Not shure about these double wall systems. Seems like more wood, more cost. Dence pack cellious on the exterior.hmmm, gonna have to think about that 1. I wish you would give more information about the exterior foam. (Type of foam,, density, open / closed cell, current cost.)
Nothing mysterious about double stud walls. We have a home, small shop, pump house and chicken house all built this way. Our heating bills are very small, a fraction of our neighbours' bills. Oh, we used blown-in cellulose on the larger buildings and two layers of Rockwool on the smaller ones. Both do a great job.
Great video but....... You talk about frost by the OSB behind the fiberglass insulation. You also talk about how the home looses moisture through your walls. You then show a product of foam on the outside that is not permeable, which causes an even more of a problem. MOLD, ROT, MILDEW on the exterior OSB. You MUST use a foam that breathes!!!! Not Dow or the product you show on the video. It must be an EPS product not an XPS that does NOT breathe.
Mildew seems like it would be a huge problem. I'm starting to think that the only mildew-proof option is full cavity spray foam with Zip-R sheathing, SIPS, or ICF. WIthout one of those, it seems like you're just begging for mildew.
What OSB? Frost was on PLYWOOD behind the fiberglass @ 7:20 . But non-permeable doesn't make good sense in certain builds and/or renovations; and therefore using a foam that "breaths" is NOT always a "MUST" as you dictated 2 years ago. Only in certain scenarios a breathing wall system is necessary. It's a tough go though; and it seems even the so-called experts can't get it right. It's basically all a shit show imo.
Good thing I found your website. I am a DTU student and we are doing a group project about exterior walls in the arctic and your website was like finding a gold mine for me.
Thank you!! Very informative. We are building our final home before retirement, and want to stay in this home as long as possible . If we can cut down on utilities, I look at this as an investment. Great job.
Excellent video explaining important issues, and applications, construction methods, regarding proper modern exterior insulation wall systems....Great job!
I put 1/2” o c pink foam on my inside walls under the s r 20 years ago. The insulation holds heat in but doesn’t keep the cold out. Only regret is more foam as the concept works. Sometimes I have to open a door before I go to bed to cool down some. Central Minnesota climate
If I lived in Alaska, I'd build a giant greenhouse around my house & yard warmed by the sun. If some arctic air blows in, my house would still be surrounded by 10ºF air instead of -30ºF air! Plus I wouldn't have to worry about forgetting my dogs outside or something.
After retro fit a.c. in my attic with 2nd floor return I've been noticing nail pops all over my home. And see old sheetrock seams (non cracking) but noticable. Any thoughts of what is going on? I also suspect stack effect because my wood stove stinks
Would it do any good to air/vapor barrier both interior and exterior of outside walls (after insulating outside and inside with that ridge foam insulation) Would it have any benefits to having it foil both on outside and inside foam board insulation also?
This would cause significant problems. You don't want to create a situation where moisture can get trapped between two vapor barriers, because you'll never get rid of it. Moisture will find it's way in, no matter what you do. Think rot, mold, etc. It's not good. People have tried this and learned the hard way!
Install an HRV or ERV...heat exchangers. This approach will pre-heat the fresh air coming into the house. A 100% efficient HRV will still mean losing 50% of the heat in the exhausted air...If outside is zero, and inside is 70F, the fresh air will be heated to 35F as it passes through the HRV. Or in a moderately tight house, you can have a continuous exhaust fan that creates a very small negative pressure in the house, so a little cold air leaks in, which is better than warm, moist air leaking out and condensing inside the walls.
When we finally get to build I want to add a ground-air-heat transfer (GAHT) system to the intake side of the ERV. This would decrease the delta between the inside and outside air. The trick is to get below the frost line. Here in Upper Michigan I have to go down 10-12’ to get 55 degrees. Alaska would be even deeper, and then there’s permafrost.
What is the opinion of rock wool insulation versus fiberglass insulation (the pink stuff)? I am told the rock wool is denser and holds its shape that lends itself to being installed more correctly even if installers are going fast. Does one product (of equal thickness) have more R value than the other?
I think they're both about the same in r value. Rockwool is more expensive, but does better with itchiness and water & fire issues. But it needs a vapor barrier on BOTH sides! Fiberglass traps pockets of air, Rockwool does not. Rockwool might be slightly better for sound quality, but not enough for any human to notice. Basically, I went with fiberglass because the Rockwool would have been 3" thick and my walls (and the fiberglass) were 3.5" thick. So I got better insulation using the space I had for less money. I have no idea why they make Rockwool in 3" batts.
Rockwool is slightly better than fibreglass. But just slightly. It's a pleasure to work with because it isn't as itchy. Yes, it is a bit more expensive but the extra cost is worth it. Rockwool does NOT require a vapour barrier on both sides! Where did you ever get an idea like that? ALL spun insulation, mineral or glass, traps air amongst the fibers. Don't believe me on these two points? Email the Green Building Advisor (a part of Fine Homebuilding Mag.) @@Hypercube9
@@paulmaxwell8851 Paul, you must be working with some VERY old houses then if you aren't using a vapor barrier on both sides! Newer houses require a smart membrane on the outside that will allow a houses walls to dry out. And you need a vapor barrier on the inside to keep inside moisture from showers, etc. from condensing inside the cold walls during the winter. But I was specifically talking about northern climates where I'm at (Michigan). So maybe the rules are different in the humid south or wherever you're at? Anyway, all the Roxul I've ever seen has been unfaced, so you're basically adding another step to your installation and the main cost of installation is labor so you're paying more for the insulation and then paying more again for the install! Anyway, if you're having someone else install your insulation, then why would you care if it's itchy or if it's a pleasure to work with? And if you're doing it yourself to save money, then why not just buy the fiberglass stuff and take the time to install it correctly? It really doesn't take any actual skill! Plus, I've never had a problem with itchiness around fiberglass. Or split the difference and buy rockwool but install it yourself! Besides, if a "bad install" means that you have air gaps where insulation should be, then Roxul doesn't prevent a bad install, it GUARANTEES IT!! Because like I said, it comes in 3" batts and a 2x4 wall will have a 3.5" air gap! So you're left with a half inch of air space that could be better filled with some EPS foam board or something! Adding even more to the cost and time to install! Not to mention whatever insulation type you choose, you'll still have the thermal bridge provided by the 2x4 studs! Enjoy having an R4 over 25% of your external walls!
from everything i've seen/researched over the last few weeks, i'd say yes it would but, the wood itself is not a good insulator so the studs will be cold bridges, better to go smaller on the studs and put your insulation on the outside of the house instead of the inside.
To avoid thermal bridging, you should build your 2x6 wall using 2x4's that are staggered with foam to fill the rest of the gap. You want a thicker wall, but you don't need a stronger wall! So using 2x8's just gives you a longer thermal bridge, more strength than you need (and it costs you money). Alternately, you could turn your 2x4's sideways, so again you would still have all the support you need, but you would have a thermal break filled with insulation between the wood and either the interior or exterior of the wall.
US American walls are so weird. In Europe for 500 years houses were insulated as follows: wood frame filled with bricks or a straw-Clay mixture. The inside was covered with an air tight layer of more straw-clay mix on the inside. Now we live in modern Europe and still use stones, wood and clay, but also use wood fiber or hemp fiber for insulation. The massive advantage: moisture is no problem at all, even a pipe leak will just dry. The other advantage is how soundproof out walls are and how pleasant they reflect sound. So, what is important with additional insulation on the outside: the roof has to be extended to protect the walls, or they will receive too much rain.
The thing is that controlling moisture levels with MECHANICAL VENTILATION costs EXTRA MONEY and Energy! I don't buy it to the MODERN WALL implications that they are superior; because, I live in a 1974 fiberglass cavity & attic 2x4 framed upstairs (with that old fiberboard sheathing and fiberboard siding) and cinder block basement, it's pretty much always over 50% Humidity Outside (Usually 80%) and inside it maintains around 50% humidity by itself in the cold season with electric baseboard heaters (upstairs and downstairs)! The only improvements I've done is seal up electrical boxes and spray foamed cavities around windows. - 50% Humidity is pretty much ideal yes? I just want to lower my electric bill when it gets really below freezing. Am thinking about removing all fiberboard, adding 2" plain old EPS (Higher density maybe) and plastic siding with maybe the molded EPS as well; but I can't find much info that might support that it will work before doing all the work. I want the wall cavity to breath but not condense water vapor. - I was thinking of adding strapping outside and throwing on a foil reflector to keep the wall warmer and hopefully prevent frost creation in the main wall, but too many unknowns and too much shit going on to think it through.
nice job thx you
The REMOTE wall video series covers the exterior foam board in greater detail. Both videos are on this channel. Sorry, I can't post links here.
So with the new construction and the REMOTE wall system you still blow insulation into the inside of the wall?
Not shure about these double wall systems. Seems like more wood, more cost. Dence pack cellious on the exterior.hmmm, gonna have to think about that 1. I wish you would give more information about the exterior foam. (Type of foam,, density, open / closed cell, current cost.)
Nothing mysterious about double stud walls. We have a home, small shop, pump house and chicken house all built this way. Our heating bills are very small, a fraction of our neighbours' bills. Oh, we used blown-in cellulose on the larger buildings and two layers of Rockwool on the smaller ones. Both do a great job.
Great video but....... You talk about frost by the OSB behind the fiberglass insulation. You also talk about how the home looses moisture through your walls. You then show a product of foam on the outside that is not permeable, which causes an even more of a problem. MOLD, ROT, MILDEW on the exterior OSB. You MUST use a foam that breathes!!!! Not Dow or the product you show on the video. It must be an EPS product not an XPS that does NOT breathe.
Mildew seems like it would be a huge problem. I'm starting to think that the only mildew-proof option is full cavity spray foam with Zip-R sheathing, SIPS, or ICF. WIthout one of those, it seems like you're just begging for mildew.
What OSB? Frost was on PLYWOOD behind the fiberglass @ 7:20 . But non-permeable doesn't make good sense in certain builds and/or renovations; and therefore using a foam that "breaths" is NOT always a "MUST" as you dictated 2 years ago. Only in certain scenarios a breathing wall system is necessary. It's a tough go though; and it seems even the so-called experts can't get it right. It's basically all a shit show imo.
Good thing I found your website.
I am a DTU student and we are doing a group project about exterior walls in the arctic and your website was like finding a gold mine for me.
Thank you!! Very informative. We are building our final home before retirement, and want to stay in this home as long as possible . If we can cut down on utilities, I look at this as an investment. Great job.
Excellent video explaining important issues, and applications, construction methods, regarding proper modern exterior insulation wall systems....Great job!
I put 1/2” o c pink foam on my inside walls under the s r 20 years ago. The insulation holds heat in but doesn’t keep the cold out. Only regret is more foam as the concept works. Sometimes I have to open a door before I go to bed to cool down some. Central Minnesota climate
If I lived in Alaska, I'd build a giant greenhouse around my house & yard warmed by the sun. If some arctic air blows in, my house would still be surrounded by 10ºF air instead of -30ºF air! Plus I wouldn't have to worry about forgetting my dogs outside or something.
What if you have an 1950s log house and you cannot add insulation on the outside?
After retro fit a.c. in my attic with 2nd floor return I've been noticing nail pops all over my home. And see old sheetrock seams (non cracking) but noticable. Any thoughts of what is going on? I also suspect stack effect because my wood stove stinks
Drying sheetrock and shrinking?
Really well explained . . . great job . Thank you
Would it do any good to air/vapor barrier both interior and exterior of outside walls (after insulating outside and inside with that ridge foam insulation) Would it have any benefits to having it foil both on outside and inside foam board insulation also?
This would cause significant problems. You don't want to create a situation where moisture can get trapped between two vapor barriers, because you'll never get rid of it. Moisture will find it's way in, no matter what you do. Think rot, mold, etc. It's not good. People have tried this and learned the hard way!
Awesome video. Very informative.
After you seal the house up basically air tight, the how do you mechanically ventilate? Going to have to crack a window and let in some fresh air?
Install an HRV or ERV...heat exchangers. This approach will pre-heat the fresh air coming into the house. A 100% efficient HRV will still mean losing 50% of the heat in the exhausted air...If outside is zero, and inside is 70F, the fresh air will be heated to 35F as it passes through the HRV. Or in a moderately tight house, you can have a continuous exhaust fan that creates a very small negative pressure in the house, so a little cold air leaks in, which is better than warm, moist air leaking out and condensing inside the walls.
if u install continuous exhust fan warm air is still gunna leak out it... @@fredygump5578
When we finally get to build I want to add a ground-air-heat transfer (GAHT) system to the intake side of the ERV. This would decrease the delta between the inside and outside air. The trick is to get below the frost line. Here in Upper Michigan I have to go down 10-12’ to get 55 degrees. Alaska would be even deeper, and then there’s permafrost.
What is the opinion of rock wool insulation versus fiberglass insulation (the pink stuff)? I am told the rock wool is denser and holds its shape that lends itself to being installed more correctly even if installers are going fast. Does one product (of equal thickness) have more R value than the other?
I think they're both about the same in r value. Rockwool is more expensive, but does better with itchiness and water & fire issues. But it needs a vapor barrier on BOTH sides! Fiberglass traps pockets of air, Rockwool does not. Rockwool might be slightly better for sound quality, but not enough for any human to notice.
Basically, I went with fiberglass because the Rockwool would have been 3" thick and my walls (and the fiberglass) were 3.5" thick. So I got better insulation using the space I had for less money. I have no idea why they make Rockwool in 3" batts.
Rockwool is slightly better than fibreglass. But just slightly. It's a pleasure to work with because it isn't as itchy. Yes, it is a bit more expensive but the extra cost is worth it.
Rockwool does NOT require a vapour barrier on both sides! Where did you ever get an idea like that? ALL spun insulation, mineral or glass, traps air amongst the fibers. Don't believe me on these two points? Email the Green Building Advisor (a part of Fine Homebuilding Mag.) @@Hypercube9
@@paulmaxwell8851 Paul, you must be working with some VERY old houses then if you aren't using a vapor barrier on both sides! Newer houses require a smart membrane on the outside that will allow a houses walls to dry out. And you need a vapor barrier on the inside to keep inside moisture from showers, etc. from condensing inside the cold walls during the winter. But I was specifically talking about northern climates where I'm at (Michigan). So maybe the rules are different in the humid south or wherever you're at? Anyway, all the Roxul I've ever seen has been unfaced, so you're basically adding another step to your installation and the main cost of installation is labor so you're paying more for the insulation and then paying more again for the install!
Anyway, if you're having someone else install your insulation, then why would you care if it's itchy or if it's a pleasure to work with? And if you're doing it yourself to save money, then why not just buy the fiberglass stuff and take the time to install it correctly? It really doesn't take any actual skill! Plus, I've never had a problem with itchiness around fiberglass. Or split the difference and buy rockwool but install it yourself!
Besides, if a "bad install" means that you have air gaps where insulation should be, then Roxul doesn't prevent a bad install, it GUARANTEES IT!! Because like I said, it comes in 3" batts and a 2x4 wall will have a 3.5" air gap! So you're left with a half inch of air space that could be better filled with some EPS foam board or something! Adding even more to the cost and time to install! Not to mention whatever insulation type you choose, you'll still have the thermal bridge provided by the 2x4 studs! Enjoy having an R4 over 25% of your external walls!
Rock wool would make home more fire resistant and quieter.
Would building with 2 x 8 afford the opportunity to use more insulation?
from everything i've seen/researched over the last few weeks, i'd say yes it would but, the wood itself is not a good insulator so the studs will be cold bridges, better to go smaller on the studs and put your insulation on the outside of the house instead of the inside.
To avoid thermal bridging, you should build your 2x6 wall using 2x4's that are staggered with foam to fill the rest of the gap. You want a thicker wall, but you don't need a stronger wall! So using 2x8's just gives you a longer thermal bridge, more strength than you need (and it costs you money). Alternately, you could turn your 2x4's sideways, so again you would still have all the support you need, but you would have a thermal break filled with insulation between the wood and either the interior or exterior of the wall.
@@quantaca5773why not inside
US American walls are so weird. In Europe for 500 years houses were insulated as follows: wood frame filled with bricks or a straw-Clay mixture. The inside was covered with an air tight layer of more straw-clay mix on the inside.
Now we live in modern Europe and still use stones, wood and clay, but also use wood fiber or hemp fiber for insulation. The massive advantage: moisture is no problem at all, even a pipe leak will just dry.
The other advantage is how soundproof out walls are and how pleasant they reflect sound.
So, what is important with additional insulation on the outside: the roof has to be extended to protect the walls, or they will receive too much rain.
The thing is that controlling moisture levels with MECHANICAL VENTILATION costs EXTRA MONEY and Energy! I don't buy it to the MODERN WALL implications that they are superior; because, I live in a 1974 fiberglass cavity & attic 2x4 framed upstairs (with that old fiberboard sheathing and fiberboard siding) and cinder block basement, it's pretty much always over 50% Humidity Outside (Usually 80%) and inside it maintains around 50% humidity by itself in the cold season with electric baseboard heaters (upstairs and downstairs)! The only improvements I've done is seal up electrical boxes and spray foamed cavities around windows. - 50% Humidity is pretty much ideal yes? I just want to lower my electric bill when it gets really below freezing. Am thinking about removing all fiberboard, adding 2" plain old EPS (Higher density maybe) and plastic siding with maybe the molded EPS as well; but I can't find much info that might support that it will work before doing all the work. I want the wall cavity to breath but not condense water vapor. - I was thinking of adding strapping outside and throwing on a foil reflector to keep the wall warmer and hopefully prevent frost creation in the main wall, but too many unknowns and too much shit going on to think it through.