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7 Answers

Insulation — basement rim joist


I want to insulate the rim joists of an old home. I have caulked the joists due to openings in the wood from age. I don't want to use rigid board/spray foam. I was going to use batt insulation (unfinished basement), but wonder if there is something that is not toxic or contains fiberglass, etc.. something i can cut and shove in the openings and just leave it there. I don't plan on using any plastic, vapor barriers, etc..


Asked By Dave Mac | Sep 23 14
11 Answers

Has anyone used the shim screws and EPDM gaskets made by Conservation Technology for installing windows?

Is the technique easy to learn? How many shims crews would you use on a window?

Asked By David A Flannery | Aug 18 14
0 Answers

What is the best detail at a slab on grade pour through to insulate the slab?

Or is it just a weak point that can't be avoided?
I have 2" of rigid insulation under the slab and 1" at the L block.

Asked By David A Flannery | Sep 23 14
2 Answers

Insulation for dormer with thinner studs

I am in the process of building a small cabin in Climate zone 7-8. All the walls are 2x6 and I am planning on using Roxul to fill the stud bays. Exterior has no foam just 1/2 plywood and Tyvek. I will be installing a rainscreen and using some sort of cement board siding.

Asked By Andrew David | Sep 23 14
5 Answers

Dryer ducting — materials requirements

Hi all,

I've been finding so much mixed information regarding this all over the net. Some places specify only rigid galvanized steel is approved for in wall and attic, other places I find aluminum or galvanized is approved.

Asked By Joe G | Sep 22 14
1 Answer

With DriCore, why is the 1/4 inch gap around the perimeter necessary?

Just watched the install guide for Dricore. I'm finishing my basement. Right now it's bare concrete. It says in the video to leave a 1/4 inch gap around the perimeter. However it doesn't give a reason why. Here is what I was originally planning on doing. I have true foam type two rigid adhered to the concrete walls with seams taped and spray foam to fill in the corners and bigger gaps. Next the plan was the install the dricore tight against the foam. exterior walls are to be studded up on top of the dricore 24' oc with r20 batts between the studs.

Asked By Mark McKenzie | Sep 23 14
86 Answers

The differences between mass and insulation

The "I installed more attic insulation and now my AC runs more" thread got me thinking about the mass effect a bit.

Asked By Nathaniel G | Sep 15 14
2 Answers

French drain


I had a question about the gap at the wall with the french drain. We are concerned about radon, and if we do not anticipate any water entering the basement again after install of the drain, can we not have this gap at the wall?
Can this simply be cemented over? Contractor said it could.

Asked By Dave Mac | Sep 23 14
2 Answers

Tyroc subfloor

Hi would like opinion on Tyroc subfloor for use in basement and if it is better than some of the others subfloors on the market Thanks

Asked By Brad D | Sep 21 14
14 Answers

Insulated slab detail "problem"

We are to build a Passive House in PA, and have "borrowed" a technique from another PH in Virginia, where part of a typical EPS under slab was substituted with a layer of perlite bags placed over just 4'' of EPS. I believe it also allowed us to reduce the slab thickness to 4'' (in the center).

Asked By Lucyna de Barbaro | Aug 22 14
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