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7 Answers

Closed-cell foam insulation

We own a century home which over the years has sunk into the ground so there is little or no crawl space. In order to insulate the ground floor, I would like to tear out the old oak tongue and groove flooring, cover the subfloor with a vapor barrier and then fasten 2x4s to the subfloor and use closed cell foam to insulate. Does this sound like a feasible plan?
Chuck Pemberton

In Energy efficiency and durability | Asked By Charles Pemberton | Sep 21 16

13 Answers

Strapping screws: to angle or not to angle?

For 4" of XPS, with a 3/8" airspace and 3/4" plywood strapping, is it sufficient to screw in straight, or do I need to screw in at an angle? I've read where both are "recommended". From my small-scale mockups, screwing straight through seems adequate, but I've never done this before so I don't want to screw it up (sorry :P). The screw pattern I'm using comes from the manufacture's data sheet, and it doesn't specify a screw angle.

In Green building techniques | Asked By John P. | Sep 19 16

2 Answers

Is a reflective surface necessary under radiant floor heating?

I have a situation in a house with a full basement where there is radiant heat in the floor joists of the first floor, accessible from the basement.
There are unfaced fiberglass batts in between the joists under the radiant piping. My business partner thinks we should replace the fiberglass with foil faced foam, but I think it's not necessary.
My partner's rationale is that there needs to be a reflective surface and there is none now.

In Mechanicals | Asked By Josh Engle | Sep 22 16

3 Answers

Should I consider Structured Plumbing in 4500 sq. ft. house?

Hello and thank you for looking at my question. I hope someone can explain this to me in laymen's terms.

In GBA Pro help | Asked By Cherylann Schieber | Sep 19 16

4 Answers

What is your current opinion on the use of spray foam insulation in the home of a chemically sensitive person?

Thank you so much!

In Green building techniques | Asked By Lu Hawkins | Sep 20 16

40 Answers

North Idaho ranch house design

Our house will be around 1800 sq ft with a 600 sq ft attached garage. In northern Idaho, zone 6.

The plan is to build slab on grade due to water table issues in my subdivision.
Heat would be hydronic in floor heat. High efficiency natural gas boiler which would both supply hot water to floor and heat domestic hot water. Looking forward to no forced air noise or dust. We have Natural Gas service at street.

In Green building techniques | Asked By Steve Wolfe | Sep 15 16

21 Answers

Can kneewall polyiso boards be left exposed on the attic side?

In General questions | Asked By John Sean | Sep 16 16

5 Answers

Balancing HRV-- custom design

So I built in my own HRV and retrofitted it into the house.

I notice most of the literature says I need to sample the mean air speed in a straight section of duct not near a bend or a change in air speed (silencer). I did a combo of the Zehnder tubes and a Fantech HRV. So I have done a few custom things that do not facilitate balancing the system in a standard way.

In GBA Pro help | Asked By frank castle | Sep 18 16

18 Answers

Why does my house SUCK?

It appears that most are concerned with proper ventilation considering the tightly built homes of today. I have a very severe flooring problem that I believe to be caused by negative pressure within my home and would like an opportunity to discuss with people more knowledgeable than myself. Allow me to explain a bit about the construction of my home, myself and my problem.

In Mechanicals | Asked By Cole Sumner | Sep 18 16

10 Answers

Exterior (north) stone wall

Hello-
Indianapolis Zone 5a
My own outside weather station reads mid 70% humidity July through October which is 10% higher than Indianapolis historic values.

House is ranch style one story slab on grade. South facing wall is stone on the outside. The wall construction is as follows from outside to inside:
stone (avg 3 inches) - no noticeable air gap or weep holes.
sheathing - not plywood or OSB-- looks like particle board with black facing the inside.
fiberglass batt - removed
3 mil plastic - removed
drywall - removed.

In GBA Pro help | Asked By Edward Kramer | Sep 13 16

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