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1 Answer

Bathroom ceiling

I am going to be installing t&g pine (sealed all 4 sides and ends) on a bathroom ceiling. The ceiling is below an unvented roof and conditioned attic space (8" closed cell foam in rafter bays). Climate zone 8.

I want to know if I should install the t&g directly to the framing members or to put up drywall first. I already have an ignition barrier over the foam. Will drywall just be a surface for mold and mildew? I have a Panasonic whisper green vent fan and a window in this 72sq ft bathroom.


Asked By Jon Patrick | Feb 6 16
25 Answers

Final advice on insulating a basement correctly

Hi I’ve read the great articles here on how to insulate the basement correctly - I just want to make sure I'm going to do the work right and I trust the folks at GBA


• Southern exposure home – south has 2x6 pt walls with a few windows and doors (basement level)
• North has an 8ft concrete wall that behaves like a huge cooler – it also has a 24inch 2x6 pt wall on top of that, so the basement ceiling height is 10ft.
• In the worst heat in summer 90 degrees + the basement is extremely cool with the windows closed – just like air conditioning

Asked By Robert Metelsky | Aug 4 15
12 Answers

New roof, new skylights, new condensation... and not a lot of answers. Any help?

Hey everyone. I don't normally post to anything but I'm at the end of my rope and not sure which experts I can trust so looking for some extra opinions before I go and do nothing or start making tons of holes in my roof.

Asked By S. B. | Jan 24 16
0 Answers

closed or open cell

you have helped me before. i have decided to do a spray foam insulation. the building is pole barn type build [wood] covered in sheet metal. it has a concrete floor,insul garage door an it will have a/c only, it also is located in central fla. i,ve had 3 different contractors with 3 diff ways of doing it. one is closed cell on walls an roof an he said 1/12 "" is all thats needed. he had the best price [ still not cheap]. the next guy wanted to close cell the roof an open cell the walls.

Asked By bill metzger | Jan 31 16
4 Answers

Can you install batt insulation in the cavity of a double stud wall?

Hi, I'm building a cabin in upstate NY and trying to achieve an R-50+ wall. I want build a double stud wall assembly with Roxul Comfortbatt. I'd like to install a continuous layer of batt at the wall cavity (in addition to between the studs themselves). The manufacturer advised against this. They said the batts won't stay in place unless secured between two studs. I've been seeing examples online however, that suggest you can do this. They show double stud wall, cavity filled with dense packed cellulose or batt - unless I'm misunderstanding. Can anyone advise on this? Thanks in advance.

Asked By Nora Meehan | Jan 30 16
22 Answers

Off-grid PV solar for domestic HW

I am planning a small off-grid home and would like to send all surplus energy from the 4.8 kw solar array to a standard electric water heater, probably of 60 or 80 gallon capacity. In effect, it would serve as an additional "battery" once the main battery bank is fully charged. Does anyone have any suggestions or experience on how this might be done in a fairly simple and reliable fashion?

Asked By Peeter Vihvelin | Feb 22 13
7 Answers

Insulation plan for bonus room above garage

I am in MN(zone 6), working on my new construction.
It has an attached garage with a bonus room above it. I don't plan on finishing it right away but would like to plan how I am going to insulate it.
I have sheathed the roof deck with 7/16" zip sheathing. It will be covered with Cedar shakes. I have already roofed almost half of the house and am slowly making my way towards the garage.
I am considering both vented and unvented assemblies.

One of the possibilities is:

Cedar shakes with 30 lb felt paper interlayed
1 1/2" above deck ventilation
Zip sheathing

Asked By asim majeed | Jan 26 16
3 Answers

Wall systems decision

I am designing and home in the outskirts of Santa Fe, NM (climate zone 5B / elevation 6800 ft.).
I am interested in energy efficiency, low maintenance and overall best choice for this climate.
(note: we are planning to use geo-exchange heating and cooling + PV's to minimize energy costs as the site will only have electrical and propane fuel sources)
We all know pretty well the pros and cons of double wall frame construction for this area.

Asked By Abelardo Ruiz | Jan 25 16
15 Answers

Finishing the attic space - Best insulation plan?


I'm planning to convert my unfinished attic space into an entertainment room. It has a cathedral ceiling, knee walls and flat ceiling. I'm looking at fiberglass:

The current plan is:

Cathedral (2x10) - Vent baffles with R38 faced fiberglass batts
Flat Ceiling (2x8) - R-49 faced fiberglass batts
Exterior Walls (2x4) - R15 faced fiberglass batts
Kneewalls (2x4) - Roxul Safe n Sound (to keep noises from entering bedrooms below)

The attached plan shows it better.

Asked By Jason McCoy | Jan 25 16
25 Answers

Our builder insulated our cathedral ceilings with dense pack insulation. Now we are having condensation and mildew problems.

We have contacted a local roofing company and it proposes to remove our shingles and sheeting and then remove all the insulation. They also propose removing siding where necessary. Cost: $140,000. Is there another solution?

Asked By James More | Jan 22 16
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