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0 Answers

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
9 Answers

best way to fix insulation problem in cathedral ceiling, please help!

i build my chalet about 8 yrs ago and was up in the attic and noticed black water stains (probably mold).
after many days and night researching what was wrong, i believe my issue is insulation and air leakage.
i have called all the insulation and roofing businesses (not many in this area) and each says its the others issue.

this site has been the most informative, but i cant seem to find any article or videos on how to add or change insulation in a cathedral ceiling after construction has been done.

Asked By Aaron H | Jan 31 16
32 Answers

Roxul board used in basement as insulation against concrete wall?

I just watched a mike Holmes episode. He was building out a basement for bar, home theater, gym, etc. against all the walls he used roxul board as an insulation barrier then the walls were framed. I've read where Martin Holliday advised against this practice. Who's right? It makes more sense to use foam or foam board as it won't hold water. Thanks for any clarification on this topic.

Asked By tim gabriel | Mar 5 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
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