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5 Answers

Insulation in old home repair

Hello, I own a 1931 home. I had a window leak it damaged the plaster on an interior wall, roughly a 2'x5' section. Behind the plaster and lath was a later of loose insulation and behind that bound newspaper. Much of the newspaper was rotted, as was a section of the wood behind it. The wood backed the exterior stucco. I removed the newspaper and wood. I am unable to replace the wood that backed the stucco.Instead and added 1" rigid foam.

Here's my question: What do I use next to insulate before I put on the sheetrock, faced or unfaced fiberglass...or something else? I live in Minneapolis.

Asked By Tom Ives | Oct 21 14
3 Answers

Calculating how much air needed to even out temps for minisplit

I'm building an 800sf 2 story house, R20 under slab, R40 walls, R60 roof, as airtight as possible, but likely just double pane windows (due to cost). 12% glazing, mostly on south side, w/ 4" slab on first floor. Using Marc Rosenbaum's heat loss spreadsheet, I get around 4000BTHU building load here in Portland Oregon at the 97% coldest day of 23F and a design temp of 70F, so a delta T of 47F.

Asked By Tom Frisch | Oct 23 14
7 Answers

Attic insulation — existing

I have a 1800 sq. ft. ranch home built in 1969. Climate zone 5. Existing attic floor/ceiling area has a layer of 3" fiberglass insulation with vapor retarder facing the heated space. The second layer of insulation is a 3" layer of fiberglass with vapor retarder facing the attic area.

Both layers have been installed inside the joist bays and stuffed very tightly at the top of wall/ceiling intersection-no soffit vents in place. The roof has box vents and gable vents in place for ventilation.

Asked By bob prince | Oct 22 14
6 Answers

What kind of insulation would you recommend for a 20' shipping container being renovated into a home/studio space?

I'm renovating a 20' shipping container into a home/studio space and am wondering what would be the best "green" insulation to use. I will be doing some interior framing so would like to insulate the inside walls and floor. As well, I am building a green roof/deck that is framed using the structural strength of the container (no weight on the center of the roof) and would like to add insulation between the joist supports and deck floor (approx 3" - 9" above the container roof) and the steel roof.

Asked By Sarah Beckstrom | Jan 19 14
2 Answers

Large structure with sealed attic / fiberglass

I have a 48x75 post frame structure with a metal ceiling. Prior to putting up the metal ceiling I installed a 6mil plastic vapor barrier. The entire interior is encapsulated with the 6mil plastic under corrugated barn/ag panel metal. I want to blow R60 into the ceiling, but my metal spans 8.5'. I am worried about the weight of cellulose. I used R-panel on the ceiling for a higher load rating and span, but I still think R60 with fiberglass would be much lighter.

Asked By W Ahrens | Oct 22 14
11 Answers

Window U-value comparison to wall R-value and window replacement

We have an 1870s Victorian farmhouse that doesn't have insulation in the walls, and to keep it simple, we cannot add insulation in the walls without going to great expense, more than we can afford.

Asked By Keith Miller | Oct 20 14
6 Answers

Minisplit - One indoor unit for two adjacent rooms?

Do any of the minisplit manufacturers offer a wall mounted indoor unit that will service two adjacent rooms? I'm considering a minisplit to replace the gas furnace and a/c in my 1300 sq. ft. single level home in zone 3A (mixed-humid). Without a shared indoor unit on the common wall between two bedrooms, I might need five indoor units. The multizone minisplits seem to jump from 4 to 8 zones and the price jumps too. I understand the technical problems with one wall unit serving two rooms, but have any of the manufacturers solved them.

Asked By Steve Robertson | Oct 23 14
4 Answers

Spray foam over XPS on external wall

I purchased about 600 bdf of spray foam, and had planned on using it for my rim joists of my baasement (about 200 board foot of it). My house is a walk-out, so I have a combination of poured concrete walls and above-grade 2x6 stud-framed wall in the basement level.

I have sheets of 1" XPS available, so I was thinking about layering the XPS rigid foam sheets on my 2x6 walls, at 2" thick (possibly 3") and then covering that with a 1" layer of spray foam to air-seal it.

Asked By Jeff M | Oct 22 14
3 Answers

Add R-14 Roxul between the garage attic and the house?

I am currently in the process of insulating my attached garage using Roxul R14 "ComfortBatts". I live in Winnipeg and from experience -- when I did this in my last house -- it can improve the temperature by 10-15 degrees Celsius in the winter, without any heating. (And that was with a non-insulated garage door; my new house has insulated garage doors!)

Asked By Mike Lucas | Oct 23 14
1 Answer

“Radon Mitigation Systems” article

“Radon Mitigation Systems,” June / July 2014, pg 86 -87: Holes on pipe.

I look back at the article from June / July 2014, “Radon Mitigation Systems,” page 86 -87, and notice the drawing with the holes on the pipe point up instead of pointing down?

I was wondering, is this so people that read the article would see what was meant by the perforated pipe?

Asked By karl neemann | Oct 23 14
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