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7 Answers

Insulating conventional corner

I’m converting our 2car attached garage into conditioned shop. I’ve began weather sealing and am trying to decide what to do with the conventional corners box corners. Not sure what the proper term is for that but I’m referring to how the last and first stud in a corner of two perpendicular walls meet so that they essentially form a post, or a situation where there is an empty cavity facing the exterior and now way to access it from the interior.

I’m thinking I should:
-cut out one stud out and toenail it back to the sheathing so it’s oriented like a “California corner”?

In GBA Pro help | Asked By kevek101 | Jul 19 18
16 Answers

N.Y. Times article on dealing with heat wave

I read this article


And while most of it is silliness it did get me wondering if white or reflective window coverings would make an appreciable difference. Assuming high SHGC windows of course (not sure if my windows are or not).

Your thoughts?

In Energy efficiency and durability | Asked By Alan B | Jul 16 18
7 Answers

Hybrid insulation: rockwool + foam board (and canned foam for airtightness and extra R-value)

This my first home, very hand have done remodels and stuff before. I wanted to use spray foam but it is out of the question cost wise. I have a 1900 house with plaster. I will be going room by room removing plaster to wire, insulate, drywall and replace windows. I have not found a lot of info on making a home air tight yet. So here is 2 plans not sure how they work work out:

Note 1 The plaster wall should give me 4-4.5 inch of stud bay depth.

Note 2 will be pulling down vinyl siding to put up 1 inch r5 foam board outside, then hopefully reusing siding.

Plan 1:

In Energy efficiency and durability | Asked By NewHomeOwner95 | Jul 20 18
12 Answers

Is it necessary to insulate the ground in a Zone 5B crawlspace?

Small, 192 sf building with a ventilated crawl space, zone 5b, Central Oregon, ground freezes in the winter. My plan is to seal vents and convert it to a conditioned space using rigid foam - R15 on walls, R20 at the rim joist. No cavity insulation between floor joists. Building has 24" stemwalls and a 6" tall footing. The footing and stemwall were poured flush with each other on the interior, and the dirt floor inside is level with the bottom of the footing.

In Energy efficiency and durability | Asked By KevinEJ | Jul 19 18
0 Answers

Ventilation Baffles over Lean-to?

My father is building a detached garage, and we are planning to put insulation in the ceiling within the next couple weeks. I know that we will need ventilation baffles on one side where the roof meets the walls. But on the other side, the roof has a lower slope and forms a lean-to. When I talked with the builder today, he said that we don't need to install ventilation baffles on that side, as there is adequate space between where the top of the insulation will be and the rafters. Can I trust his judgment?


In Energy efficiency and durability | Asked By Dylan Hillman | Jul 20 18
19 Answers

Triple glazing or high-end double glazing?

I have decided on Milgard fiberglass windows for our house. I like the price point and warranty but I'm trying to buy their best window. The rep has tried to talk me out of the triple glaze but I think it's because he is not familiar with them in this area. He says the high end double pane with their best coatings have better u values and they can't or don't put that coating on triple pane. The cost is about the same. Triple seems to be better to me but I could use some advise. The house is in Missouri. Thanks!

In Energy efficiency and durability | Asked By User-7088022 | Jun 12 18
26 Answers

Help with air-source heat pump sizing

We are looking into getting minsplits to take care of most of our heating and provide some cooling. We currently have no AC and have a steam boiler which also heats our water. We live in Concord, MA, west of Boston. My concern is about correct sizing of the units. Our house is 1462 square feet not including the basement. Main floor is about 800 square feet so upstairs is about 600. Upstairs is a finished attic with probably average insulation. Walls are 2x4 construction and are insulated. House was built in 1950. We have 2 pane low e windows.

In General questions | Asked By Lyell Slade | Jul 4 18
6 Answers

Tape widths

I'm doing some air sealing on plywood seams using 3 m flashing tape. Is there some standard range of what the width of the tape should be. Like wall to ceiling edge seam or floor to wall edge seam or even just the seams between two sheets of plywood. How does a person determine an appropriate width to use? Thanks

In General questions | Asked By Smokey059 | Jul 18 18
16 Answers

Open truss post frame roof

I am building a cabin on Ky lake and want to do it post framed. The floor plan calls for vaulted ceiling over the kitchen and living area. I want to do exposed scissor trusses on 8’ centers. My thoughts were to span the trusses with vertical 2x6s on 24” centers and fill with batts then cover the bottom side between the trusses with tongue and groove pine. So what would I cover the top side 2x6s? I was thinking osb then 2” rigid foam then layer of 1/2 plywood screwed to the 2x6s then foil bubble wrap then metal.

In Green building techniques | Asked By kcov | Jul 8 18
9 Answers

Geothermal heat pump to preheat propane water heater water?

I have an older house that was built in the early 60s. The first floor has poured concrete foundation walls on the rear and sides of the house. One side and the back of the house is 5' into a soil... one side is about 1.5' into the soil and the front is at grade. When we bought the house it had a heat pump that ran the primary cooling and heating needs. It runs forced air through ducts in the attic and down to the first floor using ducting through some closets. This system is on its last leg.

In Mechanicals | Asked By user-6999468 | Jul 18 18
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