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0 Answers

Airtight electrical boxes in masonry house?

Do I need to use airtight electrical boxes on a masonry/concrete house?

Cement plaster will be my interior airtight layer, but people are telling me that wall itself is airtight enough not to warrant the search for airtight electrical boxes.

In General questions | Asked By davor radman | Apr 27 17
9 Answers

Building a new home in Climate Zone 5 — Need insulation help

We are building a new home in zone 5 (Michigan) and I would like your recommendations on how you would insulate the walls and roof/attic space.

The home is 3500 sqft with 2750 on the main floor and 750 upstairs. The main living space (kitchen, dinning, living room) is open concept with a cathedral ceiling. Other areas have a more traditional attic space.

The basement will be unfinished and we will use 2" rigid foam under the slab and on the walls. (unless you tell me differently)

Walls are 2x6 construction.

In GBA Pro help | Asked By NKoenig | Mar 26 17
0 Answers

Exterior wall installed on perimeter of osb floor yet rest of room is a cement slab?

Hi all.
We recently purchased a house and upon ripping the carpet out in one of the bedrooms noticed that the exterior wall has been built on top of an osb type floor, however directly adjacent is the cement slab. I've attached a picture.

I'm hoping that someone here may provide some insight into why the slab/osb combo has been used. The cement slab has heating put in the cement.

The house was built in 1998. It's considered a 'walkout'.
We are Alberta Canada. Thanks.

In General questions | Asked By frugalmumma | Apr 26 17
6 Answers

1974 construction retrofit

A friend is looking to replace siding and windows on his 1974 house in climate 4 marine. The main floor and upstairs walls are 2x4 and the basement walls are 2x6. There is timber framing inside that I suspect bridges to the ext sheathing w/o any insulation. Where he has removed some of the vinyl siding, he found fiberboard sheathing (R1.32 stamped on it). I don't know what is under that. (The garage is just studs + fiberboard + siding). The gable walls have 3" overhangs and the roofing is 2 years old.

In Energy efficiency and durability | Asked By Mark Walker | Apr 25 17
5 Answers

Manufactured foundation drains, e.g. Z-Drain

Our builder wants to install the foundation drain on top of the footer instead of alongside of it. We complained that this would potentially give us a line of standing water above the footer/foundation wall joint (though it would remain some inches below the basement slab level. ) We will have Tremco Tuff n Dri waterproofing all along the wall and along that joint, so if it does a perfect job indefinitely then we should be fine. But if not, we could get some wicking up that wall.

In Green building techniques | Asked By William Costello | Apr 26 17
5 Answers

Cape Cod attic — cellulose machine

My finished attic in my cape cod has terrible temperature regulation up here in central Maine. So far I've put 1 inch foam between the floor joists sealed the gap with foam. I've also spent days air ceiling the upper attic. Next step is for me to dense pack the sloped ceiling, which is made up of 2x8 rafters. I'll be using accuvent cathedral ceiling extensions to provide ventilation. The sloped ceiling is about 5.5 feet long so I'll be connecting two of the vents together and stapling at either side. The house is about 34 feet long and I have slopes on either side.

In Green products and materials | Asked By SciFiJock | Apr 25 17
2 Answers

Moisture control / insulation for new cinder block shop with loft / den.

Hello Folks

I've been reading through the forums for an answer to this question, but haven't been successful in finding one. I'm building for the first time, so this is a learning curve for me.

I live in west Florida, and have a project in the works. I'm going to be building a 55ft x 38ft workshop, that will be 2/3 work space, and the remaining 1/3 will be a loft / den living space with a small kitchen, laundry area, and bathroom. So around 1400sq ft. I am planning on controlling climate with a 3 air handler mini split system.

In General questions | Asked By brew0688 | Apr 24 17
1 Answer

Linseed oil paint--your experience wanted!

Through the years there have been a couple mentions of the stuff (Allback, Viking--old school linseed based paints) on the Q+A section here, but to date I haven't seen any candid reviews or recaps of folks' experience.

In Green products and materials | Asked By jonathan nagar | Apr 26 17
4 Answers

Tar Paper vs Red Rosin Paper

I'm having hard wood floors fixed and the contractor wants to use Tar Paper vs. Red Rosin Paper. Is one more health-safe than the other?

I'm very sensitive to smells and chemicals. We had Fiberlock put down on the subfloor that I was sensitive to. The contractor said the Tar Paper would serve as more of a vapor barrier to it, but i don't want to add more chemicals if Tar Paper is less safe than Red Rosin. Thanks!

In Green products and materials | Asked By Masb H | Apr 26 17
7 Answers

Deep blown in cellulose for attic - questions

I have a few questions regarding deep (beyond R60) blown in cellulose for an attic. Cellulose is relatively cheap and I'd like to maximise my attic insulation without causing any other issues:

1. Several manufacturers of cellulose insulation have depth/R-value charts that stop at R60. Is there any practical reason for this, or is it just because most people don't bother going above R60?

2. Does compression above a certain depth negatively affect the performance of the insulation in any way? I.E. does your R-value/$ go down appreciably beyond a certain depth?

In Energy efficiency and durability | Asked By Lance Peters | Apr 24 17
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