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8 Answers

Follow up question re: basement subfloor (climate zone 7a)

A couple of weeks ago I asked a variety of questions pertaining to my livable space basement retrofit for a 1974 home in climate zone 7a. Recap: there is no exterior foundation or under slab insulation, etc. No water penetration issues into the interior but part of the basement has shown recurring efflorescence and some spalling in a few places.

Asked By user-6759891 | Feb 24 17
2 Answers

insulating a garage

I am seriously considering converting my garage into a workshop that I want to use year round. It is cement block construction and I would like recommendations on insulating the walls. I will probably drywalling after and then installing shelving etc. Thanks

Asked By JATotter | Feb 26 17
0 Answers

Heating and insulating for a wide interior temperature swing

I'm planning out my garage, which will be mostly for cars and storage. I may install a small mini-split or PTAC to keep the garage above freezing, and to occasionally cool the building if I'm working in it in the summer.

I've got a couple questions:

Is there any green motivation for insulating the building beyond what fits in the stud-bays (2x6 likely), given that I'm letting the temperature swing widely?

Is there any issue with operating a mini-split with a 40F building temperature?

Are there any vapor management concerns for a building that has wide interior temperature swings?

Asked By John Ranson | Feb 26 17
4 Answers

How to insulate a cathedral ceiling from within the rafter bays

I have a zone 7 1840s house-and-a-half style house, with the second floor walls going about 4 ft up, then sloped cathedral ceiling for another 3 ft up, capped by the flat ceiling and a 4' high crawl space attic. Essentially the second floor looks like a rectangle with the upper corners knocked off, and every surface but the top and bottom is exterior facing. So the sloped ceilings are the thickness of the lathe and plaster, the rafters, and the roof.

Asked By Terry Sharpe | Feb 24 17
5 Answers

How to insulate a shipping container home?

I would like to understand how to best insulate a shipping container home. i am thinking of building on a pier system.

Specifically I am wondering about the double sided foil such as Radiant guard that comes in both permeable and vapor barrier. Which do I put on the inside and which goes on the outside. I live in the Seattle area Marine Zone 4-5.

Asked By SirKoda | Feb 24 17
24 Answers

Basement subfloor retrofit insulation options

We recently renovated our 1897 brick workman’s cottage here in Chicago. We’ve done our best to upgrade the energy efficiency of it including insulation upgrades– although based on some of threads, may have made a few not optimal decisions (closed cell soy foam interior – we’re in an historic district so we cannot make any changes to the exterior.). We’re now seeking to tackle our basement floor, specifically insulate it.

Asked By brandon antoniewicz | Nov 30 10
2 Answers

Insulation under monolithic slab

I am located in climate zone 4a, but literally on the border with zone 3. Planning to build a 22'X22' workshop on monolithic slab, with vented attic. For now the building will be insulated to code for a living space, with a double insulated garage door, and rigid insulation on the exterior of the slab foundation. I believe my local codes require a 2 inch termite inspection gap between the top of the slab insulation and the bottom of the siding. I plan to heat it only as needed with radiant electric panels for now

Asked By nssimpso | Feb 24 17
2 Answers

2x4 vs. 2x6 Exterior Framing

I'm planning my new home in Colorado (climate 5b). We have a very limited building envelope, and so wall thickness is of concern - complicated by the fact that my wife is set on using brick veneer.

That said, I'm going back and forth with using 2x4 framing vs. 2x6 and would love any input on disadvantages of the narrower wall. Doesn't seem like a lot, but the additional few inches does help.

Asked By Brad Burch | Feb 24 17
6 Answers

New home wall assembly

I am currently designing a new single-family home in Northern Virginia (Zone 4, Mixed-Humid Climate) and am looking for some feedback to my tentative plans for wall and roof assemblies. I am not trying to build a passive house, just a more durable house. My primarily concern is controlling/managing air and vapor movement.

Walls: 2x6, 24" oc w/ open-cell spray foam insulation in the cavity, ZipSystem R3 sheathing on the exterior and 5/8" drywall foamed to the studs.

Asked By Michael Winn | Feb 11 17
6 Answers

Roof insulation for a West Baltimore row house

I've read some earlier GBA discussions about insulating brick buildings and those with flat roofs, and I'm planning to follow the guidelines I've gathered from those. My question is about the full insulation process for the roof when you use spray foam on the interior side of a flat roof. I recognize that the best advice is to put the insulation on the exterior side on top of the sheathing, but for a variety of reasons, that wasn't possible when I had my roof replaced in the fall.

Asked By Timothy Werner | Feb 20 17
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