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8 Answers

I am preparing my attic for some additional insulation and was wondering what the consensus is on this subject. I currently have a fair amount of plywood flooring in my attic, installed over R19 fiberglass batts that were laid in between 2X6 ceiling joists. The batts are faced, installed with the paper side down (towards the ceiling sheetrock). I was planning to blow cellulose over these floored areas, leaving the plywood in place, but I thought I better be sure there wouldn't be issues with moisture, etc. Does the plywood need to come up or can I go over it with the celullose?

In General questions | Asked By Tommy Detamore | Aug 19 14
7 Answers

All this talk about ductless minisplits is making me dizzy. If a forced air furnace gives a bad atmosphere in a building, doesn't a minisplit per room just give many bad atmospheres?

Dana reminded me on another post that a forced air furnace increases infiltration/exfiltration. Well, why doesn't a minisplit heater or cooler do the same?

In General questions | Asked By flitch plate | Aug 19 14
4 Answers

Hi all,

I would like folks to offer any advice/criticism on the following wall and roof assemblies from a moisture control standpoint as well as any other concerns they might have. In addition I have a few specific questions on HVAC options. I know that many of my concerns have been addressed in various Q&A's but it is the specific circumstances that I am concerned about here.

In Energy efficiency and durability | Asked By Lowell Garner | Aug 20 14
37 Answers

I had R60 blown into my 1000sqft attic where there was previously only about R11. Baffles were installed in almost every roof rafter. Air sealing of attic floor was performed. This is a low pitch asphalt shingled hip roof over the whole house.

In General questions | Asked By Jeff Watson | Jul 12 14
6 Answers

Is the technique easy to learn? How many shims crews would you use on a window?

In General questions | Asked By David A Flannery | Aug 18 14
13 Answers

New construction, zone 4 on the line of zone 5 (47460).

Bonus room over garage with radiant floor heat in concrete floor.

My floor system has some areas that are blocked off with framing to add support to the ends of the floor in the bonus room. What can I do to insulate those blocked off areas before the ceiling goes in? Would 3.5" of open-cell be enough tot help with keeping the bonus room warm or would it completely block any benefit of migrating warm air from the below garage floor?

In Energy efficiency and durability | Asked By Anthony Hughes | Aug 18 14
3 Answers

Having IAQ problems with a 5 year old home on the coast in South Carolina. We had the attic foamed with Demilec Open Cell Foam and crawl space done with closed cell a few months after we moved in. Blower door tests performed after the foaming (forgot the #) revealed the home is very tight, and in summer months we are experiencing the "Fishy" odor when the sun beats on the house and the AC is running on the second floor, first floor not too bad, also not too bad during the winter.

In General questions | Asked By Tom Oelschlager | Aug 19 14
12 Answers

New construction zone 4 on the line with zone 5 (47460)

Bonus room over garage with radiant floor heat in garage floor

2x12 bottom cord in the floor and 2x8 rafters.

I plan to pre-hang drywall on the knee wall in the bonus room and spray 3.5 inches of open cell foam in between those studs. Then I plan to install 1.5 inch fiberglass faced PolyIso rigid foam on the attic side of the knee wall and tape the seams.

In Energy efficiency and durability | Asked By Anthony Hughes | Aug 18 14
12 Answers

I will be having my attic sealed and insulated with closed-cell spray foam. However, the design of my house makes this a bit more complicated because my roof cuts into the second-story ceilings at the front and rear edges of the house (will make more sense if you look at the attached pic).

Above this part of the ceiling, there is only some very old batt insulation (less than R-8) and the roof deck. The house doesn't have eaves/soffits, so there is no venting in this area.

In Energy efficiency and durability | Asked By Matt Culik | Aug 14 14
5 Answers

For a large scissor truss (top chord 31" above bottom chord), we want around R-70 but no more. How do you 'contain' the blown in, or how would you use batts?

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In GBA Pro help | Asked By David A Flannery | Aug 18 14
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