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36 Answers

How do I figure out how much solar energy for emergency power?

Hi all,

We have a new house that is all electric. For efficiency, we did not include any fireplaces. This leaves us vulnerable in the event of a power outage during a bad winter. We live in Central KY, so the winters here are usually not too bad, but we do have times where the temps get below freezing for extended periods of time.

We built the home with lots of insulation, so we are able to heat in comfortably with mini splits. We also have a HPWH, so our hot water demands are hopefully low.

Asked By Clay Whitenack | Jan 29 18
7 Answers

slumping of siding from nailing through rigid foam

Thanks for any assistance you can provide.

I am wanting to add additional insulation on the outside of our home. We are in zone 6. Our current walls are 2x6, 24 inch on center with 6 inches of fiberglass insulation, 7/16th OSB with tyvek. We have lived with cedar siding for 30 years and are now wanting to remove the siding and windows. Replace the windows and us LP siding.

Asked By user-7005676 | Mar 20 18
3 Answers

Tips for obtaining recycled scrap insulating board?

I was able to obtain a truckoad from a roofing company several years ago, but now I'm having trouble sourcing it.

Any hints from the experts? I'm in North Texas.

Asked By Lynda Robertson | Mar 21 18
5 Answers

No basement, want no interior VOCs, looking for low cost exterior climate control for paints, caulking and their ilk

I have nearly finished construction of our slab-on-grade house in zone 5 MA.

We have neither a basement, an attic nor garage. All the interior space shares the same air, with a tiny utility room. Interior air quality is important -- the house is all pine and cement. No plywood, no mdf, no chipboard, no OSB; essentially, no glues or resins. No combustion equipment .. all electric. Very few plastics, no carpets, no paint. What we breathe matters.

Asked By Kenneth Gartner | Mar 23 18
3 Answers

Necessity of smart vapor retarder in Tiny House on Wheels in Zone 4A?

GBA community,

Asked By Cam Kerr | Mar 23 18
2 Answers

Best way to insulate an existing pole barn that has metal siding and no wrb?

I have read many versions of this question (as well as many answers) on your site, and at this point I am looking for the most current responses and solutions to this age old problem. I am well aware of the inherent pitfalls associated with pole buildings but it is what i have and i am hoping to make the best of it.

Asked By Darryle Mendes | Mar 21 18
4 Answers

Polyiso Interior Insulation in Old Barn

I am starting on the second floor remodel of a 19th c. barn, and I'm considering using polyiso panels on the interior side. I've never used rigid and non-rigid insulation in conjunction, and I have a few questions.

The Basics:

This will be a storage space and workroom. The barn is in Maine. The barn exterior is original horizontal siding (which I may be replacing but not until summer) over original vertical 1x sheathing (with some gaps). This is attached directly to the frame of the barn, which is open on the inside and roughly 5" deep.

My Plan:

Asked By ThreeBirdFarm | Mar 22 18
16 Answers

Should I vent a cathedral truss with a metal roof and foam insulation?

Using 2 layers of 2 “ Poly foam under the roof strapping then 2” air space and 1 more 2” Poly going across the top chord of truss to eliminate thermal bridging.

Asked By User-7034059 | Mar 10 18
7 Answers

Open cell spray foam under roof deck

A couple years ago we converted our vented attic to an unvented/conditioned attic with open cell spray foam applied under the plywood roof deck. We even installed an HVAC vent in the attic to keep the RH in the attic similar to the rest of the house. So far everything seems fine but I've recently read about issues with open cell under roof decks, including one article on this website. I live in climate zone 4, asphalt roof over plywood deck. Should I be concerned about having a wet roof deck?

Asked By Michael Mohr | Feb 7 17
6 Answers

Basement vapour barrier


Asked By user-6994354 | Feb 17 18
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