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39 Answers

3-D Networks, Premature Shingle Failure and Ant Farms

In Energy efficiency and durability | Asked By John Brooks | Dec 17 11
3 Answers

Is Spray Polyurethane Foam prudent in this application?

I am renovating a 115 year old building in Denver, Colorado. The structure is triple-wythe solid-bonded very soft masonry. (See the attached photo.) I'd like to apply Spray Polyurethane Foam on the interior side of the wall and then overframe and drywall. (I can't do anything to the exterior because the facade is landmarked.) I have two concerns:

1) That moisture which enters the wall from the exterior will not be able to get out and could cause laminar separation of the masonry due to the freeze-thaw cycle.

In Green building techniques | Asked By aaron tweedie | Jan 19 12
3 Answers

Dense pack 2x4 walls with cellulose

My question/concern is regarding the best approach to take given the following information. I have a 1950's era home built with 2x4 walls. I discovered there is no insulation in the walls, but there is what appears to be a radiant barrier made up of two layers of foil with pleated paper between.

In Energy efficiency and durability | Asked By Cameron Clark | Jan 30 12
7 Answers

Using SPF in a plastered wall.

Can you give me the pro's & con's of having SPF used in any already plastered wall? These wall would either have very old insulation or none at all.

In General questions | Asked By David Nehring | Jan 30 12
3 Answers

An air exchanger type product from Musty Basement Solution

There are several air exchanger type products on the market. The one I am most familiar with is Musty Basement Solution, and happy to sing its praises.

A friend of mine raise a concern regarding if the machine pulls hot air out of the building thereby wasting heat. My question is, if that is true and if so how much heat is lost, and how would that loss compare (objectively) with the gains?

In Green products and materials | Asked By John Trumbull | Jan 27 12
5 Answers

Spacing of studs in Advanced Framing more than 2 stories

I am building a 1 1/2 story home and am using advanced framing. I hope to stack all my framing using 2x6" studs 24" on center. Only problem is we have a walk out basement. The framing on the downhill side is: basement 82" high, 1st floor 8', 2nd floor 5' 2". If I read the IRC code right (mine is 2003), section [602.9] says cripple studs in the basement greater than 4 feet high are considered an additional story. And then in Table 11 for stud spacing [602.3.1], don't I have to consider my home as Roof & ceiling + 2 floors? That requires 2x6" framing to be 16" on center.

In Building Code Questions | Asked By tom ruben | Jan 30 12
7 Answers

Rigid foam ceiling question

I'm building an ICF home in WV. I have my roof trusses on 24" centers, 2x4 bottom chords, and 9'7" from the floor to the bottom of the truss.

I would like to use rigid foam board for insulation and I'm wondering if it would be possible to use long screws with washers (Wind Lock) to screw through 6-8" of foam into the truss? Cover it with an acrylic stucco and fiberglass mesh system.

In General questions | Asked By ray conrad | Jan 29 12
6 Answers

Wall construction material and sequence

I am at zone 3B - little rain/wind only in the winter months with no snow. I plan to use the following wall assembly for stucco wall from inside out:

Dry wall
Cellulose insulation / 2*4 wall
Building Paper layer 1
Building paper layer 2

A few questions:
1. My contractor is trying to tell me that I don't need 2 layers of paper. What would you tell a contractor who is not familiar with green building to make him comfortable with this extra layer of building paper?
2. What type of building paper should I tell him to use? He said that there are many types.

In Energy efficiency and durability | Asked By Rian Bart | Jan 26 12
4 Answers

"Healthier" HVAC materials

We are installing a new HVAC system. We are chemically sensitive and would like to use products that do not off-gas, if possible. Does anyone know of a healthier substitute for neoprene duct connectors, and standard duct tape or mastic? Also, we would like suggestions for a healthier duct insulation material. It is difficult to find such products. Green does not necessarily mean healthier, as we all know. Thanks!

J. Thurber

In Green products and materials | Asked By Jas Thurber | Jan 30 12
3 Answers

Adding rigid foam over existing insulation

I like in northwestern North Carolina (zone 7) in a Cape Cod style house. The upper rooms are pretty uncomfortable in the summer. You can feel the heat radiating into the room I presume because it basically has "attic" on three sides that is unconditioned space. There are seven foot-high knee walls on two of the three interior walls in each bedroom with a bath in the middle. The knee walls have fiber glass batt R-19 which sits just proud of the 2X4 stud bay.

In Energy efficiency and durability | Asked By Donald Guilbault | Jan 29 12
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