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3 Answers

Use scrap polyiso for inground gutters?

I have bunch of scrap 1 1/2" fiberglass-faced roofing polyiso left over from basement insulation project. Next large project I will be working on is fixing grading issues around the perimeter of the house, removing all the bushes right next to foundation, and putting down washed p-stone (likely). I have read before on GBA about those inground insulation "skirts", but there XPS or EPS is recommended with EPDM on top. Would it be bad to just use scrap polyiso under EPDM?

In GBA Pro help | Asked By Apollo S | Apr 8 15
13 Answers

R-25 rigid insulated roof deck with cold metal roof above question

Zone 6 remodel in design phase. If anyone has links to similar design pics/blog building a cold/insulated roof it would be much appreciated.
Insulating roof deck to R-25 or greater with combo of reclaimed rigid foam.
I would like to then create a vent space (my question), followed by Plywood, then metal roofing.
What is the best way to create the vent space and how deep does it need to be (roof pitch varies 7 to 9).
is a criss cross pattern of 1x3 screwed to rafters followed by another horizontal to the ridge the best approach?

In GBA Pro help | Asked By Dirk Gently | Apr 3 15
3 Answers

Turning my Zone 5 attic into conditioned space

So have been scouring for iso to do my basement walls and needed only 40 sheets, but Ive come across a guy who has 100 sheets and needs to get rid of them all at a crazy price.
So my question is can I use this 3' iso on the underside of my rafters to bring my attic into a conditioned space.
The attic insulation is already at R60 (R38 batts and the rest blown in cellulose) but I thought if I have all this left over Iso I may as well use it in the roof and give my central air a break.

In Energy efficiency and durability | Asked By Darren Finch | Apr 8 15
32 Answers

I am overwhelmed with the wall cavity options and need advice

After researching for the last few months on this website, buildingscience.com, and PHIUS.org I am just overwhelmed...buy maybe under informed. I am an owner/builder (former construction project manager...mainly responsible for foundation and electric work then) and this will be my second house. Most of the case studies and articles I have read are about homes in climate zones far more extreme than what we typically have in TN.

In Energy efficiency and durability | Asked By Andrew Bennett | Mar 4 15
4 Answers

Double stud wall with timber ceiling

I am designing and building a double-stud wall, single story house on a slab-on-grade foundation with a frost wall. As a dedicated timber framer, I have tried to hold on to some aspect of that approach while acknowledging that it adds cost and complications with air-sealing, etc. I devised a method where the outer wall supports the roof (cathedral) and the inner wall supports the ceiling assembly. My concerns are with the inner wall bearing the load from the floor to the edge of the slab.

In Green building techniques | Asked By Caleb Creaven | Apr 8 15
3 Answers

Insulating radon-mitigated crawlspace floor

I finally have solve the radon problem in my house and sitting pretty with 0.8 average. Also very happy that formerly "unvented yet might as well be", dirty, and damp space is now so clean, I only walk in my socks there.

That all said, walls I am insulating with polyiso (two layers of 1.5"), rim joist I am going to spray with closed cell, when space becomes warm enough. But it leaves the floor uninsulated.

In GBA Pro help | Asked By Apollo S | Apr 8 15
5 Answers

Please review this window retrofit and provide feedback

Can I get feed back if the pictures tell the story of a good window install.


In General questions | Asked By Alexander Sanita | Apr 8 15
8 Answers

I need assistance with window/door install with 4" foam

I am looking for some direction on installing windows and doors. I have 4" exterior EPS on a 2x6 walls

The current plan is to build 5/8" plywood boxes (I believe they are called Dewey boxes) to get the nail fin of the window to the same plane as the furring strips that the foam and the siding will be attached to.
I am sure its been covered but searching Dewey box got me 0 results so I wonder if someone could point me in the right direction?

Tim (Kenora ON Canada zone 7)

In Green building techniques | Asked By tim brown | Mar 28 15
14 Answers

Using recycled rigid foam

I'm considering using rigid foam on the exterior of my roof. Cost is of course a big concern with this approach. I'm found sites online that sell recycled rigid foam. Apparently, it is often recovered from commercial buildings and shipping containers.

I read one post on the site that caution against using foam that had been degrade during freeze/thaw cycles. Are there any other issues to look out for? Have anyone tried the "recycled" approach? Is there a reputable source for material? Any lessons learned you folks could share would be greatly appreciated.

In Green products and materials | Asked By Steven Knapp | May 10 13
3 Answers

Is there a humidity calculator out there?

I live in a leaky house, the inside humidity tracks the outdoor humidity with a lag and temperature adjusted, but i want to be able to input an outdoor temp and humidity and calculate what the indoor humidity will eventually become at 20ºC (theoretically of course).

Basically i want to know what the resulting humidity would be at an input temp and humidity if that air was raised to 20C

I know the outdoor will eventually change before the indoor catches up but it would be useful to me.

In General questions | Asked By Alan B | Mar 15 15
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