Q&A: A Forum for Green Building Experts and Beginners

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12 Answers

I am planning to build a 32x40 garage, gambrel trusses with a bonus room in the second story. I also plan to have radiant floor heat in the slab and in the joists to the bonus room. I live in Mid-Michigan.

My question is what is the best way to insulate. I would like to spray foam a portion of the building (roof/ceiling) and conserve costs by going with batting on the walls. I am having 2x6 construction on the walls which will give me some extra room there.

In Energy efficiency and durability | Asked By John Matousek | Feb 23 12
5 Answers

OK, so whats's greener... a granite slab, or a quartz slab from a company like Silestone, Ceasarstone, etc? It looks like the manufacturers are using "quartz" (where does that come from?) along with resins and dyes to make their product. On the face of it, it sounds like it might be less environmentally harmful than quarrying blocks of granite and shipping them around the planet. Any thoughts?

In Green products and materials | Asked By David Meiland | Feb 26 12
3 Answers

I live in a 1921 brick and stucco house in climate zone 5a. It has a gable roof with 2 large shed dormers (1 front, 1 rear). Attic floor joists are 2x4 with blown insulation which is spotty in areas, meaning none. Roof rafters are 2x6. There is an air handler with one large return and 3 ceiling grills (1 in each bedroom ceiling) Gable end walls are clay block with stucco on exterior. Dormer walls are framed with stucco on exterior, plaster/lathe interior and no insulation. Dormer walls on gable ends are balloon framed.

In General questions | Asked By Jonathan B | Feb 18 12
8 Answers

We live in MN. We have an 1891 clay brick home. The bricks are dual layer about 13 inches thick and made of clay. The brick is the load bearing walls and the floor joists are in the brick walls. We were originally thinking of spray foam, but after reading the article, we are very scared that if we put any insulation our brick will have freezing & thawing and deteriorate. We have gutted all of the walls of the lath and plaster, so we have access to insulate, but do not want to ruin the brick. We would like to appeal to our local building officials so not be required to insulate.

In Energy efficiency and durability | Asked By Kristina Beedle | Feb 24 12
4 Answers

Does the salt water make any bad effect on walls and iron rods used in concrete ?
if so how to control it?

In General questions | Asked By madhura mohanraj | Feb 24 12
6 Answers

I'm looking for resources to plan a retrofit of rigid foam insulation outside our walls. The vast majority of resources are about wood framed walls, but we have walls built from concrete masonry units (CMUs).

In Green building techniques | Asked By James Howison | Feb 21 12
29 Answers

2x6 structural wall with roxul in the cavities and gaps in sheathing (drill holes as well) to promote drying to exterior. The inside of this wall is sheathed with 1 inch of polysio (air and moisture barrier). A 2x4 wall inside this provides chase services, a cavity for fiberglass batts, and protection of air barrier.
The 2x6 walls are straightforward construction, with most of the building wrap and rainscreen installed before lifting wall. Foam insulation is also easy to install with no penetrations.

In General questions | Asked By Reggie DuBois | Feb 14 12
6 Answers

Newbie here with a design question. Planning a retirement home about one hour west of Ft. Worth, TX, (Gordon,TX) climate 3B I believe. Having trouble with the proper unvented roof design using, as I'm told by most of the approved builders in my development, open cell sf (spot leaks if any develop). What are my most practicable, cost efficient methods of :

1) achieving my required R code value in the roof (R38 roof/R15 walls per USDOE website)
2) eliminating thermal bridging (if that is a concern in climate 3B?)
3) Use ADA air sealing of sheetrock

In Energy efficiency and durability | Asked By John Grutta | Feb 21 12
15 Answers

Let me start by saying that I am sorry this is going to be such a long post. But I have spent countless hours over several winters now trying to assess this problem. And I guess I feel that for any of you to be able to give me an informed opinion as to the cause(s) of my problem and any subsequent suggestions/solutions, I have to give a thorough explanation of the project background and site conditions. I’ve also attached a few photos to help visualize the situation. And so I come to you GBA experts, on bended knee, in the hope that you can generously impart some of your wisdom.

In Green building techniques | Asked By Christopher Fuller | Feb 17 12
3 Answers

We recently built an addition onto our house and instead of extending our existing AC-only system, we installed a second AC/heat pump system. The house also has an oil-fired boiler with baseboards.

We added two heating zones to the addition onto the existing hydronic heating system, so the addition has two heat sources - oil and heat pump.

In Energy efficiency and durability | Asked By Eric Yancey | Feb 21 12
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