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1 Answer

Has anyone used EcoFoil or radiant barrier/insulation in basement?

We are trying to protect our concrete basement from moisture. We were thinking about putting EPS foam on the floors and walls as a thermal and vapor barrier. We still may go that direction, but I am concerned about our daughter's chemical sensitivities and the flame retardants in the foam. Has anyone used a radiant barrier like EcoFoil on the walls and concrete slab (under laminate)? Here is a link to the product: http://www.ecofoil.com/All-Products/Concrete-Insulation.

In Green products and materials | Asked By Carolyn Farrow | Feb 21 16
13 Answers

Retrofit insulation and some kind of rainscreen

I read 36231/retrofit-insulation-walls-no-sheathing-or-wrb Our house is very similar (including being in Portland!) - original wood siding, no sheathing, no insulation, then studs that are 16" OC (variable). Also balloon. But we have made a preliminary hole in the plaster and when it rains hard, the siding gets soaked (the rain hits this side of the house). We plan to strip exterior walls to the studs in order to insulate.

In Energy efficiency and durability | Asked By Catherine Buck | Jan 9 16
6 Answers

LED panel lights for residential use?

Will LED panel lights (or luminaries) be one step closer to the holy grail of residential lighting? Currently, these lights are offered in sizes that will fit in commercial ceiling grids, e.g. 2' x 2', 2' x 4', 2’ x 8’, etc. They are typically less than 1/2" thick excluding the LED driver that may or may not be attached directly to the fixture. As Martin noted in Rule 2 on his 10 Rules on Lighting, it’s better to illuminate the ceiling than the floor. Mounting these large format panels directly to the ceiling illuminates a much larger area than any point source or fluorescent lamp could.

In Interior design | Asked By Steve Robertson | Feb 19 16
3 Answers

Can I use rigid foam above roof sheathing and closed-cell spray foam below?

I'm going to be re-roofing my house (when the weather gets a bit warmer), and feel this is a good time to upgrade the insulation. Here are the particulars of my house:

I live in climate zone 7.
Cathedral ceilings in most of the house.
True 2x8 rafters.
Low slope roof - modbit.

In Energy efficiency and durability | Asked By Edward McLean | Feb 14 16
1 Answer

EIFS in combination with interior spray foam insulation

I would like to design a wall system using EIFS stucco with an interior spray foam insulation. I live in north east Colorado which is in climate zone 5. The EIFS eps would probably be 1.5" over Tyvek stuccowrap wrb, or a similar product. My wall sheathing is 7/16 osb.

On the interior, my walls are 2x6. I would like to apply 1" closed cell spray foam followed by a kraft faced insulation bat of either R-13, which would leave about .5" of an air gap between spray in and fiberglass. Or R-19 kraft faced fiberglass which would come in contact with the spray in foam.

In Energy efficiency and durability | Asked By James Neb | Feb 20 16
2 Answers

Roof ridge vents?

I have a Cape built in 1945 in Queens New York City. My roof is 35 years old and I want to replace it. The second floor of my home consists of (2) bedrooms and a foyer. Roofing companies tell me they will cut my roof to install a ridge vent. I do not have an attic and I fear this will actually make the living space colder. Any advice?

In General questions | Asked By eddie gates | Feb 20 16
18 Answers

Can HOA make me use replacement windows that don't meet current code?

I recently replaced all windows in my condo (22). I thought that I had HOA approval, but I never thought to tell the HOA that I was getting energy efficient windows. (U-Factor of 0.41, SGC of 0.27). These have a greenish tint. My HOA wants me to replace them again with clear glass as they green tint is not in keeping with the community.

I don't think that I can replace with clear glass and meet current building code (California). Especially since I had to use aluminum frames instead of vinyl to meet the HOA requirements for frames that match the community.

In Building Code Questions | Asked By Joseph Burke | Feb 18 16
8 Answers

Roof clips

Our roof will be 12/12 pitch with 2x6 raifters,would it affect much if we changed to 2x8 to fit a little more insulation,also our roof deck is 7/16 osb taped with a 1.5-2 inch polyiso nailbase on top if that,do you think we need roof clips on the first layer of osb or need to change that to 5/8osb?

In General questions | Asked By Quinton Bryant | Feb 11 16
1 Answer

Passive radon system design for crawl space sub - membrane suction

I have a 27 x 36 foot rectangular crawlspace that has bare dirt floor. It reads around 30 when I conduct tests for 48 hours.

I want to place 191' of 2" ID ABS irrigation pipe in crawlspace in a grid pattern with 4 cross laterals. I was going to run a 5" solid ABS plastic pipe from CS floor to most top place on roof, that's 22' of vertical rise of a 5" plastic pipe.

Temperature under the membrane is 42 deg F coldest Winter (frequently around 50), and about 50-55 deg F at hottest in Summer.

In General questions | Asked By Andy Nels | Feb 20 16
3 Answers

New take on double stud wall

Martin, please don't sigh. After reading your last article, I couldn't help thinking about another way to build a double stud wall. The only reason I'm heading down this road again is because I'm trying to cut costs while keeping the building process relatively simple. The drawing attached below essentially uses the exterior wall's studs as the furring strips for the siding. Something I thought would be a benefit for providing a nice flat sturdy surface to attach our hardie plank siding.

In Energy efficiency and durability | Asked By Brian W | Feb 19 16
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