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3 Answers

Spray foam in cathedral ceiling

I'm building in zone 5 with 2x10 roof rafters. Do you see a problem using 2" closed cell on the underside of the roof sheathing with the remainder of the cavity filled with open cell in order to achieve the code required R-38?

In Energy efficiency and durability | Asked By Scott Schaub | Dec 30 13
3 Answers

Exterior insulation in MN attic

I have two walls of a bedroom that are adjacent to my garage attic. I am hoping to beef up the insulation on the outside of the wall in the attic. I am worried about a few things - cost, installation, and moisture issues.

I have a 2x6wall , FG batts, with vapor barrier on the inside - so wouldn't be in for something that is too vapor resistive on the outside (i think?). Currently the wall on the exterior is sheathed with vapor permeable fiber sheathing (Brace-rite,28perms). I was under the impression that xps or polyiso wouldn't be advisable...

In Energy efficiency and durability | Asked By Nick T | Dec 29 13
1 Answer

Blown/Compact Rock Wool

I live in Juneau, Alaska. Being in a Temperate Rain Forest (220+ days of rain per year), both rain and cold is an issue. I would like to retrofit my exterior walls and blown cellulose seems like the most effective way per dollar spent. However, Rock Wool seems like an even better choice since it provides better fire resistance, moisture resistance, and a similar R-value.

The problem is that I can not find any USA granulated Rock Wool. I find plenty in the UK and New Zeland, but nothing in the USA.


In Green products and materials | Asked By Emil Mackey | Dec 30 13
1 Answer

Solar water heating: can someone recommend a good resource for high water demand projects?

I'm reviewing a document that quasi-recommends solar water heating (SWH) for projects with large water supplies such as dorms, dining facilities, laundry facilities, etc. I've not worked on any projects where SWH is used, so I'm a little behind the learning curve on this one and most of the material I'm able to find talks about SWH in residential applications.

In Energy efficiency and durability | Asked By Jennifer DeWitt | Dec 29 13
1 Answer

Basement corner frame around electrical panel question

So I'm looking to finish a space in my basement. The space has an electrical panel near a corner of the concrete walls. I am putting up 2" rigid foam on the concrete and that will leave me 2 1/4 inches to the edge of the panel. What is the best way to frame that corner? If the panel has to be moved then that would also require extending about a dozen wires coming out of it that run to various locations in the house so it would be nice if I didn't have to move the panel.

In General questions | Asked By Wade DeWerff | Dec 29 13
5 Answers

How to insulate ceiling and walls in zone 3 - new construction?

I am in the framing stage of a new house near Raleigh, NC (zone 3). Our strategy for an air barrier is to rely upon placing the air barrier on the outside at the sheathing using the Zip system on all walls and the roof with all seams taped. The house is situated on a concrete slab that is insulated with rigid foam (R-5). The sill plate is air sealed using Protecto-Wrap sill sealer gasket. Our plan (right now) is to insulate the walls using fiberglass batts (2x6 walls).

In Energy efficiency and durability | Asked By David Harris | Dec 28 13
3 Answers

When placing an exterior wall on a slab floor for a single-story house, what is code for sealing where they are contacting?

I have been told all is needed is to line the bottom plate with Acusta seal, running either 2 beads along the bottom plate or in a criss-cross pattern.

In Building Code Questions | Asked By Vincent Rempel | Dec 28 13
1 Answer

Insulating a prefab house

I have a Wausau prefab house in Minnesota. The walls and ceilings are panels and everything is glued together. I am thinking of using furring strips on the exterior walls and ceilings on the interior of the house and adding some 2" foam insulation, vapor barrier and then sheet rocking over this. Any thoughts or ideas on a better way of adding some insulation?

In Energy efficiency and durability | Asked By Rod Elbert | Dec 29 13
1 Answer

Confused about insulating a kneewall attic space

I am confused with all the different options concerned with insulating a kneewall attic space in my Cape Cod home. Presently, there is insulation on kneewalls (fiberglass R-13). There is no insulation on roof deck boards or baffles. There are soffit vents and a ridge vent.

The room is extremely hot in summer and cold in winter. What are the best options aside from spray foam to make this area of my home more comfortable and energy efficient?

What about the following:

1. Blocking under knee wall to stop air infiltration under floor and downstairs ceiling?

In Energy efficiency and durability | Asked By TIM GABRIEL | Dec 27 13
1 Answer

Will stucco adhere to peel & stick membranes?

Trying to do a window detail that involves some peel & stick membrane but the question I have is whether or not EIFS/synthetic stucco will adhere to peel & stick or does one have to install EPS over the peel & stick and then stucco?

In GBA Pro help | Asked By Peter L | Dec 27 13
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