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I’m building a brick bungalow in the northern edge of climate zone 5, and I’m trying to decide on insulation for my main floor. My drawing calls for 1” (R6.5) rigid insulation (polyiso) mounted directly on the 2x6 exterior main floor studs, then batts and poly in the bays. Instead of the batts and poly, I would like to do cc spray foam with no interior VB and just drywall with latex paint. Is it okay to spray the inside face of the polyiso? I’m concerned about the heat created when spraying, the vapour permeability for inside drying, and the possible double VB.

Asked By Jeff Conners | Aug 15 14
6 Answers

Hi there,

Just want to be sure I'm not missing anything ---from the reading I've done, it seems that most PVA woodworking glues are fairly nontoxic...We have specified no or low-VOC products for our remodel, but our contractor is not an expert in this area. They want to use Titebond II. It seems like a safe choice. Does anyone agree or have a better suggestion for a carpenter's (wood) glue -- aiming to have a minimal impact on indoor air quality--very limited off gassing.

Asked By Mindy Munger | Aug 14 14
2 Answers

Finally am at the point of redoing my attached Ell roof on my 200+ year old colonial.
This is what I currently have.
Zone 5

Inside 3/4 inch pine (obviously very air leaky) cathedral ceiling, Behind that it appears to be a foil faced fiberglass. Prior owner did this some time in the 80's. The sheathing is 1 x 10 running from peak to soffit ( again very leaky). There are 2 layers of asphalt shingles, then a 1 inch layer of Styrofoam insulation board with another layer of asphalt on top of that. Fun Fun!

Asked By terry grube | Aug 14 14
3 Answers

My roof (zone 3B) needs insulation, but between Martin's concerns and the inexperience of the contractors in this market, I am conceding that 5" of polyiso foam isn't going to happen. I think that 3.0" nail base (R15) can though (with taped seams). I'd like to get closer to the code minimum of R30 for the assembly. I would rather not tear out the finished interior vaulted ceiling (cedar shingles on battens on felt paper, I know, strange), but the lousy interior air barrier (i.e. the felt paper) concerns me.

Asked By Keith Richtman | Aug 14 14
4 Answers

I have a 1000 sq ft single story house in the SF Bay Area, and I'm paying hundreds of dollars a month to run the central AC and a window unit. And even then on hot days it sometimes gets up to 80ºF inside. Ducts run through the uninsulated "vented" attic (only vents are two holes at the gables).

Asked By jim brooks | Aug 12 14
17 Answers

Recently our contractor indicated he was complete with the insulation installed with cellulose in the existing walls at our home and wanted a signoff for customer satisfaction. Our home has cedar shingles, tar paper and pine tongue and groove sheathing. He removed the outer shingle and drilled through the tar paper and pine sheathing to install cellulose. THen he installed a styrofoam plug and put shingles back over. However, my husband was concerned that the area that was drilled and then filled with styrofoam may have moisture or leakage.

Asked By Katie Nunez | Aug 10 14

We are designing a house in a 5A climate zone and am wondering if anyone has any experience using a desiccant wheel system for residential cooling?

Asked By Nathan Kipnis | Aug 14 14
2 Answers

I'm about to break ground on a 1.5 story, 2100 sf Cape Cod house on Cape Cod (lots of knee-walls). The first floor is to be heated with Wirsbo Joist Trak. Also, the large room over the garage will have an insulated floor to allow for future conditioned space(mini-split). The house will use 11 7/8 I-Joists exclusively due to the open concept design and all floor surfaces above I-Joists will be glue and screw 3/4 plywood. My building code requires I use/meet the energy star checklist.

Asked By A Guy | Aug 13 14
42 Answers

Hi all,
Can editors step out from behind the curtain to ask opinions, too? I'm planning to redo my garage shop this Fall and although my primary heat for the space is a woodstove, I'd love to have some supplemental heating, and cooling in the summer would be great, too. I'm no schlep when it comes to remodeling work, but have never installed or seen a mini split install. Would I be a fool to try the install myself or have the kits gotten streamlined to the point that its basically plug and play, complete with factory-charged units and quick connect line sets, etc?

Asked By Justin Fink | Aug 22 13
6 Answers

Is there a safe way to tile a shower floor with a drain if I don't use the plastic tray like most showers have?
I heard someone mention there is a plastic tray that you can tile over?
I know the tray has less leakage and mildew mold but the tiles look so much nicer and richer.

Asked By maria teri | Sep 8 10
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