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1 Answer


Editor's note: This is the second posting by Michael Schumacher on this topic. GBA likes to have all follow-up questions on the same thread, so the contents of Michael Schumacher's second post have been moved to the original thread. Here is the link to the original thread: My project is insulating a 54 x 72 x14 pole barn in southwest Michigan.

Asked By Michael Schumacher | Aug 27 15
15 Answers

Humidity control

I operate a facility where humidity control is very hard. The building is 6 yrs old, built well, but cant control the humidity. We have resealed return duct, replaced tstats, added attic exhaust fans, etc. But still the building humidity matches the outdoors as fast as it changes. We try to keep the building 72f and it feels like you can't breath and hot. Mildew forms. We keep the building 68f you can breath, but freeze and smells like a basement, and mildew forms. All exhaust fans are working, and ceiling fans are on.

Asked By clark jones | Aug 24 15
1 Answer

Furring strips or another layer of sheathing over foam?

I am in the process of framing a house 2x6, 24”oc. The house will be sheathed and taped with the Zip system and 2-1” layers of rigid foam (staggered seams and taped). Over top of the foam, I planned on using 1x4 or ripping down ¾” ply for furring strips to both hold the foam and attach the vinyl siding too.

Asked By Brian McDonald | Aug 27 15
7 Answers

Zola Windows


Asked By william dempsey | Aug 25 15
1 Answer

Roof ventilation ideas

I'm trying to add attic ventilation for my whole house fan, as the manufacturer states that I need a total of 4.4 sq. ft. of free air. I currently have gable vents, but they're located right above a window and the attic air gets sucked right back into the house (even when the window is closed, to some degree, and I'd like to open that window anyway). So I'm thinking of sealing off the gable vents and getting all the ventilation from the roof.

Asked By Robert Shelton | Aug 26 15
5 Answers

Exterior door details with 4" thick foam walls

I've read plenty of articles on Dudley boxes and setting innie and outie windows, but doors are a whole different animal mainly due to the swing and bottom. The sides and top are basically the same details as a window to my understanding. It may be possible there is a manufacturer that makes door settings this wide that are affordable? The wood on all of the original doors is rotting because they were set 3" off the finished grade and got wet always. The foam will be 4" in areas and the walls are either 2x4 or 2x6 depending on the area of the house.

Some of my questions and concerns are:

Asked By Michael McArdle | Jun 3 15
14 Answers

Using a 'whole house like' fan for cooling

Have read your info on Whole House Fans, grew up with one and would like to use the concept. Would you comment and correct my thinking?

Asked By Ron Kliesch | Aug 25 15
3 Answers

Rim joist foam and termites

I'm not sure if this would fit better 'Energy Efficiency and Durability' category, but I have a few questions about using foam to insulate rim joists. From an air-sealing and thermal performance perspective foam seems the clear choice. I've read Martin's FHB article and spray foam and cut-and-cobble approaches make sense.

Asked By Jeffrey S | Aug 24 15
2 Answers

What is your opinion of the CERV HRV system?

Looking to add an HRV to a new home plan, 2500 sq.ft.

Concerned with humidity levels in Massachusetts. Very humid summer. Dryer winter. House will be close to net zero.

Asked By Joseph Isherwood | Aug 26 15
4 Answers

Advice needed to insulate an existing block wall from the exterior

The local parish hall has a 40' x 44' addition with exterior walls of 8" concrete block and a bow truss roof/ceiling that was built in the 60's. On the interior, there is no additional wall build-out or insulation, just exposed block. We are planning on insulating the exterior walls and adding blown in cellulose to the existing fiberglass roof insulation after air sealing all penetrations.

Asked By Jon Michael Wyman | Aug 25 15
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