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11 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
15 Answers

I am ready to insulate a new home, and need to make a final decision. I need help.
I have been the recipient of many helpful tips and guidance from thes pages as well as other green forums and it's all kind of coming to a head in our new home build as I attempt to make a decision about the insulation we will use. Here is the specs on my houses wall stack up

LOCATION: 47460 On the line of upper climate zone 4 and lower 5

2x6 exterior walls, 1/2 inch sheathing with tyvek, 1.5" polyiso foam with taped seams, vinyl siding

In Energy efficiency and durability | Asked By Anthony Hughes | Aug 8 14
4 Answers

Not including the cost of the blower door test itself, I am looking for a ROM materials and labor cost per ft-2 to seal up a conventional 2 x 4 framed house, sheathed, sided, windows, doors, stud bays, lid, etc.....?

If someone that has done it can estimate labor hours to get to 5-7 ACH-@ 50 I can factor my local labor rate. Please include the trail and errors, IR and smoke back and forth, etc. Or if you sealed up some ft-2 home let me know how long it took...

Thanks!

In PassivHaus | Asked By Terry Lee | Aug 20 14
2 Answers

I got some basic ideas from Martin's fine article here: http://www.finehomebuilding.com/design/departments/energy-smart-details/...

In General questions | Asked By Tommy Detamore | Aug 21 14
3 Answers

I am in the process of shopping for window flashing tape and am running in circles about what brand (and type) of flashing tape to purchase. Obviously, price is a consideration, but I do not want to sacrifice quality and longevity.

In GBA Pro help | Asked By Matthew Michaud | Aug 20 14
16 Answers

I'm building a new house, and would love to hear feedback on the insulation plan. It can be found here: http://lazukars.bitbucket.org/house.png

DESIGN GOALS:

- Have a consistent insulation pattern up from the basement and up through the roof. In this case XPS on the exterior and ccSPF on the interior.
- Eliminate thermal bridges wherever possible.
- Double the insulation required by code

CONCERNS WITH THIS DESIGN:

- Foam Sandwich: The current sandwich of XPS on OSB on ccSPF will create OSB rot. The OSB will not be able to dry to the interior.

In Plans Review | Asked By Ryan Lazuka | Aug 18 14
7 Answers

From all the reading I have done, am I correct that I don't want to use closed-cell and need to use open-cell spray foam in the band areas of floor joists of the basement to 1st and 1st to 2nd floor areas when I have used polyiso sheathing on the outside of the walls?

I believe that is correct because of the perm is so low for the polyiso and you don't want to use another very low-perm product like closed-cell spray foam sandwiching the Zip wall sheathing. I'm just confirming if I read everything correctly.

In Energy efficiency and durability | Asked By john bell | Sep 19 12
1 Answer

I have an attic above my kitchen with 3 interior walls and I am trying to figure out how to insulate it correctly.

Currently the walls facing the bedroom and the entry way have fiberglass insulation.
The floor has cellulose insulation. ~2-3 inches.
The ceiling rafters has ~4" of white fiberglass/denim insulation inside of perforated plastic bags between the ceiling rafters, this appears to be pretty consistent, but I suspect it is leaking a bunch of air.

The roof line is several inches about the existing insulation and connects to the space above living rooms vaulted ceiling.

In General questions | Asked By John Reuter | Aug 20 14
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
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
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