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3 Answers

Better Wall Design?

I have a question about a wall design I haven't seen before.
What if we took 2x6 top and bottom plates with 2 - 2x4 studs 24" on center turned 90 degrees and nailed to the top edge and bottom edge. One on the outside and one on the inside with a small brace in between to stiffen the 2x4's for nailing. Kind of like a staggered stud wall, but the studs are directly opposite each other. This should provide strength and stop thermal bridging if we flash and fill the outer wall with 2 pd closed foam and fill the inner wall with R-15 fiberglass.

In Energy efficiency and durability | Asked By grady snapp | Jan 4 14
7 Answers

Tube skylight, Solaro Day, or just an LED fixture?

We have a back hallway in the house we're building that will need to be lighted. We're definitely not getting a standard skylight. My wife wants a tubular skylight. I've been looking at a product called the "Solaro Day" PV fixture which uses a small solar panel on the roof that powers an LED ceiling fixture inside. It uses DC power, to light Osram LEDs. Here's a link: http://www.katahdincedarloghomes.com/110910solaroday

In Green products and materials | Asked By Gordon Taylor | Dec 30 13
3 Answers

Installing windows to be replaceable without compromising the WRB

I'm (very slowly) planning to retrofit a few inches of foam onto my house, with a rainscreen and new fiber cement siding. I don't think new windows are justified from an energy point of view, nor do I particularly want to spend the money on them. But they're vinyl and I really don't think they're going to last as long as the siding, so I'm going to re-install them with proper flashing with the intent of making it possible to replace them in the future without too much pain.

In Green building techniques | Asked By Nick Welch | Jan 3 14
2 Answers

Water and air control strategies for retrofit applications

I have an old house with no insulation aside from 1/2" of polyiso installed to the outside of old wood sheathing and siding and covered in vinyl. Based on previous posts and research I have decided I want to add exterior foam insulation while residing. I am trying to make a plan to get the greatest "bang for the buck" and I am encountering varying advice. Here are my observations:

In Green building techniques | Asked By Brian Coppola | Jan 3 14
3 Answers

How to insulate and vent this roof?

I would describe it as a lean-to roof against the tall side side of a shed building. We have just acquired this building and are faced with high energy costs and ice dams. [More information in Comment #1.]

In Energy efficiency and durability | Asked By walt ott | Jan 3 14
3 Answers

Air sealing did not improve blower door test results. Why?

I recently air sealed and insulated my house as follows:

1) air sealed 40 recessed cans;
2) air sealed all major attic penetrations;
3) spray foamed all my basement and crawlspace sills;
4) topped up all the attic insulation to 50R

The blower door test results were the same on post-test and pre-test. How does that happen?

Alternative retest methods did not change this outcome -- no improvement detected. The energy auditor could not explain it.

In Energy efficiency and durability | Asked By charles halaby | Jan 3 14
13 Answers

Roof for small cold-climate A-frame "writing room"

Hi Martin --

I'm helping a friend build a small, simple 10x12 A-frame in northwestern MA (Lanesboro). It will be in the woods a hundred yard from his house, and mostly be used as a "writing room" to escape the house, but occasionally as a bunk house for guests who have overstayed their welcome (like me). Single room for the bottom, half loft on top.

In Green building techniques | Asked By Nathan Kurz | Jan 1 14
4 Answers

I have a question about sizing ductless for cooling

I'm building a 1,043 sq ft, 1 and 1/2 story cottage. I had independent heating and cooling load calculations done. I'm going with two Mitsubishi Hyper heats, one up and one down.

In Mechanicals | Asked By Andre Jones | Jan 2 14
6 Answers

How to properly insulate a tongue-and-groove ceiling?

I live in climate zone 5B in northern California and I'm finishing a shop building that I plan to heat in the winter. My plan for the ceiling is to cover it with tongue and groove pine. The rafters are 2x8', 2' OC that are vented at the ridge and with soffits at the eaves. I've installed R21 Kraft faced insulation between the rafters (Kraft side facing the interior of the building).

In General questions | Asked By Richard Callas | Dec 26 13
4 Answers

Diverting a stove pipe interfering with chimney draft?

I am in the planning stages of building a home, which includes a wood stove in the great room. To create the best draft and because of window location, I am limited on where I can place my stove. The best location is centered in my great room, but places it directly under an supporting beam. My thought is to run the stove pipe several feet up from the top of my stove, divert it around the LVL with a 45 degree elbow, and another to bring it back to vertical and continue straight through to the roof.

In General questions | Asked By Matthew Michaud | Jan 2 14
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