Building a House with Wood

[Harvey]

I don't know if that's the right thread title. Knowing me I will change it 2 or 3 times.

Please note, that anyone who suggests changes to my stamped plans will be banned for one year.

The building code has raised the bar.

Walls have to be 2x6" now, I really like that. I didn't even know it was code, until I asked if we could build it that way.

I have a question about insulation.

Seems like foam for the ceiling/roof and regular insulation for the walls is a good compromise to me: efficiency, breathability, vocs and cost.

Obviously you want a carefully laid layer of tyvek or something to seal it.

But it seems the best performing walls have some kind of BREAK to disrupt the thermal bridge* created by the studs. *(Any solid connection between the inside and outside wall.)

It's not hard to imagine ways to do it. But it seems hard to come up with a good inexpensive ways to break that thermal bridge.

Ideas?

 

[Sbob]

I don't know if that's the right thread title. Knowing me I will change it 2 or 3 times.

Please note, that anyone who suggests changes to my stamped plans will be banned for one year.



Walls have to be 2x6" now, I really like that. I didn't even know it was code, until I asked if we could build it that way.

I have a question about insulation.

Seems like foam for the ceiling/roof and regular insulation for the walls is a good compromise to me: efficiency, breathability, vocs and cost.

Obviously you want a carefully laid layer of tyvek or something to seal it.

But it seems the best performing walls have some kind of BREAK to disrupt the thermal bridge* created by the studs. *(Any solid connection between the inside and outside wall.)

It's not hard to imagine ways to do it. But it seems hard to come up with a good inexpensive ways to break that thermal bridge.

Ideas?

It’s been 20 years since I built my last house, but using foam over the exterior sheathing is a good way to create a thermal break . Any insulation upgrade will pay dividends going forward as energy expense is only going to increase. I understand now there is some vinyl siding that is insulated
I actually built a house with 2x10 walls. I used 2x4’s with a break in between.
That reduced the size of the heat pump so there was a slight savings.. The home was supposed to be my parents last home but Pop sold it 2 years later and moved to the beach so I had a place to vacation so I wasn’t too disappointed

 

[Harvey]

I actually built a house with 2x10 walls. I used 2x4’s with a break in between.

This is pretty expensive from what I have seen.

With a layer on the outside how do you keep the mice from chewing it?

Spray foam is great but can be a nightmare if done incorrectly.

There’s some Youtube videos of jobs that were done below the proper curing temperature.

If you have any roof leaks the rot can develop and can travel underneath the shingles.

Not sure I get what you are saying here.

 

[Sbob]

This is pretty expensive from what I have seen.

With a layer on the outside how do you keep the mice from chewing it?


Not sure I get what you are saying here.

Yes it was expensive, all the windows needed custom extension jambs, Mom liked the deep windowsills for her plants.

I didn’t use OSB for the exterior sheeting ( used to fasten to the wall studs before vinyl siding on the outside) I used plywood. Windows get installed and then a layer of rigid insulation is added before vinyl siding goes on. I don’t think mice like this stuff.

A two part spay foam requires a chemical reaction to work properly and needs a minimum application temperature. If it’s done below the temperature it has to be removed. Hire an experienced contractor.

 

[sig]

I would spray entire home if it was me. You do run the risk of it being to tight. Would spray roof and foundation walls at a minimum. runtal radiators are in and they look great. you wont change the plans, but your wife probably will.

 

[Harvey]

Runtals are in the plan thanks to you bro. Will see if I can afford them.

 

[D.B. Cooper]

Seems like foam for the ceiling/roof and regular insulation for the walls is a good compromise to me: efficiency, breathability, vocs and cost.

Yep. Our upper floor is all spray foam. A little too well insulated as we get condensation on the windows.....and the interior of the windows is stained wood. The basement is batts. I'm told the spray foam adds some structural support, although I don't know how much. There is also open- and closed-cell spray foam. I'm not sure the difference.

Out of curiosity, what type of foundation, Harv?

 

[Harvey]

Out of curiosity, what type of foundation, Harv?

Poured cement.

So you recommend not doing full foam?

 

[Milo Maltbie]

I've been out of small buildings for a long time, but I'm surprised that 2X6 framing is the code now. The money would be better spent on a better air barrier and continuous thermal insulation outside the structural components. Insulating between the studs is like wearing a sweater stuffed between your ribs. It's just not gonna be completely effective.

Also better windows installed correctly. My condo was built when it was supposed to be so airtight you couldn't flush a toilet without opening a window, but if you sit by a window you feel a breeze if there's any wind outside at all. No one was paying attention when those windows were installed. A mason once told me "never strike a joint the client can't see" and that attitude applies to all building trades.

mm

 

[Sbob]

Poured cement.

So you recommend not doing full foam?

Your can foam the outside of the foundation and under the slab too.

Making a house tight in my area can create a Radon problem.
Putting foam under the slab would prevent that problem. I wish I would have done that.

If your home is too tight a fresh air ventilation system can be installed but now you’re using energy to move air. I’m thinking crack a window until it gets too cold or hot outside.