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12 Answers

Wall assembly for an old church in Vermont

A client has an old un-insulated church in Central Vermont. She want to insulate the whole thing and turn it into a house. The builder wants to do this wall- assembly. I am concerned about dew point issues and trapped moisture. The walls are currently 2x5 studs with no insulation. Thoughts?

Asked By Robert Swinburne | Apr 18 18
0 Answers

Open cell vs closed cell in a basement?

Hi All!
I am looking to insulate the basements worth of band joists in Northern Vermont (climate zone 6A). There's a couple different things going on here and I want to be sure I'm not goofing it up.

Asked By David Bailey | Apr 19 18
2 Answers

Thermalbuck Insulated Window Bucks

A person on my thread about Roxul Comfortboard vs ZIP-R Sheathing suggested that I use this insulated window buck when using the Roxul system. I never knew this type of product existed, but I think they deserve their own thread.

Anyone have experience using them?

Asked By Scott Wilson | Apr 17 18
2 Answers

Ceiling insulation

I live in South Florida and have an uninsulated open ceiling in a laundry room that used to be an outdoor laundry, it has since been surrounded by a finished living area. It is open to the roof with 6” trusses on 16” centers. The room has a block wall on one side and stud walls to the ceiling on the others so there is no way to vent the space from eaves to ridge. It gets very hot in there and I want to insulate and drywall the ceiling. Should I fill the joist space with insulation or should I leave a gap between the insulation and the roof deck?

Asked By TomProud | Apr 18 18
21 Answers

Roof underlayment for vented roof with standing-seam metal roofing

Im nearing the end of construction of a high efficiency timber frame hybrid house I'm building for my self and have a low slope roof question that I would like some opinions on. Roof pitch is 1.5/12 (7 degrees)

Our main roof structure consists of timber rafters, 20" I-joists, dense pack cellulose, 1/2" plywood sheathing taped to the walls as air barrier. We drilled holes all over the roof to dense pack the cellulose from above (as our interior finish was installed on top of the timber beams as soon as they were installed.

Asked By Scott Benson Climate Zone 7A | Apr 9 18
9 Answers

Does my wall assembly seem adequate for my area?

Hi everyone! I have a question about a wall assembly I want to use at my off-grid mountain cabin. It's a 1986 build cabin but the weather and environment with a lack of previous owner's attention have made the project list somewhat large. We're overhauling our solar system so I plan to practice these wall assembly details on the powerhouse shed before attempting the main cabin.

Here's what I have planned:
1) interior insulation currently fiberglass, want to install closed cell spray foam in some areas and leave fiberglass in other areas
2) 1/2" CDX plywood
3) Delta vent SA WRB

Asked By mountaincabin | Apr 17 18
13 Answers

How to insulate underside of roof deck in 1927 conditioned space

I have lived here for 18 months. First thing I did was re shingle to roof. Roofer is a pro and said decking was in great shape. Shingles are mid-dark gray in color. This is a 1.5 story home in central MN with the second story "finished" at some point with Homasote on the walls and ceilings. Homasote is a brand name associated with the product generically known as cellulose based fiber wall board, which is similar in composition to papier-mâché. It is in bad condition and needs to come down. There are two unfinished spaces behind knee walls that are accessible.

Asked By Mindy Jost | Apr 13 18
7 Answers

Does Reflectix "Big Bubble" insulation really achieve R-6?

I have seen several discussions here about bubble wrap insulation for ducts (some links below). However, they are all a couple years old, and they don't seem to directly address one of Reflectix's products. The older and smaller products were generally met with great skepticism because they claimed high R values without clarifying that the installation required an air gap between the duct and the bubble wrap.

Asked By huhnra | Apr 16 18
5 Answers

Roof ventilation

I have a low pitch (1/12) single slope shed roof on my house. (Marine Zone 4c near the coast with very little snow and ice) The framing is 2x8 filled with insulation. Drywall on bottom and skip sheathing on top- no ventilation. The existing roofing is built-up asphalt.
I plan to remove the built-up roofing and install 2" of polyiso, then 1 and 1/2 inches of EPS, 5/8" of plywood, then a standing seam metal roof with mechanically seamed joints.

Asked By EASimonsen | Apr 14 18
2 Answers

Insulating a Non-typical Cathedral Ceiling

Insulating a normal cathedral ceiling has been covered by GBA in Martin Holladay's How To Build an Insulated Cathedral Ceiling .

Asked By Steve Robertson | Apr 13 18
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