I think it's great. I studied the diagrams. Prevent dew point from being on surface of sheathing. Cover house in a blanket. The main issue is the cost. I wish it were affordable.
haha sorta. the outer layer isn't structural, it's just the blanket. the inner wall is structure only, not insulating. Meanwhile my 100 year old house has no insulation ☹
You can do it cheap or do it right, which isn't much more costly if you choose your materials wisely. I'll never understand people who expect to get a high quality, durable, comfortable, efficient building without following the basic principals of building science.
I’ve been improving my grandfathers cabin that I’ve owned for 10 years. The exterior is vertical log and they are soft at the lower end that were exposed to deep snow over the years. The studs are impeccable do to the 60 lb felt that was used between the exterior and framing. I’m a true believer in 60lb tar paper.
I thought Zip Systems’ outer green membrane is 13 perms, whereas the OSB underneath is 1-3 perms. Doesn’t that make your OSB your vapor control layer? It’s okay in winter, when the OSB is hot, and the hot humid air leaks out into the rock wool, because rock wool doesn’t mind being wet/humid. But in summer, the Zip OSB will be as cold as the interior air conditioning, and Zip System will allow humid outside air to contact the cold OSB. Is 13 perms enough to prevent the OSB from getting too moisture saturated? Are you expecting drying to the interior through the OSB to keep it dry in summer?
I have read many articles by Prof. Lstiburek. As he says wood burns and rots. I am an architect i Europe and in practice we do Perfect Wall without using wood. The main wall is brick. And the cladding is attached to aluminum studs. The insulation is always mineralwool. As a finish we use Knauf Aqua white cementous Panel.
I'm designing a house in australia and we have very different climate criteria but I'm also looking at a masonry structure with cementitious exterior cladding. Essentially it sounds like you are talking about what we would call "reverse brick veneer" but was surprised by your "aluminum studs". Do you just mean metal studs that hold the insulation layer? I imagine that would be worse for thermal bridging...
Hybrid designs are becoming more popular using a combination of materials and purposeful layers. Efforts are made to prevent thermal bridging across structural supports, all while not sacrificing living space.
Polyiso is my preferred method to care for the continuous insulation control as it has the highest R-Value per inch. This way you don’t have to to try to find 13 inch screws. We can meet that same R-value with 4 inches of one polyiso board.
We try to keep moisture going outward in our timber frames. People don't understand how much moisture builds in a house. Block walls we core with vermiculite, mineral wool batts and board, low perm air barrier, air gap, and masonry veneer. Wall ties for masonry veneer hold the mineral wool.
Interesting that you can run the Rockwool and furring right down to grade with no drip edge, nothing. Definitely not code in the majority of the country.
Wow. Awesome. What fastener manufacturer are those 12" Galvy screws? Also, Is there a chart somewhere that says the minimum of exterior rockwool to use based on location?
nope, the comfortboard is pretty dense and there are different ratings for it. where he talked about comfortboard 80, he quickly mentioned comfortboard 110 under the slab. when weight is distributed evenly you can load quite a bit on top of that rockwool
definatley rigid on the bottom foot or 2 feet instead of that, you can see the water being absorbed from the ground. Or vapour barrier rapped around the front of it when drainage to the back.
How are you ensuring the furring strips are evenly fastened? (i.e. a flat surface across the entire wall assembly for the cladding and not compressing the mineral wool potentially reducing it's effective r-value?)
I dont understand. Build a cinder block wall seal the outside and build a 2nd cinder bolck two ft from the first and fill with dry sand. Low tech, all materials are available in bulk and great thermal properties. What am i missing?
Interesting idea but if you fill the cavity make sure no rain or moisture gets in there, also check the r-value of two ft of sand plus cinder block; Probably ok but not great. Lastly, better use some next level wall ties to stop the wall from bursting apart!
I'd just use Zip-R12 and skip all the freakin labor intensive detail of mineral wool and furring strips with window buck extensions etc. The more wall insulation you add after R-30 (Zip R-12 plus closed cell between 2x4 studs) the more you have diminishing returns of cost to build/energy consumption. With this method, your wall thickness will be the same as if using 2x6 studs and windows will fit without custom extensions. You can build something like R-50 walls and triple pane windows but you'll never see a positive energy return compared to the cost of this build method unless you live above the arctic circle. Design your house with large roof overhangs and you eliminate a great deal of water intrusion problem areas, especially around windows. You also reduce thermal gain with less direct sunlight coming through glass. Eliminate roof valleys and you'll have less chance of water damage. You can spend as much as you like with complicated mineral wool over regular sheathing (OSB or plywood) but you won't get it back when you sell. The dream of spending the rest of your days in your home applies to very few. I think it's foolish to overbuild to this extent. The high R-values literally go out the window with new home owners wanting many large window panes, which are around R-3 or spend a lot more to get R-5+ triple pane glass. Investing is a super duper insulated home is not an investment.
It is difficult to put together a wall assembly without at least minimally conductive elements penetrating through the insulation. Not crazy about some of the elements in their wall assembly but the principal of building the envelope outside of the structure is spot on. Not only does it keep the structural elements at a relatively consistent temperature and humidity, it is far easier to execute a good quality envelope building layers from inside to out, entirely from the exterior.
@@bopodoq3069 I agree that the method is far superior to 2x4 or 2x6 construction with void insulation. The video is called the perfect wall...which this is not.
How would you improve it? I'm planning to use 2x ledger boards attached to the sheathing to eliminate any continuous thermal bridging, and as a bonus it will provide a much larger target for the screws used to attach the furring strips. I'll just add another 1-1.5" of insulation to compensate.
I think that much Rockwool is overkill. Just look at the sample they set on fire with a device inside the rockwool built house (19:20). Its not a 6 to 12 inch thick wall, and probably only 1.5 to 2 inch thick. So having this in mind the heat wont penetrate through the 1.5 to 2 inch and keeps the humidity on the outside if that is a concern and then space between the sheathing and rockwool should be in balance (not fluctuating in temp).
The figures don't lie. The more insulation, the less watts of energy needed to heat or cool the house. Properly built Passive is way more energy efficient and therefore far cheaper in the long run.
work with nature not against it . stick framing inevitably requires one to control a weakness in design . american stick framing was /is all about saving cost . there is no aspect of longevity built into the system , only price first everything else second . it's appears to be an American as the price above all else i see in everything we purchase , from houses to cars to gas to food etc etc. The current attempts to increase energy efficiency involves additional lumber but in the same configuration that creates so many problems . for a relative small increase in wood , one could use mass timber in the form of manufactured kiln dried logs or CLT panels for the exterior walls . the mass aspect of thick timber acts as a heat storage medium and controls humid changes due to its hygroscopic effect . installing wood fiber insulation panels on the OUTSIDE of the walls eliminates thermal bridging as the mass timber is all the same density. on top of the exterior insulation ,furring strips are attached vertically to accept a siding of choice . the space between the strips acts as an air vent to wick moisture away . the vents are open at the top and bottom with insect and rodent screen installed . the extra cost of the timber is offset by decreased labor .the exterior walls when precut can be assembled in only a few days . the roof structure can be quickly assembled to close the structure in . also there is a saving in no additional work is required on the inside walls and the exterior siding protects the insulation and the mass timber from the elements .
Skip ALL this and go with ICF. Alot quicker to install the same or more insulation value overall and it doubles as an air barrier. Couple with an ERV and foamed roof and you control the air ten times better. Good friend has 4500 sqft house and his entire utility bill (gas, elec, and water) in the middle of the Oklahoma summer was less than 200.
Stick framed walls have to be the most unnecessarily complicated, weak, and expensive way to build a house. Instead of wasting time in outdated technology originally developed to build cheap homes after WWII, how about further developing and building ICF, ICCF, insulated CMU, 3D printed homes?
Wood framing is still sustainable and captures carbon, unlike concrete products which have a huge environmental impact. Wood framing also allows for greater customization. And if you're familiar with it then it's not complicated.
Municipal building inspections and approvals do not know what to do with an ICF house, and won't approve building permits, making the standard stick framing an attractive option to builders that want to make money. Sad = true.
desings like this are becoming a lot popular over time, i hope to see more of these
Wow!
I think I will just wear an extra shirt.
I think it's great. I studied the diagrams. Prevent dew point from being on surface of sheathing. Cover house in a blanket.
The main issue is the cost. I wish it were affordable.
The same amount of insulation on the outside as in the inside just far easier on the outside less cutting no wires etc.
Got it. Frame up two houses, one inside the other.
haha sorta. the outer layer isn't structural, it's just the blanket. the inner wall is structure only, not insulating.
Meanwhile my 100 year old house has no insulation ☹
Cool...next do the affordable wall. 😂
You can do it cheap or do it right, which isn't much more costly if you choose your materials wisely. I'll never understand people who expect to get a high quality, durable, comfortable, efficient building without following the basic principals of building science.
I’ve been improving my grandfathers cabin that I’ve owned for 10 years. The exterior is vertical log and they are soft at the lower end that were exposed to deep snow over the years. The studs are impeccable do to the 60 lb felt that was used between the exterior and framing. I’m a true believer in 60lb tar paper.
Can you explain what the other control layers below grade are going to be for the stucco? You completely skipped what that is.
I thought Zip Systems’ outer green membrane is 13 perms, whereas the OSB underneath is 1-3 perms. Doesn’t that make your OSB your vapor control layer? It’s okay in winter, when the OSB is hot, and the hot humid air leaks out into the rock wool, because rock wool doesn’t mind being wet/humid. But in summer, the Zip OSB will be as cold as the interior air conditioning, and Zip System will allow humid outside air to contact the cold OSB. Is 13 perms enough to prevent the OSB from getting too moisture saturated? Are you expecting drying to the interior through the OSB to keep it dry in summer?
I have read many articles by Prof. Lstiburek. As he says wood burns and rots.
I am an architect i Europe and in practice we do Perfect Wall without using wood. The main wall is brick. And the cladding is attached to aluminum studs. The insulation is always mineralwool. As a finish we use Knauf Aqua white cementous Panel.
I'm designing a house in australia and we have very different climate criteria but I'm also looking at a masonry structure with cementitious exterior cladding. Essentially it sounds like you are talking about what we would call "reverse brick veneer" but was surprised by your "aluminum studs". Do you just mean metal studs that hold the insulation layer? I imagine that would be worse for thermal bridging...
Solid masonry walls aren’t possible in a lot of US- earthquakes or even shifting soils. Need more flexibility in structure.
Hybrid designs are becoming more popular using a combination of materials and purposeful layers. Efforts are made to prevent thermal bridging across structural supports, all while not sacrificing living space.
Polyiso is my preferred method to care for the continuous insulation control as it has the highest R-Value per inch. This way you don’t have to to try to find 13 inch screws. We can meet that same R-value with 4 inches of one polyiso board.
We try to keep moisture going outward in our timber frames. People don't understand how much moisture builds in a house. Block walls we core with vermiculite, mineral wool batts and board, low perm air barrier, air gap, and masonry veneer. Wall ties for masonry veneer hold the mineral wool.
Best walls in my opinion are ICF walls. Followed by a normal wall with closed cell spray foam and proper water barrier on the exterior.
Nice passive vent system for radon. Is there a low level air-in pipe, as I imagine it needs to pull from somewhere to work efficiently?
Interesting that you can run the Rockwool and furring right down to grade with no drip edge, nothing. Definitely not code in the majority of the country.
I thought the same.. super weird. Building 101 is get wicking materials off the floor
@@1stkeyhomebuyers Rockwool doesn't wick moisture
@@srchubz ...maybe... But have it sitting in it
Critters will still move in without a hardware cloth at the bottom
Wow. Awesome. What fastener manufacturer are those 12" Galvy screws? Also, Is there a chart somewhere that says the minimum of exterior rockwool to use based on location?
Home Depot sells for more than $1 each
Fantastic video.
Excellent content I can’t wait for better audio on future videos
what are the furring strips and rockwool resting on to prevent wicking and bug entrance?
I believe that rockwool acts as it’s own big screen. The fiber shreds any exoskeleton on bugs. Not sure on that so do your own due diligence
Why not just use SIPs???
Not sure if this is a dumb question but would the concrete slab crush the Rockwool insulation underneath and compromise its insulation rating?
nope, the comfortboard is pretty dense and there are different ratings for it. where he talked about comfortboard 80, he quickly mentioned comfortboard 110 under the slab. when weight is distributed evenly you can load quite a bit on top of that rockwool
@@janoserdelyi9879 Good to know, thanks!
definatley rigid on the bottom foot or 2 feet instead of that, you can see the water being absorbed from the ground. Or vapour barrier rapped around the front of it when drainage to the back.
Which brand or type of long screws did you use for the exterior wall and roof?
How can we apply these concepts in a renovation context? Is it possible to do this without redoing the frame itself?
How are you ensuring the furring strips are evenly fastened? (i.e. a flat surface across the entire wall assembly for the cladding and not compressing the mineral wool potentially reducing it's effective r-value?)
String lines
A 2 foot thick Cob wall sounds less expensive
I dont understand. Build a cinder block wall seal the outside and build a 2nd cinder bolck two ft from the first and fill with dry sand. Low tech, all materials are available in bulk and great thermal properties. What am i missing?
Interesting idea but if you fill the cavity make sure no rain or moisture gets in there, also check the r-value of two ft of sand plus cinder block; Probably ok but not great. Lastly, better use some next level wall ties to stop the wall from bursting apart!
I'd just use Zip-R12 and skip all the freakin labor intensive detail of mineral wool and furring strips with window buck extensions etc. The more wall insulation you add after R-30 (Zip R-12 plus closed cell between 2x4 studs) the more you have diminishing returns of cost to build/energy consumption. With this method, your wall thickness will be the same as if using 2x6 studs and windows will fit without custom extensions.
You can build something like R-50 walls and triple pane windows but you'll never see a positive energy return compared to the cost of this build method unless you live above the arctic circle.
Design your house with large roof overhangs and you eliminate a great deal of water intrusion problem areas, especially around windows. You also reduce thermal gain with less direct sunlight coming through glass. Eliminate roof valleys and you'll have less chance of water damage.
You can spend as much as you like with complicated mineral wool over regular sheathing (OSB or plywood) but you won't get it back when you sell. The dream of spending the rest of your days in your home applies to very few.
I think it's foolish to overbuild to this extent. The high R-values literally go out the window with new home owners wanting many large window panes, which are around R-3 or spend a lot more to get R-5+ triple pane glass. Investing is a super duper insulated home is not an investment.
Interesting points… especially with the windows and sky lights.
how expensive were those 12" screws? good grief
So thermal bridging and barrier pentation every time you install a 12" screw that is super conductive and a water channel. Awesome
It is difficult to put together a wall assembly without at least minimally conductive elements penetrating through the insulation. Not crazy about some of the elements in their wall assembly but the principal of building the envelope outside of the structure is spot on. Not only does it keep the structural elements at a relatively consistent temperature and humidity, it is far easier to execute a good quality envelope building layers from inside to out, entirely from the exterior.
@@bopodoq3069 I agree that the method is far superior to 2x4 or 2x6 construction with void insulation. The video is called the perfect wall...which this is not.
I my opinion the most perfect wall construction method currently is ICF. It’s still not perfect but it’s the best I have found so far.
What would you do differently?
How would you improve it?
I'm planning to use 2x ledger boards attached to the sheathing to eliminate any continuous thermal bridging, and as a bonus it will provide a much larger target for the screws used to attach the furring strips. I'll just add another 1-1.5" of insulation to compensate.
isn't it radon is radioactive? 🤔🤔🤔
rockwool doesn't burn but what about wood studs 😅.....
I think that much Rockwool is overkill. Just look at the sample they set on fire with a device inside the rockwool built house (19:20). Its not a 6 to 12 inch thick wall, and probably only 1.5 to 2 inch thick. So having this in mind the heat wont penetrate through the 1.5 to 2 inch and keeps the humidity on the outside if that is a concern and then space between the sheathing and rockwool should be in balance (not fluctuating in temp).
The figures don't lie. The more insulation, the less watts of energy needed to heat or cool the house. Properly built Passive is way more energy efficient and therefore far cheaper in the long run.
work with nature not against it . stick framing inevitably requires one to control a weakness in design . american stick framing was /is all about saving cost . there is no aspect of longevity built into the system , only price first everything else second . it's appears to be an American as the price above all else i see in everything we purchase , from houses to cars to gas to food etc etc.
The current attempts to increase energy efficiency involves additional lumber but in the same configuration that creates so many problems .
for a relative small increase in wood , one could use mass timber in the form of manufactured kiln dried logs or CLT panels for the exterior walls . the mass aspect of thick timber acts as a heat storage medium and controls humid changes due to its hygroscopic effect . installing wood fiber insulation panels on the OUTSIDE of the walls eliminates thermal bridging as the mass timber is all the same density. on top of the exterior insulation ,furring strips are attached vertically to accept a siding of choice . the space between the strips acts as an air vent to wick moisture away . the vents are open at the top and bottom with insect and rodent screen installed . the extra cost of the timber is offset by decreased labor .the exterior walls when precut can be assembled in only a few days . the roof structure can be quickly assembled to close the structure in . also there is a saving in no additional work is required on the inside walls and the exterior siding protects the insulation and the mass timber from the elements .
10 years from now, this will all be different. Also, wouldn't the homeowner have gotten off cheaper by insulating with bales of dollar bills?
I do not believe this system would work in a high wind application where we deal with140 and 150mph wind.
The voce made a false statement that wall system is good for cold climate, for Texas and Florida you have to put vapor barrier on outside
Skip ALL this and go with ICF. Alot quicker to install the same or more insulation value overall and it doubles as an air barrier. Couple with an ERV and foamed roof and you control the air ten times better. Good friend has 4500 sqft house and his entire utility bill (gas, elec, and water) in the middle of the Oklahoma summer was less than 200.
No way to make a perfect wall if you are using Zip as water control
promo sm
Stick framed walls have to be the most unnecessarily complicated, weak, and expensive way to build a house. Instead of wasting time in outdated technology originally developed to build cheap homes after WWII, how about further developing and building ICF, ICCF, insulated CMU, 3D printed homes?
Wood framing is still sustainable and captures carbon, unlike concrete products which have a huge environmental impact. Wood framing also allows for greater customization. And if you're familiar with it then it's not complicated.
Municipal building inspections and approvals do not know what to do with an ICF house, and won't approve building permits, making the standard stick framing an attractive option to builders that want to make money. Sad = true.
Agreed, ICF systems are superior on many levels.
"This promotion is brought to you by, the national ICF dealers and installers association...."
ICF is expensive as hell
main building material wood have worst material build wall. not perfect newer can do. need use hollow block and lot more insulation.
The perfect wall isn't made with wood
It can be built with a variety of materials, including wood.