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26 Answers

Mold/ventilation problems in an old passive solar house

I just tried to post a long comment on the vapor retarder/barrier article and was blocked for spam so I'm trying again here. I'm under contract for purchasing a 1979 passive solar house in Southern Maine (near Sebago Lake, but at higher elevation). The house needs a lot of work, which we were expecting, but on top of all that they unfortunately found moderate to high mold growth on the roof sheathing and rafters, along with improper insulation/ventilation practices.

Asked By Movintomaine | Apr 9 17
7 Answers

Too late for outie windows?

I framed and wrapped my house planning on innie windows. Walls will be standard construction with 6” exterior foam. Actually…I installed all the windows that way as well. With that behind me, I am feeling like the structural and performance benefits I based this choice on are overblown, and I’d like to change to outie windows. My rough openings are sized for the windows – not the windows plus extensions. I am trying to determine a way to build rough opening extensions that attach outside the sheathing.

Asked By Jim Tyler | Apr 10 17
20 Answers

Mold on the north side of the sheating in my attic

First let me apologize for the longwinded question. I purchased a house a while back it was an as-is purchase. We knew a fire had occurred several years back and seen what was presumed to be smoke damage in the attic.

The house had been re-wired, new sheetrock throughout kitchen etc. When we purchased the house the return air (duct work in crawl space) was not hooked up and this was one of the first things corrected.

Asked By Dysd | Apr 7 17
4 Answers

Spongy flat roof

We recently bought a house, in Alaska, that a commercial concrete contractor and his contractor friends built in stages as he, the cement contractor, lived in during the various stage of completion.

Asked By Timothy Robinson | Apr 9 17
1 Answer

Venting Soffit / Overhang

I'm presently building a house with a flat TJI roof. Over the living space there is sloped foam that provides the R-value for the roof as well as the slope. Above the overhang is simply 5/8" T&G followed by torch on. Above the exterior wall separating the overhang space from the "attic" space is blocking sealed with DOW XPS and spray foam. The underside of the overhang will be stained T&G Pine.

My question is, does the overhang cavity need to be / should it be (or not be) vented?

Thank you for your help!


Asked By Brandon Kennedy | Apr 5 17
2 Answers

Picture Window self-filled with Argon

Related GBA questions for this project:

Going to be addressing the exterior this season. I have some ideas on what to do with the 2 picture windows that will be kept. All other windows will be replaced.

There are 2 picture windows on the 1st floor. The glass areas are:
In dining room facing east, 5’ H x 7’ 8” W
In living room, facing south (shaded by a floor above), 5’H x 6’ 4” W

Asked By TIM LANGE | Apr 5 17
3 Answers

Update to “Attic insulation quandary”

This is an update to the “Attic insulation quandary” question posted last year. See the following links for a description of the project:

We completed the SPF insulation of the ceiling and have drywall over the SPF. Didn’t get to the new windows step before the snow came. Boarded up the openings, tarped and insulated for the winter.

Asked By Tim Lange | Apr 2 17
4 Answers

CMU garden wall not waterproofed, without drainage... now what?

East TN: Climate Zone 4A, annual rainfall about 50".

CMU block retaining wall was built without drainage or waterproofing (beginning to look like the builder skimped on the footing also—but that's a different issue). Wall was coated with Thoroseal it seems, and has been painted twice. Paint is failing, and there is mold and even moss on the face of the wall.

What to do? I added a curtain wall drainage in front of it to protect the crawlspace, but we are still looking at a messy wall through our living room sliders. What materials and method can I use to provide a new face on the wall?

Asked By David McNeely | Apr 2 17
20 Answers

Low-slope "warm" roof build-up clarification

We are advancing on the planning stages of a new build project in climate 4C (near Vancouver, Canada). Thanks to the many articles and Q&As on this site I've got myself comfortable with most outstanding issues we are facing in developing our roof and wall build ups. This is a small building used as a holiday home, not fully occupied in Winter.
With that in mind any feedback from your good selves would be appreciated.
The roof is a mono pitch (shed style) front to back at just 1:12 with no "rafter" space to hold insulation
Build up:
- Exposed 3X8 Douglas fir beams

Asked By Quinn Sievewright | Mar 26 17
3 Answers

How does ambient temperature affect wetting/drying cycles?

Hello GBA pros & community! I've been a lurker around here for awhile, but this is my first post. I'm enclosing a timber-frame in southeastern Manitoba (climate zone 7A), and plan to build a vented roof assembly with dense-packed cellulose insulation. For reference, the specific assembly I have in mind is as follows, from the inside:

-timber rafters
-1x6 T&G pine ceiling
-ice & water shield (interior air-barrier, class I vapour retarder, and temporary rain protection for the timber-frame)
-18" deep non-structural 'trusses' dense-packed with cellulose

Asked By Benjamin Pries | Mar 22 17
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