Efficient home designs & insulation question

[Etxnoodler]

I'm still not really sold that there won't be mold issues down the road with foam. I personally built mine in 88 with 6" exterior walls and 2 layers of 6" batts ( yes 1 faced and 1 unfaced) in the attic. We keep the house at 70 and the heater has run for 51 total minutes since last night till now. Currently 31* outside. No fireplace burning.

This is kind of how I was thinking about going. For the same reasons.
Many of these comments seem to validate my concern about the foam. With unstable energy stuff that seems to be happening I would like to be able to open windows if we don’t have power for weeks on end for whatever reason, and not have mold problems.

[Etxnoodler]

Ttt

[tps7742]

This is kind of how I was thinking about going. For the same reasons.
Many of these comments seem to validate my concern about the foam. With unstable energy stuff that seems to be happening I would like to be able to open windows if we don’t have power for weeks on end for whatever reason, and not have mold problems.

Sounds like you answered your own question on the type of insulation you want.

[Mike D]

This is kind of how I was thinking about going. For the same reasons.
Many of these comments seem to validate my concern about the foam. With unstable energy stuff that seems to be happening I would like to be able to open windows if we don’t have power for weeks on end for whatever reason, and not have mold problems.

IMO you are worry about nothing to very low probability of happening.

If this was an issue of any consequence, you would hear actual cases of it, not “I think” and I heard from my cousin’s, brother’s, wife’s boyfriend said….


Sent from my iPad using Tapatalk Pro

[Biggs]

Fully encapsulated space with spray foam is the way to go.
If you’re really concerned about efficiency, keep the ceiling height standard.


Sent from my iPhone using Tapatalk

[rferg84]

Fully encapsulated space with spray foam is the way to go.
If you’re really concerned about efficiency, keep the ceiling height standard.


Sent from my iPhone using Tapatalk

Yep.

Spray foam is a game changer.

We have a total electric house, built last year, close to 4k sq ft with 3 units, 13' ceilings in the living kitchen and dining rooms and I haven't had an electric bill over $225. We aren't frugal about keeping it hot or cold.

Similar house we sold but 30 years old, same setup, no foam, would have cost us $4-600/month.

[Mike D]

Yep.

Spray foam is a game changer.

We have a total electric house, built last year, close to 4k sq ft with 3 units, 13' ceilings in the living kitchen and dining rooms and I haven't had an electric bill over $225. We aren't frugal about keeping it hot or cold.

Similar house we sold but 30 years old, same setup, no foam, would have cost us $4-600/month.

Very similar to our, at least until electricity rates shot up 60%.

I’m sure glad we have the foam insulation or it would be really bad.


Sent from my iPad using Tapatalk Pro

[txlawdog]

Before you decide on foam, listen to Tom Tynan on Homeshow radio (610 AM Houston) and call him and ask about the foams. People are sealing up their houses too tight. You have to have some circulation, like bringing in outside air to your unit. I can't explain it like he can. https://homeshowradio.com/

[Monark]

Before you decide on foam, listen to Tom Tynan on Homeshow radio (610 AM Houston) and call him and ask about the foams. People are sealing up their houses too tight. You have to have some circulation, like bringing in outside air to your unit. I can't explain it like he can. https://homeshowradio.com/

Before you listen to Tom Tynan, be advised he & others like him only endorse products & companies that pay for advertisements. I bet if some foam insulation company paid for a spot, Tom Tynan would just love foam insulation all of a sudden.

[Etxnoodler]

IMO you are worry about nothing to very low probability of happening.

If this was an issue of any consequence, you would hear actual cases of it, not “I think” and I heard from my cousin’s, brother’s, wife’s boyfriend said….


Sent from my iPad using Tapatalk Pro

The only person i know with foam that actually opens their windows had a mold problem. That’s when I started second guessing it.

Thread isn’t just about foam vs bat. Though
What about 2x6 exterior walls?
My south wall will be covered by a porch but since my west wall will catch full sun I was thinking about 2x6 framing for more insulation and only one small window on that side.
More windows on north and south side to increase air flow with windows.
Thoughts ?

[Txhunter3000]

Makes really good sense to me.

[Box-R]

There is always 'underground' for energy efficiency/insulation.

[Txhunter3000]

I've asked this in every foam thread to date and have never had an answer, so here goes. If you have rotted plywood under asphalt shingles or damaged barndominion metal roofing with foam attached to it, how will you replace it? Insurance is not an answer. I'm not saying it's due to mold, instead leakage or act of God.

Foam is also combustible, fiberglass isn't.

[Mike D]

I've asked this in every foam thread to date and have never had an answer, so here goes. If you have rotted plywood under asphalt shingles or damaged barndominion metal roofing with foam attached to it, how will you replace it? Insurance is not an answer. I'm not saying it's due to mold, instead leakage or act of God.

Foam is also combustible, fiberglass isn't.

The same way you would t
Replace any water damaged wood. Rip is out and replace it. Respect the foam. Batt insulation would be ruined as well so that’s no disadvantage. Also batt insulation holds water when wet so it can damage as bad or worse.

The spray foam has a flame retardant mixed in with it.


Sent from my iPhone using Tapatalk Pro

[bowhntrmatt]

The only person i know with foam that actually opens their windows had a mold problem. That’s when I started second guessing it.

Thread isn’t just about foam vs bat. Though
What about 2x6 exterior walls?
My south wall will be covered by a porch but since my west wall will catch full sun I was thinking about 2x6 framing for more insulation and only one small window on that side.
More windows on north and south side to increase air flow with windows.
Thoughts ?

I’ve done hundreds of load calculations as an HVAC pro. I’ll tell you that walls are pretty far down the list of heat gain sources in most homes. I personally would waste the money on a 2x6 exterior wall. You are on the right track, though. The main thing is to minimize glass facing S, SW, or W.

I’m personally a fan of spray foam, but have also seen plenty of terrible situations when homes are done wrong. Never have I heard of someone having mold issues because they left windows open…it’s usually houses that are too tight without enough make-up air that see issues like that.