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0 Answers

BuildingGreen publishes special news stories for April 1st

Here's a link to one of BuildingGreen's special news reports for April 1st:
Judge Robs Yost of Gold Medal in WUFI Modeling.


In General questions | Asked By Martin Holladay | Apr 1 15
3 Answers

Foam under slab details

New residential construction, Zone 4A, slab on grade with attached garage. Three questions:

1. Most builders around here pour the entire slab flat; in other words, no slope to garage door and no step up into the house. Is this an okay practice?

2. I plan to put 2 ½" of foam sheets below the slab for R-10. Is there any compelling reason to continue the foam under the garage part of the slab (there would be no thermal break, the slab would be contiguous).

3. What is the detail for continuing the foam below bearing walls that will be supported by a thickened slab?

In GBA Pro help | Asked By David McNeely | Mar 31 15
1 Answer

More wet fiberglass

Some of y'all might remember this picture...
and the discussion that went around it, concerning careful backoff
[from the wall] and sealing-up of the outer duct sheath to make sure
no water infiltrated into the fiberglass between. This was for the
intake duct on my HRV setup, the coldest part, and after retrofitting
same on my HRV setup accordingly it was fine all this winter.

So I was downstairs putting the snow shovels away [wishful thinking?]
and happened to bump the end of the *exhaust* side duct, which

In Mechanicals | Asked By Hobbit _ | Mar 31 15
0 Answers

Reasons NOT to use Fibertec Windows for your Home

When I started window vendor selection for my new home build, I was concerned about the customer service and issues meeting delivery deadlines I had read about. I was reassured by the Sales Director that these were "issues of the past" given changes that had been made in the company recently. As I would learn, this is the furthest from the truth.

In Energy efficiency and durability | Asked By Darin Anderson | Mar 31 15
14 Answers

Alternate cathedral ceiling retrofit

I have a project related to a thread titled "How can I best retrofit and insulate an existing cathedral ceiling?" In my case, the zone 4b semi-arid west texas 1978 home's cathedral area has low density glass batts (or none) along with 1x10 or 12 deck boards over 2x12 rafters. The shingles above this unvented space have some blistering, and I was going to replace them along with resetting two skylight curbs that are incorrectly installed and caused some sheet rock damage from skylight leakage.

In GBA Pro help | Asked By Glen Poklikuha | Mar 27 15
7 Answers

Insulating truss joists 16" on center — Best way?

Batt insulation for 24" o.c. The 2x lumber is 23" wide. The truss joists I'm looking at are 2x4 lumber 24" o.c. The space between the trusses is 21.5". Does anyone know if R-19 batts are available in 21.5 or 22"? Seems like squeezing a 23" wide batt will not work well.

Also the tiger wires used on 2x lumber will not work well on a truss. Is there another method of holding the batts up to the floor?

In Energy efficiency and durability | Asked By Walter Gayeski | Mar 25 15
23 Answers

Insulating wood I-joists with Roxul

O.K., to repeat, I'm building a 1-story house in Zone 4C. Builder is using wood I-joists 16" O.C. for the floor. After considerable thought and reading, including comments by Dana Dorsett and research by Washington State University, I decided that an open crawl space would work for me. However, I have insisted that we use good insulation: R-24 (commercial size) stone wool batts by Roxul for the floor insulation. This comes in 16.25" widths. My builder says, Fine, but how are we going to shove them past the flanges at the top of the I-joist so that they're snug against the floor?

In Energy efficiency and durability | Asked By Gordon Taylor | Nov 21 13
8 Answers

Converting old outbuilding to heated workshop

I have a wooden garage, built in 1929 in coastal Maine, in remarkably good shape. It's got a post and pier foundation and had the front ripped off to convert to a 2 car garage in the 90's. I plan to reconvert it to it's original intent as a workspace. Like most of these old outbuildings in our neighborhood, the lawn has grown up to the base of the siding (or maybe they were intended that way) and there is a major negative grade inside, kind of like an earthen crawlspace foundation. When I started digging around and found this out, I got very worried about rot.

In Energy efficiency and durability | Asked By A. Bradford | Mar 20 15
2 Answers

Should I air seal and insulate above the ceiling of my attached garage?

My house has an attached garage. The attic spaces above the house and the garage are not separated; there is no wall between them in the attic--it's all just one big attic. I am currently having the part of the attic over the conditioned space air-sealed and insulated. Should I additionally air-seal and insulate the ceiling above the attached garage? Even though it's not conditioned space? There is a water heater in there FWIW, and the garage does get cold in winter and hot in summer.

In Energy efficiency and durability | Asked By Nathaniel G | Mar 30 15
1 Answer

Two questions: Rigid foam in attic space

1. I have some knob and tube wiring running about 3 inches above the 1st floor ceiling, behind a kneewall. After having an electrician look at it I'm going to box it in with plywood, leaving a good size air gap. This will decrease the R value for this area. Is it ok to put 1 inch rigid foam on top of the plywood? This would make from bottom up: 1st floor ceiling, wiring with air gap, 1/2 plywood, rigid foam, cellulose, open attic and then roof.

In Energy efficiency and durability | Asked By Jeremy M | Mar 30 15
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