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15 Answers

Frost wall foundation details for stone and siding construction

I am planning a slab on grade build (24"X8" footings, 4' deep, with 4'6" frost walls). I am having issues with the location of all the sub components on the frost wall width, specifically on the stone detail wall (front wall only).

In GBA Pro help | Asked By Mai Tai | Jun 18 17
6 Answers

Considering ERV pre-heating options (maybe cooling too)

Hello from a long-time lurker but first-time poster!

It's hard to express how helpful and inspiring this website is to a non-professional like myself. I'm particularly taken by the generosity of spirit shown by all who contribute thoughts, ideas, and experience with such passion. It seems that everyone wants to do their part to help heal our hurting planet--buildings are a huge part. Thank you, thank you.

Okay...end of speech. Some details about our build plans.

In Mechanicals | Asked By Richard Hoenich | Jun 24 17
28 Answers

Exterior foam and fires

There has been a fire that gutted a high rise apartment building in London. It appears to have spread through the foam-filled exterior cladding panels. Similar fires have occurred in tall buildings in Dubai.

While the situations aren't directly analogous, I wonder if there are any lesson here for builders contemplating the use of exterior foam?


In General questions | Asked By Malcolm Taylor | Jun 14 17
4 Answers

How much of a gap should I allow in exterior plywood sheathing to allow for expansion and contraction?

Thank you to everyone who has posted and responded to related questions and gotten me to the point where I can more or less ask this question in an intelligible manner.

In Green building techniques | Asked By Joel Fyke | Jun 24 17
10 Answers

How does someone cancel subscription when there seems to be no way out??

Could someone guide me in the cancellation of membership? it doesn't seem like it is possible to do so.

Thank you

In General questions | Asked By James Someone | May 27 17
3 Answers

Dense-pack retrofit cellulose insulation for basement walls?

I recently had an energy audit done existing 1958-built tri-level in climate zone 5 (Ann Arbor MI). Looking for advice from the GBA experts to sanity-check some of the recommendations before making decisions; I'll try to keep it to one question per post. One recommendation was to add dense-pack cellulose into the existing above-grade and below-grade (finished) walls.

In Energy efficiency and durability | Asked By Phil Ray | Jun 22 17
3 Answers

Interior rigid foam for ceiling

I have been working on a well insulated house in climate zone 3. We installed 38' trusses for the roof, and I have been concerned by some things I have read about the potential for truss uplift, especially with such wide trusses. Right now the trusses look great, and are very flat and level.

In Energy efficiency and durability | Asked By Jason Whitacre | Jun 22 17
4 Answers

Anyone seen nail corrosion from Roxul?

I'm slowly building my home home and last year I fell for a great price on roxul comfortbatt. I bought what I thought I needed and stacked it in the basement of the dried in house. 8 months later I moved the roxul and was surprised to notice white carrosion and rust on the galvanized Hitachi ringshank nails I used to attach studs to an interior wall sill plate. Nails show carrosion only where I stacked the roxul and no where else in the entire house. I recently learned that roxul has formaldehyde and worry that the off gassing through the plastic wrap is the culprit.

In Green products and materials | Asked By Ryan Williamson | Jun 22 17
3 Answers

Another wall — Is this a good idea?

I recently visited a home zone 6 with this wall detail.

It appears to be an interesting way to achieve R27 or so between studs, but is this a good idea?


In General questions | Asked By Greg Smith | Jun 23 17
2 Answers

Conditioned or unconditioned crawl with mini-splits

I am looking at putting a mini-split into a new home but can not seem to find an answer on how or if I should condition my crawlspace. I know crawls aren't the best route but I don't have the extra $17k to do a basement and a slab isn't an option. So can I build the crawl as a conditioned space without the hvac runs keeping it climate controlled or how should I go about this? I'm willing to put another head in the crawl if that's what needs to be done to make it work.

In Green building techniques | Asked By DG Builder | Jun 23 17
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