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3 Answers

"Flash and batt" question: can I re-use existing batts?

We had a tree fall on our house and damage a section of roof that includes a cathedral ceiling/roof. It was previously insulated with R30 batts (faced) under the rafters followed by drywall (this is in part of our bedroom). We are planning to spray 3" of closed cell foam under the rafters and fill the remaining 6.5" with fiberglass batts. I realize that the R30 batts are designed to fill an 8-9" rafter depth but was wondering if re-using them would significantly compromise their insulation properties vs using new R-19 batts.

In GBA Pro help | Asked By Rob Moore | Aug 17 16
19 Answers

How should I address the lack of plywood boxes for my double stud wall rough openings?

Blame it on lack of clarity on my part, but when my framer built my double stud walls he didn't oversize the window rough openings to account for 1/2" plywood sheathing connecting the inner to the outer walls. He figured that this gap could be covered solely with drywall.

What is the disadvantage of not having plywood in this location?

In Green building techniques | Asked By Adam Peterson | Aug 12 16
5 Answers

Provia Entry Doors

Found the Provia entry doors online. They claim a U-Value of 0.10 on the fiberglass polyurethane core doors.

Anyone use these doors?

What about cost for a 36" x 84" door?

In Green products and materials | Asked By Peter L | Aug 12 16
10 Answers

Fiber-faced rigid foam as basement insulation?

I have some extra fiber faced rigid foam sheets that I have left over from our build. Would this be OK to use as wall/floor insulation for a small crawlspace? The fiberglass facing has me wondering if it will be a problem.

In Green building techniques | Asked By Clay Whitenack | Aug 11 16
6 Answers

High humidity in new construction - Mitsubishi Multi System playing a role?

Hi Everyone - Longtime lurker and looking forward to being a member of GBA. Thank you in advance for advice.

Question/concern I have is high humidity in new home I've built for my family. Highest levels in upper level bedrooms. Project location is Western Maryland (Zone 5A I believe). Here are a few details about construction that might help:

Main Level - 1,223 sq.ft. - ( Dense packed cellulose)
Upper Level - 586 sq.ft - (Dense packed cellulose)
Basement - 1,179 sq.ft - (2 inch EPS Foam followed by 2x4 wall with unfaced fiberglass)
Attic - blown cellulose - R44

In Mechanicals | Asked By Ben Thrush | Aug 15 16
11 Answers

Looking for design software recommendations

Hi -

I'm a new member and I'm looking for recommendations for relatively easy-to-use design software (I did try searching the site but didn't find anything discussing that). My first task will be a simple floor plan so I can ask the good folks here for advice on placing mini-splits. Further down the road, I'd like to be able to draw out details for roof and wall assemblies for the retrofits I hope to do. Any then maybe a tiny house (or at least a tiny shed) in the future.

In General questions | Asked By Nickolas Van Kleeck | Jul 23 16
1 Answer

Anyone have experience with Kohltech Supreme triple-pane windows?

I am considering Kohltech windows for my home build and am comparing them with tri pane Integitys. The have simmilar performance values but the Kohltechs are much cheaper. This is great, but also scares me a little since I have seen Integritys but not Kohltechs. Can anyone speak to their quality? Thanks for the help!

In General questions | Asked By Tim Burke | Aug 13 16
2 Answers

Cardboard insulation baffles have fallen down

Hi Pro Team!

I live in a solar (PV and HW), energy star house, built in 2005, in Washington, DC.

I was in the attic today and noticed that some of my cardboard insulation baffles had fallen over. I'd estimate about 1/3 of them. I don't go into the attic frequently, so they could have fallen over up to a few years ago.

Does this pose a problem?

Any guess on cause? Wind gusts blowing through the soffits knocking them over? Age (cardboard becoming less rigid)?

Thank you!

In GBA Pro help | Asked By Michael Harris | Aug 14 16
4 Answers

Fascia/soffit at held down gable

I'm trying to figure out how to frame the subfascia and soffit returns on a roof with the gable trusses held down 5.5". I don't want to do a wide fascia across the whole building, so right now I am planning a boxed return that steps up at the inside edges of the gable trusses, but I'm not completely sold on this solution. Does anyone have an explanation or images of how you have handled or would handle this detail? I am open to all suggestions. Thanks!

In GBA Pro help | Asked By Jim Tyler | Aug 12 16
1 Answer

Should I use this foam?

I recently got a bunch of polyiso foam pieces that I want to use on the outside of my house. The outside of the house has 4" of foil faced polyiso, but I have many attached porch roofs that have nothing between the rafters where they attach to the house. I was going to cut and cobble pieces in these spaces and can foam the edges. Here lies the issue, the foam I just got is 3" thick so I was going to double them up but I'm not sure about the facing. One side is a layer that looks like tarpaper and the other side looks like 1/2" of sound board, seems similar to suspended ceiling tile material.

In Green building techniques | Asked By darren williams | Aug 13 16
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