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17 Answers

Insulating a crawl space

We have a single level ranch style home with crawl space that connects with the basement living space. The crawl space is located at the end of the ranch home. This crawl space has a vapor barrier over the rocky dirt floor, originally installed as part of radon remediation. The concrete walls in the crawl space contribute to cold air and possibly some moisture. At this point, though, I think that it is safe to say that no water seeps through into the crawl space.

In Green products and materials | Asked By william phillips | Feb 24 12
18 Answers

Please explain radiant barrier comments

Quoting from "Radiant Barriers: A Solution in Search of a Problem":

In Green products and materials | Asked By John Mattson | Sep 29 11
3 Answers

Open-cell SPF in an attic with no vapor barrier

Hi,

I live in Pittsburgh and am doing a renovation of an old home. I'm doing a lot of the work so far myself, with the help of my father. At the same time I've been working with an architect to figure out the overall project. And there is disagreement between my two spheres on how to insulate the attic.

The (hopefully) key points: it's currently a vented attic, I'm going to be putting HVAC and ductwork in that space.

My father is recommending I keep the attic as vented, put down batting on the attic floor, and do various things to ensure the HVAC unit is leak free and insulated

In Energy efficiency and durability | Asked By Will Oberman | Feb 26 12
12 Answers

Insulation help

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

Opinions on "quartz" countertops?

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

Best way to insulate attic that will have storage space

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

Has anyone been successful in fighting their city on not putting insulation on interior brick walls?

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

Our house was built using salt water

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

Retrofit rigid foam outside CMU walls

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

Am thinking of the following wall and roof assembly in BC as a cost effective way to achieve a high R-value and tight envelope.

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
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