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3 Answers

Saw this site form Dan Houlihan of HeatingHelp.
I have a 1917 home in Detroit, Mich that I am renovating. It has a American Thatch" or "Smurf" cedar shingle roof with an open stringer deck underneath. These must be vented on the underside to allow the shingles to dry. Currently there is no insulation. The floor that the roof encloses is livable space, but I will demo all of the plaster walls for insulation access. I have 8" rafters

Asked By Mark Reynolds | Apr 10 14
1 Answer


I just installed a new slab. Slab is approx 5" thick, and was set up as follows. We dug trenches and laid drain pipes in gravel, fabric wrapped, etc. On top of that another layer of crushed stone, 2" insulation and then a fully waterproof layer (Grace Pre-Pruf). On top of that poured the 5" slab.

Plan is to put down pressure treated sleepers, with t&g plywood on top and then put an engineered wood floor on top of that.

Asked By R W | Apr 11 14
57 Answers

I am currently looking to put forced air heating and air conditioning into my house. I am located in Long Island, NY in zone 4a, right on the border of 5a. We recently gutted the entire house down to the studs and we are replacing the whole heating system. We will be using gas heat. The contractor that I think we are going to go with is going to install a furnace in the basement for the basement and ground floor, and a furnace in the attic for the second floor. Well also have a blower in the attic for the air conditioning.

Asked By Kevin Schramm | Sep 3 13
2 Answers


Looking to use Roxul stone wool batts in the ceiling area. Anyone here know about any air quality testing with these batts? Even though it will be behind 1/2" drywall, are there any issues with the fine particles from the batts or any off-gassing?

Asked By Peter L | Mar 31 14
6 Answers

It sounds like the makeup vents are making noise (according to my wife). Could this be due to a dirty filter starving the unit of air? Filter is 5 months old. Thank you

Asked By Kenneth Clement | Apr 9 14
3 Answers

Dear GBA readers,
I'm starting the process of finding a roofer who can add up to 6 inches of insulation on top of the roof. I have an unvented cathedral ceiling in the attic, with rafters filled with mineral wool. I would like to get a clearer picture of what is involved before describing my needs to prospective contractors.

Asked By Hari Kamboji | Apr 10 14
13 Answers

Im redoing my partial basement, to make it all into usable living space, which involves digging out half of it and removing a current half slab to increase headroom, and adding to the foundation/footing as needed. Is there any real reason to pour a slab after this is all done?
I would love input from someone who has put a vapor/water barrier, some foam insulation between 2=4 sleepers, and then used some form of wood flooring that would work for higher humidity situations.

Asked By rob rosen | Apr 5 14
10 Answers

Hi everyone,

Asked By Nicholas Brown | Apr 4 14
6 Answers

I appreciate any help I can get on this: We recently built an energy-efficient greenhouse and the mason just finished building the concrete block raised beds. We need to seal or install a liner inside the raised beds to keep water (from the soil) from leaching through the seams of the concrete and we also need this sealer/liner to be safe for growing edible plants and trees (i.e. not leaching contaminates into our soil). We will mostly be growing fruit trees but plan on growing vegetables as well. Can anyone give us advice one what products would be appropriate?

Asked By Leah Marshquist | Apr 10 14
7 Answers


I am designing a small commercial building for a client in climate zone 5A.
The design has two thermal challenges I am looking to get opinions on. For brevity, I will address only one here.

Asked By Eric Whiting | Apr 10 14
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