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7 Answers

Mold on lumber

Hello there,

I have noticed some black spots on my lumber, that seem to be from spilled pain perhaps, but looks like some mold has grown over top.

For those of you who care enough about mold, what works well cleaning it off? I was thinking of using a mold cleaner then sanding.

If I do that, how long do you think I should give it before I start sheathing and closing the walls in?

Here are a few pics

In General questions | Asked By Rocky12 | May 19 17
23 Answers

Ductless minisplit - completed Manual J


In Mechanicals | Asked By Jeremy Archer | May 1 17
4 Answers

Is there an advantage to having radiant barrier sheathing on the roof of a house which is rather cold in cool weather?

we have an old shake roof on a house that was built in 1947 in the mild climate of san jose, california. the house is generally cold and damp in cold to cool weather.

we are now replacing the roof with a shingle roof. we were told that the new roof may help with the chill as there will not be gaps between the 'rafters."

we are trying to decide whether to buy radiant barrier sheathing for the warm to hot days, which have been hotter and more numerous in the last few years. however, we do not want to make the house even colder outside of the times of heat.

In Energy efficiency and durability | Asked By ms49 | May 18 17
4 Answers

Low-slope roof insulation questions

Q1. Can existing loose fill cellulose be dense-packed later?

Q2. On a vented low slope roof with loose fill cellulose on the attic floor, will rigid foam above the decking create issues?


In Energy efficiency and durability | Asked By Anthony Yoder | May 19 17
8 Answers

What wall set-up would you go with?

New 1 storey home build, North East of Toronto,ON, Zone 6.

Currently the plan was 4" exterior EPS foil covered with 2 x 6 stud wall filled with Roxul R22 or maybe 24.
Then I saw used paper faced Polyiso in 3" thickness from roof replacements, so I'm looking into this and trying to see if I can get enough to do 2 layers on the exterior sheathing .
So questions is what wall do you think would be a better setup?

4"EPS + 2 x 6 with R22 Roxul = R40 +/- added expensive of new EPS and 2 x 6 studs

In General questions | Asked By Dave B | May 17 17
18 Answers

Window Flashing - Housewrap over ZIP

We will be installing Housewrap over our ZIP system sheathing.

The Housewrap will act as the WRB. Windows already installed and flashed with ZIP tape.

How can we best flash the windows and doors with the addition of the housewrap, since the windows are already installed?

Also, are there moisture issues associated with using two layers of WRB against each other?

In General questions | Asked By Bridget Lamberson | May 15 17
4 Answers

Cheap cedar alternative for shed clapboard cladding, in Europe?

I'm planning to build a large multifunctional shed. More like a multifunctional yard building, 7x7m. Part will be masonry (3x3m) with wood clapboard cladding, the rest I had planned as a just a storage area, with cladding on the outside, OSB on the inside, on wood construction.

I want to use wood clapboard siding (with rainscreen). Resources I find from USA websites mostly use cedar for this purpose.

What would be an acceptable local alternative here in Europe, with regards to durability and resistance to elements, but cheap?

In General questions | Asked By davor radman | May 12 17
3 Answers

Tongue-and-groove boards for a cathedral ceiling

I'm planning to build a house in central PA which will have cathedral ceilings for all of the rooflines and large dormers. Because of the dormers, I've ruled out a vented ceiling and am thinking I need to go with closed cell spray or flash and batt. For cost reasons I'm leaning towards the flash and batt option with R-21 closed cell spray and R-19 unfaced batts for cost reasons. We are also considering doing T&G wood in some of the areas...so my question is do I need to put drywall under the T&G wood?

In Energy efficiency and durability | Asked By PAJon | May 18 17
13 Answers

Zone 4 Build--Bottom to Top

Hello all

I am building a new home in the mountains of western NC, Zone 4. Four seasons there, lots of rain. We will be building on a 31% grade with one main level and one lower level(for some reason they hate to call them basements there!). If you don't mind, I would like to start at the bottom with my proposed build and work my way up. I wanted to get this all figured out before I go to the architect and builder.

In Green building techniques | Asked By Kevin Spellman | May 15 17
1 Answer

Air transfer through soffits

Hi Martin....I am building in zone 5 and have chosen to spray the roof deck with closed foam backed with open cel. There will be no air coming in through the soffits since the foam fills the roof joist cavity above the plate on the outside walls. My question is regarding the roof joist tails beyond the exterior walls. My intention was to close those soffits with cedar without any venting considering there will be no way for air to get out if I allowed it to get in. Is this an acceptable practice?

In General questions | Asked By Consor Development ternes | May 18 17
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