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3 Answers

Crawl space liner for the dirt floor or closed-cell spray foam?

I live in upstate NY and I have a 4 1/2' high crawl space under my house with a dirt floor. I was told to insulate the walls with 3" of closed spray foam and use a crawl space liner on the floor. Another contractor said I could use 2" of closed spray foam on the walls and floor. Yet, another said 3" should be used. Which is correct?
Thank you.

In Energy efficiency and durability | Asked By Kathleen Stewart | Nov 16 16
3 Answers

Spray foam for interior walls with external siding and rigid foam


My house has existing vinyl siding with 1" foam (not sure what kind yet) installed over the old clapboards and then the vinyl. Inside, there is no insulation in the 2x4 stud walls covered with crappy drywall. This is a coastal house in Zone 5 (Massachusetts).

In Energy efficiency and durability | Asked By david flinn | Nov 16 16
2 Answers

What are the best basement windows?

We have three standard size basement windows to replace. I was looking at the hopper windows. Any other recommendations? Thx in advance!

In General questions | Asked By Masb H | Nov 16 16
6 Answers

Installing stone veneer over 2-inch rigid insulation

We live in climate zone 5A and we unfortunately purchased a log home that only has 3.5" pine walls with no insulation (we thought there was insulation at the time of purchase per the manufacturers website). Anyway, we want to install 2" rigid insulation on the outside of the log walls and use stone veneer. I am trying to understand the wall section though. My thought is:

3.5" pine wall
2" rigid insulation
metal screen with scratch coat
stone veneer

In Energy efficiency and durability | Asked By Nicole Bennati | Nov 1 16
2 Answers

Sloped aluminum sill over exterior mineral wool

I just wanted to see if anyone had a good suggestion for an exterior sloped sill for our windows. I recognize we probably made a major mistake in installing these, as we should have either left a larger space below the windows or set them an inch or more out from the plane of the sheathing. As it stands, they are flush with the sheathing. We are placing 2 layers of 1.5 inch mineral wool plus vertical wooden furring strips for a rain screen. My contractors plan was to use white aluminum to make a sloped sill to divert water from going behind the mineral wool.

In Green building techniques | Asked By Brian W | Nov 14 16
1 Answer

Comfort Board 80 vs 110 - density worth extra cost?

For our upcoming house build using 4" of rigid mineral wool we have been quoted for both Roxul comfort board 80 and 110. Over the top of this we will install 2x4 furring and cedar siding.

The 110 has a compressive strength of 1120 PSF at 10% deflection, the 80 is only 439 PSF at 10%, using the 110 will simplify the installation of furring as it will compress less, but I don’t know that the furring installation sub would price their install any differently between the two products. (Furring install not by insulation contractor).

In Green products and materials | Asked By Chris Armstrong | Nov 16 16
5 Answers

Is closed cell spray foam between rafters in an old house a good idea?

To all, but especially to Dana Dorsett and Martin Holladay,

In GBA Pro help | Asked By Rebekah Haworth | Nov 15 16
18 Answers

Partially finished basement question

I have received advice here in the past and read through all of the articles for finishing a basement. I live in Minneapolis and I had planned on using a 6 mil poly, 1'' EPS, and 3/4 t&g plywood for the floor before adding the finished floor.

But..as I got to plan it, I was thinking about the implications of finishing this area as it is only a partial finish of the basement. I am adding a room to a finished space that has carpet on concrete. I do run the dehumidifier all summer to keep it <50% RH.

In General questions | Asked By Jay Johnson | Nov 9 16
24 Answers

Net zero construction in Yakima, WA — Climate Zone 5B

Hi there,

I have been a frequent reader of this website over the last couple years and didn't see an article that addressed a few questions I have run into when attempting to design and build a net zero home in Yakima WA (climate zone 5B).

In Energy efficiency and durability | Asked By Joshua Greisen | Nov 10 16
3 Answers

Quite a complicated situation for basement refinishing next to a crawl space


I've got quite a complicated situation in my basement that I've been struggling with for years. The time has come to get everything finished up, so I need to make some critical decisions. For reference, I live in Atlanta, GA.

My home is a 1950's ranch that was on a huge crawlspace. 60% of the crawl space had been "finished" and the other 40% was dirt floor with shower-pan liner laid all over it but not sealed (no idea). The crawlspace vents had been sealed, but no fresh air was introduced. As you can imagine, this created huge issues down there I had to remedy first.

In General questions | Asked By Chris Kosiba | Nov 14 16
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