houses and been to several houses under construction that we're pursuing certification so passive house if I could boil it down and I'm looking at no it's sorry about that it's basically utilizing a set of design principles to attain a very quantifiable meaning we can we can say the number we can calculate the numbers but also a very rigorous and testable level of energy efficiency meaning you know thermal efficiency and also air tightness for a house and these are my words not passive aus institude but so it could passively survive I kind of think of this as a standard which originally started in Germany in the 1980s where we've got a very cold climate we've got maybe a grid system that could go down if you're in a climate it's 10 degrees outside and the power goes off if you have a traditional house that's leaky and not very well insulated how long is it gonna take to get uncomfortable and maybe even have some people not be able to be in their homes anymore what about pipes bursting all these things on the other hand if you build a super well insulated and super airtight house if the power went out and you were minus 10 out because your body's generating some heat you could probably live in a house if it was built well enough for several days without power and be ok now let's translate that now to America of passive house Institute you u.s. feeis we've kind of adopted our own standards here in America and we've said you know our climate isn't just Germany's climate right we've got Minnesota and Florida all in the same country Texas a very different climate zone than Germany a couple years ago they've kind of modified those standards a little bit and now we actually have a climate zone version of Passivhaus which means that I can build a slightly different house with slightly different standards in Texas than I am if I'm going to get a certified house in Boston or some other place now when we think about passive house we think very high levels of insulation very airtight in fact a bloater score that's crazy low we also have some components that are a part of that that need to be really good components and windows is a big part of that now when I started this project I wasn't thinking I was gonna be passive house in fact I expect all double-glazed you know windows and doors that would meet code but weren't crazy expensive nor were they crazy well insulated I'm working with children on this house and when I made some of the changes with kit from the remodel to a new build we upgraded some of the windows in the house not all of them to triple-glazed and I got at that point a passive Alice energy modeler involved who modeled the house and said actually if we have a mixture of double and triple glaze on the house and we switch out this front and back door to a more efficient unit than just a standard double glaze I think we're actually gonna make passive house standard this is the first kind of aha moment that I said gosh I should pursue that certification if if for no other reason that I want to teach people how to build really good houses and I want to encourage us as Americans us as Texans to build better and to build buildings that are gonna last like we have in other parts of the world I think we have had a tendency to build buildings that are related to the first cost and yet get torn down and aren't particularly efficient or comfortable or durable in the short lifespan that they have so this house is intended to be a little bit of a model for that I'll put a link to this in the description but they've changed with this climate specific Passivhaus institute us some of those standards so that for instance in climate zone 2 where we are here i need a mixture of windows double and triple glazed that are going to end up with an overall u factor of 0.18 now code in our air somewhere around 0.32 i believe for you factor so I can have some double glazed windows I'm also gonna need some triple glazed in some very efficient units and for solar heat gain coefficient as long as we're below point three we're gonna make their standards what else did I miss I think that's it on passive house for now there's so much more that could be said but the idea of passive house is super well insulated super airtight and then we're gonna bring fresh filtered air in on our terms and here in the South we're gonna use an ERV an energy recovery ventilator so that we can also exchange some that moisture we're gonna use a dehumidifier in this house I've been working with my friends at positive energy if you're here in Austin you know them great mechanical designers they've done a fantastic design for me I'm gonna be using all Mitsubishi equipment we've got very small equipment I don't have a lot of load on this house and then we're gonna use a Zender unit for fresh air so we've got just a little puffs of fresh air going into all my bedrooms and my main spaces all the time that's filtered air and it's balanced ventilation so when I bring air in I'm put I'm pushing air out at the same time I've got a daughter that has asthma and I really want to make sure that this is a very very clean air house I don't want any allergens in the air and I want to make sure this is very healthy air and then lastly I haven't quite worked out all the details yet but I'm interested in this house being a net zero or a net positive house and I think this is why I like passive house so much and why it's intrigued me so much is that if we build to this standard it's really not gonna take a lot of solar on the roof and I like solar because it's a it's a static system once you set it and forget it there's no moving parts there's no maintenance really there's nothing that needs to be done that if I put enough on I could be net positive I could actually back to Austin energy and get paid for more energy than I'm even using in the house I have a feeling we'll have some questions and comments in that and we're gonna get into more of this in the future but kid why don't we go upstairs we'll talk a little bit about the upstairs design and then maybe we could pop out onto this real flat roof right above oh so you talked about a few of the details outside it'll be good I will meet you upstairs kid I love the stairwell man I think this light in here once we do some wood walls in here it's really gonna bathe that downstairs in life that's such a such a feature on the house I live in a about a 2,100 square foot house now with four four kiddos and we just have one main living space there's no secondary space and as my kids are transitioning into the teen years we've got kids coming over we've got friends there's nowhere to go except for just all in one space so having this secondary room is gonna be incredible for us walk me through what's happening upstairs are actually yeah so this has become what's been dubbed now as the teen room says they're sequestered off they've got their own space you know where this all really happened was that's where the stair was originally and this whole floor plane was chopped up and then we've added about twelve feet really about it's about right here and then from over here this is all new floor we've extended over the existing roof yeah stair was over there so what that allowed us is to give you know big sister the big room we've got that you know rid of the stair yeah so my daughter's in this larger bedroom she has her own her own bathroom over here yep which is really nice own bathroom great natural light plenty of closet space but that getting rid of that stair helps so much to give us that and she's got her own world here away from the boys and so the boys she's 14 and then I've got three boys behind her that are all two years apart and they're all gonna be down here in their own bedroom and as we're going by this space - this is probably my wife's second favorite space in the house which is a linen closet which we don't have in our current spot so having a spot for linens amazing and then this room is my bunk room so basically I'm hoping that my boys will for many years until they're out of the house stay in the same bedroom I figure you're gonna have a roommate your whole life might as well not have your own bedroom as a kid right it's so cool they're all gonna be in here and they're their own little deal you can lock them off yeah they're completely at this side of the house yeah they almost have a little suite back here in some respects so we've got one one window for each one of their beds one big closet here and then there will be a sliding barn door here and then this room will end up being kind of a secondary bedroom living space maybe if they have friends over for the night this would be an easy spot to have a second bed and then we've got now closet two in closet three as well so each one of the boys will have their own kind of closet space I think there's going to be a terrific space yeah and then the other space would hump a ladder at the second but if we were to pop upstairs to the Attic man kid I love this attic space when we transitioned from thinking about remodel to building new one of the things I said to you was you know how could we get a little bit more attic and storage space in Texas we don't have basements like I did grown up in the Northeast all our mechanicals are in our attics but all of our junk all of our stuff is in our garages and with four kids and bikes I got no room for a car I barely have room for my tools and my equipment so having an attic space incredible we worked with the Smiths structural engineering and whit Smith you guys from Austin probably know those guys been around 30 years with dad started the company and whit's a second-generation engineer I worked with him to design an l VL truss system for this roof so that we would have this giant open space plenty of room I'll have one of my Mitsubishi zones upstairs to take care of this floor my Zender fresh air unit will be upstairs as well but other than that I've got great storage space up there in plenty of room for future editions of mechanicals or whatever else I might need I didn't mention this but my hot water system for the house is going to be heat pump water heater system I'm going to use an 80 gal heat-pump we're gonna put that in the garage space within the garage to kind of make that part of the condition envelope what else am I missing up here just the fact back upstairs the Attic when we added a window there and just the huge difficult simple idea and then and really I mean you know yeah and back to the framing I mean that's kind of old-school I mean what's taking a more modern approach to it but it's like some of the houses we grew up with simple you know we're we've almost taken for granted but you're doing you know pre-engineered trusses that's like we forget that we don't have to do exactly it's like so it makes a huge difference yeah and those are more certainly than than an engineered truss system but to gain that kind of space for storage and of course my envelope is at the roofline right so my air-conditioning envelope my air sealed envelope is all the way up to the peak of the roof so all that storage space up there is within my air-conditioned envelope will insulate inside in the rafter space with some traditional bats but because I've got that four inches of rooftop insulation that space is is really going to be temperate and very very much the same temperature as the rest of the house okay why don't we when we pop out this window onto this real flat roof over here yeah and talk about a couple details outside yep meet you out there all right guys we're on the pop-out this is the second-story roof our first story roof us should say over my master these are those windows are gonna feed that light down in here and now you can see a couple of these details which is kind of fun here's my wall insulation right here and then here's the two layers of rooftop insulation you can see because we haven't run this yet these are gonna end up being triple-glazed jeld-wen windows and we we left this top foam off for the head flashing and all the other waterproofing that's going on there but it's kind of fun that you can see all those details and then the roof got framed on top of that now we did a slightly different detail here with these lvls on the flat and this overhangs only 16 inches whereas the rest of the house is 24 but talk to me about the roof it will come on here eventually kit well so what we're talking about you know we got the super low pitch and then that was a huge concern of yours but we really wanted to have that just kind of eyebrow flat look when you were looking at it from the street yeah and so the solution was because it's a small roof area is really just we think we can get a large enough piece of sheet metal to where we just have a single break right there in the middle to make the ridge and that way we're not gonna have any penetrations there's certainly no vents or anything coming through here so you know I think that was the win-win we're still getting that really you know flat eyebrow thing that was the original concept with this with this pop-up so then we'll do a standing seam metal roof on the rest of the roof and again I'm standing on the second layer of zip system sheathing so that really this is just my watershed layer but the layer below this is my air sealing layer let's talk about this gable next I love this view because now you can see on this gable this is my second storey pop-up over here that insulation is continuous all the way up to the peak of my roof and and basically rolls right on to my roof insulation so my roof deck is right here my wall insulation comes up I've got my two layers of roof insulation here then we'll put our hardy soffit on here coming down and then we've started putting our battens on it's really important when you've got a cladding on the outside of the house that have an air gap behind that cladding we want that hardiplank in this case that goes up on a batten system I still have battens to come here to have an air gap behind it so that any water that gets past that we can just hit that ventilation area and drain right out and not have a problem we'll put a bug screen at the top and the bottom that also allows me to take advantage of the foil facing that you're seeing on the outside of this foam this foil facing is going to act as a radiant barrier so when the Sun hits that hearty and any of those radiant rays to get back there are gonna get rejected by this if this was bad but it uptight a radiant barrier would not work it means that air gap in front of it and then this is a great spot to see what else we've got going on here that wall insulation went on the roof framing went on on top of that and now you can see all of my overhangs are bolted on after the fact so these overhangs then get bolted on with a real long power lag from spax that gets basically like a lag screw all the way back into the framing and now my overhang all this detail of my clothes soffit will look like a normal house everyone in the neighborhood's house looks similar but they have traditional vented rooms that are very very inefficient and in my case I've got an air-conditioned attic all of my Christmas decorations are gonna live within the same a seed space as the rest of my house because I've got this solid blanket of insulation on the outside with perfect wall style I don't need to worry about much BTUs from the sun's heat getting through very little is gonna make it through and what little makes it through I've got a very small mechanical system to cool or to heat in the wintertime and then I've got that fresh air ventilation system that's balanced to bring in fresh air when I need it and I've got a separate ultra air dehumidifier that's dehumidifier in my house air so this house is really gonna sip energy it's not gonna use a whole lot and this roof right here happens to be facing south and west perfect spot for me to do a small solar array to power the house I'm still working on some of those calculations so I don't have all that yet but it's coming soon we've got a great pitch to ya 312 yeah 312 so easy yeah um kid I think that's about it anything else you can think up too to close this out I think we've covered oh yeah we cover a lot yeah we did guys thanks for joining me if you're watching this from the AI a crane committing kitten are gonna do a live Q&A afterwards if you're watching this on YouTube I really appreciate you guys joining me I'll put a link to kit so you'll know his website in the description big thanks to Steve basic who couldn't be here amazing job in the details so many people have helped me along the way on this been a super fun project if you're not already a subscriber hit that subscribe button below we've got new content every Tuesday and every Friday follow me on Twitter Instagram otherwise we'll see you next time on the build show [Music]

Channel: Matt Risinger

Views: 260,582

Rating: 4.9052696 out of 5

Keywords: perfect wal, perfect wall, best wall construction, joe lstiburek, kit johnson architect, matt risinger, build show, matt's house, foam exterior insulation, atlas polyiso

Id: jjHOqbJ9ZeQ

Length: 42min 55sec (2575 seconds)

Published: Tue May 12 2020