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7 Answers

Is my uninsulated garage making my house hot?

I have an attached uninsulated garage with its own attic, is that why it is so hot in my Austin, TX house?

In Energy efficiency and durability | Asked By K C | Jul 16 15
4 Answers

Pex plumbing retrofit + crawlspace insulation

Hi, I live in an older (1920's?) single story 1200 sf wood frame house on a post & pier foundation; small rural town in far northern coastal CA. The water table is high in the winter & indeed can have standing water of several inches around and under the house for short periods of time in non-drought years (and, yes, I've considered a sump pump, but nowhere to pump the water to that wouldn't flow back or, if not, compromise my neighbors property/dwellings).

In Green building techniques | Asked By Barbara Keating | Aug 2 15
1 Answer

Open-cell foam in an old home

We just purchased an 100+ yr old home that has been updated with new plumbing, wiring, and HVac units. There is a new metal roof on the home. There is an area over one of the bedrooms upstairs that is inaccessible for insulation. The room is hotter than the others. We can get some insulation blown in the area. We are trying to decide between open cell foam for the remaining attic or more regular fiberglass insulation. I've read a lot about open cell foam. My concerns are:
1) the area that can't be accessed. Will this let in moisture and cause a problem

In General questions | Asked By Ashlee Melendez | Aug 2 15
4 Answers

Minimal maintenance grout

Hello All,

Tried searching the archives but couldn't find anything. Looking to get some info on grout that requires minimal maintenance.

My tile guy uses "TEC grout" but I have heard good things about " The Power Grout" by AccuColorEFX which I think is Epoxy mixed or something like that.

Possible for GBA experts give us their expert feedback?



In General questions | Asked By Beenash Khan | Aug 1 15
10 Answers

Is it OK for a basement floor slab on slab edge on only 3 sides?

I am having a new house built and when I looked at the foundation there was a floor slab edge only on 3 sides and when I called the general contractor he told me the concrete contractor had already poured the floor and said it was all fine. the rest of the concrete work looks fine, but missing the slab edge on one side worries me and I don't know what to do???

In General questions | Asked By Steve May | Jul 30 15
10 Answers

Anybody familiar with British Columbia building codes?

I am building a home in BC, and plan to use Lunos e2 for my HRV. There is a lot of stuff about ventilation and HRV in the latest code revision (Dec 2014, I believe). Is there, by any chance, anybody out there familiar with the BC codes that can tell me if I am going to experience issues trying to use the Lunos fans?

A couple things that I am concerned about (off the top of my head).

In Building Code Questions | Asked By Stephen Youngquist | Jul 29 15
2 Answers

What vapor barrier should be used with interior / exterior insulation?

I'm probably looking to build a house in Kentucky, IECC Zone 4 (not marine.) My general goal is durable, economical, energy efficiency. I'm currently thinking cellulose filled wall cavities with exterior foam or mineral wool sufficient to keep the sheathing warm. The structure will be air conditioned.

What sort of vapor barrier is called for, if any? I could imagine a fully breathable structure with Roxul, or a tightly sealed barrier under foam. Are there particular merits to any solution?

(I'm also interested in general comments on this approach.)

Thanks for the advice,


In Energy efficiency and durability | Asked By John Ranson | Aug 1 15
13 Answers

Household humidity

Lots of numbers. Thermostat reads 52% humidity, HRV control reads 49% humidity. The Hobo reads 56.5% relative humidity. The sling psychrometer has wet bulb 66, dry 72, which is 76% relative humidity. So how humid is this place?

In General questions | Asked By Walter Gayeski | Jul 30 15
16 Answers

Air Sealing - Tape, Sealant?

I am looking at the articles here about air sealing and most of them provide information such as where to seal but the products are not so easily determined. I am planning on taping either the OSB Seams before house wrap with 3M All Weather tape - or possibly only taping the house wrap seams. (as long as I get the right tape that doesn't allow problems with taped horizontal seams)

In Green products and materials | Asked By Nicholas C | Jul 29 15
2 Answers

Steel Quonset hut — 1 hour fire rating?


In Building Code Questions | Asked By J Choi | Jul 31 15
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