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6 Answers

Vented SIP roof — fascia detail

Trying to find a photo or a detail of a vented SIP roof fascia area. Typically they use 1x or 2x furring strips on top of the SIP and then the layer of sheathing and roofing material. How the fascia gets finished is something that is hard to find. There is a 1" or 2" vent gap there so how does that all come together?

I did an internet search and could not locate any such detail.

Asked By Peter | Apr 16 15
2 Answers

Photos of site-built ventilation baffles

For an upcoming article on site-built ventilation baffles -- that is, baffles used to create ventilation channels under roof sheathing -- I'm appealing to GBA readers to send me photos of your work.

You can post the photos here, or send them to me by e-mail: martin [at] greenbuildingadvisor [dot] com.

I've heard of builders making these baffles out of rigid foam, cardboard, plywood, and fiberboard. If you have a favorite material, including one I haven't listed, please let me know about it.


Asked By Martin Holladay, GBA Advisor | Apr 16 15
27 Answers

Sizing minisplits for adequate heating & cooling in a cold-climate Passive House

We are building a 2300 square foot Passive House in the midcoast area of Maine and are having trouble choosing and properly sizing our mini splits for both adequate heating and cooling. We live in an area where of course it gets below zero many times during the winter. So we are limited (I think) to the brand of mini-split we can choose from.

Asked By CathrynJones | Apr 11 15
9 Answers

Window flashing for new construction

Good morning,
I am getting ready to install windows(aluminum clad) on my new construction and would appreciate help figuring out the flashing details.
The exterior walls are made of gigacrete wall panels. The panels are basically steel studs encased in 8" thick eps. The walls will get a coating of stuccomax(gigacrete'a proprietary exterior coating). There is 3" of eps on the outside of the studs so essentially the windows will be inset a little over 3".

I am attaching a few images so the wall components/window openings can be better understood.

Asked By asim majeed | Apr 6 15
5 Answers

How much of a 2 x 6 plate has to be on the stem wall?

The real question is whether to use 6 in or 8 in blocks for my stem wall. Stem wall is 24 in high, this is slab construction.

The wall is metal, membrane, 1.5 in ISO, 5/8 OSB, 6 in plate, 5/8 drywall, trim.

If I use a 6 in block and line the outside of the ISO with the outside of the block, that puts only about 3.5 in of the plate on the block. Will this work? The good part of this system is that the 3 in of styrene on the inside of the stem wall can be let untouched and thereby give me a good thermal break between the floor and the block.

Asked By Tooger Smith | Apr 16 15
5 Answers

Reasons NOT to use Fibertec Windows for your Home

Per a phone call 4/15/15 from Fibertec, they have expressed concerns that my original posting unfairly places them in a negative light. To avoid the potential option of Fibertec taking legal action for perceived damages, I am temporarily removing this post so that I can discuss Fibertec's concerns with them and substantiate my claims in greater detail for their awareness. Once completed (shortly) I will repost my thread with any potential corrections.

Asked By Darin Anderson | Mar 31 15
5 Answers

Best HVAC options for large house in zone 5a.

I have a custom house with 3930 sq/ft of conditioned space in a development in northern Idaho, (Zone 5a). The basement is planned to be Logix Platinum ICFs with R-28, the main and upper floors planned as 2x6 advanced framing walls with cellulose, 7/16" OSB, Tamlyn Drainable Housewrap, 1.5" of Terrafoam EPS, and fiber cement siding.
I'm hoping to get the owner to agree to spray foam the attic sheeting to condition it (R-38 min.)
The basement is 1830 sq/ft including a conditioned space under a large garage. The upper two floors of living space are 1050 sq/ft each.

Asked By Nethaniel Ealy | Apr 15 15
3 Answers

Various spray foam companies


Would like to know if there any significant differences between the spray foam made by various companies?
We have two vendors in our area and one uses Bayer for Open cell and Dow for Closed cell, while the other vendor uses, Premium and Johns Manville?

Help greatly appreciated


Asked By Yasir Khan | Apr 15 15
1 Answer

How should I insulate cavities underneath a subfloor?

Part of our dining room is built over a small area that consists of 2x12 joists that sit directly on concrete. The reason this small area was built this way was because it was an extension to an old foundation.
What is the best way to insulate the space between the joists (i.e., the cavities)? This area becomes quite cold because it is on the outside edge of the house. My concern is that moisture will build up under the subfloor.

Asked By Shlomo drexler | Apr 15 15
1 Answer

New Home - Wall Assembly Review

I'm building my first custom home this summer and could use GBA's collective wisdom to vet the wall assemblies.

Zone 5a
Logix Platinum ICF basement (R-28)
2x6 advanced framing, blown cellulose, 7/16" OSB, Tamlyn Drainable WRB, 1.5" Terrafoan EPS, Fiber cement or steel siding.
Conditioned attic with min. R-38 closed cell spray foam
"Innie" window placement

Will placing the drainable WRB between the sheeting and EPS cause air flow that will serve to defeat the EPS insulation?
Does this mean I should move to an "Outie" window placement?

Asked By Nethaniel Ealy | Apr 16 15
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