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1 Answer

Insulating a Cape roof

Hi All,

I've been upgrading the insulation in the house, and have noticed that the roof insulation in my cape is only R-19. I believe code here in Massachusetts is R-38. The rafters are 2x8. There are soffits, but no air channels up the roof -- just R-19 batts shoved in there.

What are my options for getting to R-38? Not fiberglass, I'm pretty sure!

I'm looking for education on all my options before deciding what to do.



In Energy efficiency and durability | Asked By Alex Jones | Jan 10 14
7 Answers

New home — attic moisture

Our 2 y/o old home has had moisture issues in the attic since we moved in. It's a Cape-style home with closed-cell foam insulation and touted as a "tight" efficient home.

In General questions | Asked By Brian Peck | Jan 8 14
3 Answers

How efficient is ceiling radiant heat?

I'm considering renting an apartment with ceiling radiant heat, and wondering if it's cost effective.

In General questions | Asked By Lynne Pifer | Jan 8 14
9 Answers

Installing rigid foam on a bedroom ceiling for increased efficiency

Is it possible to install rigid foam over my existing plaster ceilings to decrease the heat loss in a bedroom? I would be looking to install tin ceiling over the rigid foam for a fire barrier (and aesthetics). The attic has approximately r50 of cellulose already and I’m finding the room isn’t holding temperature very well at all. I keep the house at a baseline temperature with the heatpump and use electric heat in the bedroom to supplement. Once the electric heat kicks off I find the room temperature drops very quickly.

In Green building techniques | Asked By Mark McGraw | Dec 9 13
1 Answer

Rim sill insulation — don't want spray foam

Connecticut weather
Insulation and ceiling removed in basement. Ready to insulate and sheet rock.
Concerned about out gas of spray foam.

What is best most economical insulation for rim sill? Planned to use Roxul safe and sound for ceiling. Any thoughts?

In General questions | Asked By Mary Ann McCandless | Jan 9 14
3 Answers

PERSIST building method

I am reconsidering using OBS faced SIPs for wall/roof construction in climate zone 5A (Rochester, NY). The building design is 1500 sq. ft, frost-protected, slab-on-grade - monolithic pour. Shed roof, one floor plus loft.

I am interested in the PERSIST building envelope method but am having trouble locating construction method details.

For instance:

1: What is the best choice for exterior insulation? How is it attached to exterior sheathing? How is it laid out (pattern) and sealed?

2: What is best choice for exterior sheathing? Material? Thickness?

In General questions | Asked By David Mancuso | Jan 7 14
0 Answers

Do you know of a qualified installer of APEX block for a project in CA?

Location: Upland, California.

Project: 2-story 3,400-square-foot commercial building, new construction.

In GBA Pro help | Asked By Dale Cummins | Jan 8 14
1 Answer

How to insulate my roof... no attic

How to insulate my roof... no attic

In General questions | Asked By Todd Clem | Jan 8 14
2 Answers

Radiant barrier on the attic floor, on top of the insulation?

I received the question below from a friend of mine living in the Central valley of California. Living and working in the Pacific Northwest I don't have any real world experience with radiant barriers. Any thoughts...?

What is your opinion regarding radiant barriers in residential attics? We have a quote from a contractor for 80 cents/sq ft. – which is approximately $2,500 for our house. His system involves laying rolls of the radiant barrier directly on top of the attic insulation. We have a whole house fan, so would a radiant barrier provide significant additional savings? Your thoughts?

In General questions | Asked By Shawn Ellsworth | Jan 8 14
1 Answer

Builders and architects for passive houses

We are trying to build a passive house in South Indiana and will attempt to source high insulation precast concrete walls, tilt and turn windows, and recycled plastic roof shingles or other green roofing materials.

In Energy efficiency and durability | Asked By M Pink | Jan 8 14
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