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16 Answers

Shortchanged on spray foam

OK - So I began to rip down some of the smelly open cell foam and realized that the foam guy
completely ripped me off with the closed cell that was supposed to be under the open cell. There was supposed to be 2" of closed cell....I'm lucky if there is 3/4.

My question is do I leave the envelope alone and just live with it or do I have someone come in and rip it all out and seek legal action for the removal and for the shortchanging on the closed cell?

I'm supposed to have R-38 in the roof decking. I'm lucky if I have R-24 or R-30 in some areas.

In Green products and materials | Asked By joe k | Jun 19 13
2 Answers

Insulating basement?

hello all, today i wuold lke to ask about insulating my concrete basement walls and the ceiling above it..just to add the foundation has tar on the outside as a water sealer & thats it...i read much about closed cell foam spray..sounds great but in climate zone 6A nyc were begining the fall season and i.m concerned about temperature change. my walls are allready framed with wood 2x4's.. this pevented me from useing poly insulated boards.

In General questions | Asked By jerry pignato | Sep 14 13
13 Answers

Unusual Attic Configuration Leading to Truss Rot

My house was built in 1999 in Michigan (48430) with a somewhat unusual layout in the attic. There are 2 windows in the attic on the east and west ends of the house and between those windows, a section of the attic was floored with OSB and drywalled. Under the OSB floor is poorly done R19 fiberglass (top plate gaps, unsealed penetrations, no even installed in one spot I pulled up, ...). Inside the drywalled area, which was fairly well air sealed from the rest of the attic, are 2 unsealed pulldown attic stairs on the east and west ends of the house.

In Energy efficiency and durability | Asked By Greg Perantoni | Sep 7 13
8 Answers

U-value calculation of glazing on custom windows

In the midst of a micro-cabin SIP build that uses very custom sized windows and doors. The frames have been built and are awaiting the custom-ordered glazing. I've searched all local suppliers of insulated replacement glass and can't find anyone that knows what the u-value is on the units which they sell.
Is it possible that u-value is only tested on completed doors and windows (As I'm being told)?

In Green products and materials | Asked By Al Cobb | Sep 11 13
1 Answer

Efflorescence from stone basement walls and plaster walls

Church is 120 years old, there are windows in the walls in the basement that is cover by pictures and dry walls, the space behind the windows are approx 2 ft deep. size is about 2.5x 4 glass still in windows, wood is rotten, we are getting garden snakes and mice. it rains in the one area in the basement. will be adding an elbow to the drain to direct water from area, walls have cracks, birds building nest in the cracks. efflourescence coming into the wall due to window iron bars water leakage.
Now, I have ideals but I hate to not have good information on what to do.

In Green building techniques | Asked By Sharon Davis-Phillips | Sep 13 13
10 Answers

How to retrofit electrical potlights?

Our house has a more than an average number of pot-lights located in the second level ceiling.
The main floor has over 30, however, the main floor is not a concern at the moment. The pot lights which penetrate the upper floor ceiling into the attic space are rated as IC (insulated ceiling) but are not rated for AT (air-tight). The installation Poly boots was not mandated by our local authority.

In Energy efficiency and durability | Asked By Bob Nickason | Sep 10 13
17 Answers

What are good alternatives for the air barrier when building a cathedral ceiling using tongue and groove instead of gypsum?

I am building a log home in North Georgia (Zone 4) with cathedral ceilings and tongue and groove on the inside. Build up from the inside out will be: Pine tongue and groove/ AIR BARRIER / I-Joist Rafters with R-30 fiberglass insulation between / OSB / Felt / Metal Roof. The structure will be vented with soffit vents and ridge vent and 1” air space over insulation. I read the article “HOW TO BUILD AN INSULATED CATHEDRAL CEILING” from this site and the suggested air barrier was gypsum board between tongue and groove and rafters. Is there a good alternative to gypsum? Poly? Typar?

In Energy efficiency and durability | Asked By Alan Shuman | Jun 8 13
1 Answer

Is an exterior curtain wall retrofit more plausible than removing clapboard siding & installing ply sheathing before rigid foam installation?

The curtain wall retrofit would include placing 2X4's vertically against the clapboard siding spaced 24" on center; then filling the 3.5" cavities with spray foam or cotton batts, followed by installing two layers of 2" polyiso rigid foam panels over. Finally, replace the vinyl siding over the rigid foam.

In Green building techniques | Asked By Anthony Zitelli | Sep 13 13
8 Answers

Conditioned or not? What's the best way to insulate a 1950s home's crawl space?

We have a 1950s home with a small basement and the rest crawl space in Zone 4A. I need to figure out the best way to insulate the crawl space and maybe the basement. The house is heated with propane and cooled with central AC. The walls are block in both spaces. There are no mechanical systems or ducts in the crawl space. The sewer, water and pipes from the propane boiler run through the crawl space. Currently the crawl space is vented, uninsulated and has no vapor barrier.

In Energy efficiency and durability | Asked By Woody McMahon | Sep 10 13
1 Answer

How do I best insulate a house without an attic?

I have been researching the last six months what to do about our roof that needs replacing. We live in the Sacramento Valley, hot days and cool evenings (usually). Our house was built in 1966 and is adobe brick.

In Energy efficiency and durability | Asked By Amber Welsh | Sep 12 13
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