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6 Answers

Why I am Locked Out of This Site

This seems to happen frequently even though I am a pain member. It is a real pain in the butt...

In General questions | Asked By Woody McMahon | Jan 26 14
3 Answers

Will I rot out my plywood roof decking if I condition my attic space?

Will I rot out my plywood roof decking if I condition my attic space? I have a standing-seam metal roof with 15 lb. felt paper as an underlayment. I am in a coastal climate on the Puget sound in WA state (marine zone 4).

I am considering a conditioned attic space in my home that I am remodeling. We want to use the space for storage and a play space for the kids. I am certain the interior space would have sufficient ventilation from the HRV.

In Energy efficiency and durability | Asked By mathew BEAN | Feb 11 14
3 Answers

Wood shingle roof and an energy retrofit

I have a wood roof to replace on a 300-year-old house in a historical district. The house is also in serious need of an energy retrofit.

Wood is more expensive (the HD Commission has a record of approving asphalt based on cost, so it is a choice), but may provide options not found with asphalt or other coverings, since, by design, shingles and skip sheathing must dry to the outside; sheathing condensation issue evaporates.

Any thoughts/research about how to best use this advantage?

In Green building techniques | Asked By Everett Hyde | Feb 10 14
23 Answers

How to do footings without concrete

We're looking to build a shed and a workshop in our backyard highlighting sustainable approaches. The buildings will be one-storey, mainly timber, used for some woodworking equipment and general storage so light loadings.

We're in an area with reactive clay so the common building approach is to use concrete as footings.

Ideally, for site access and other reasons we would prefer to use minimal concrete.

But what else could we use for footings?

Ben Law has used stone.

In Green building techniques | Asked By David Coote | Nov 9 12
7 Answers

Best rigid insulation to add to exterior of existing 2x6 wall with poly vapor barrier?

As part of replacement of T1-11 siding with fiber cement on a building in Zone 6A, I plan to add 2 inches of exterior rigid insulation outboard of existing 5/8 inch plywood sheathing and additional sheathing on the exterior of the rigid insulation as a nail base for the fiber cement. I expect to use some type of rain screen between the new sheathing and the fiber cement.

The existing wall is 2x6 framing @ 24 inches o.c. with R19 fiberglass insulation and an interior polyethylene vapor barrier that must remain in place under the interior gypsum board.

In Energy efficiency and durability | Asked By Al Russell | Feb 9 14
2 Answers

Window details

We're taught to air seal the interior side of a window with foam or tape. We're also taught to provide some sort of back dam or positive slope to the sill.

What is the point of sloping the sill to the exterior if the window is foamed/taped/caulked to the framing? We are also taught to not caulk/tape the exterior nailing flange to the housewrap for the same purpose, i.e., give water a path to escape.

What gives?

In General questions | Asked By erik olofsson | Feb 10 14
10 Answers

ICF home with elevated radon


Here's my situation:

- 2150 SFT ICF ranch with full basement (partial walkout) in East-central Illinois with EIFS siding.
- Exhaust-only ventilation thru 3 bath fans (2 on the main floor plus one in the basement that we rarely use) and we can feel the fans struggling to get the air out due to tight ICF.
- Large windows on the pond-side that are double-paned but we can feel cold air drafts on the insides of the window sill sides. When I complained about this, the builder sent me some foam stoppers to install for the winter time which seems to help some.

In General questions | Asked By Venkat Y | Jan 23 14
7 Answers

Super Insulated Hot Water Heater - Math Verification

I own an electric 40 gallon dual element hot water heater. Based on information received from the manufacturer here are the specifications:

47.25 inches height
20 inches diameter
24.98 sqft total surface area
2 inches of foam valued at R-16

My water temp is set for 120, ambient temps in the basement are 54F, though the floor can be cooler than this (48-52F). I used the conductive heat loss equations shown here (http://leaningpinesoftware.com/hwpipes/hot_water_heater_tank_insul.shtml) to calculate a loss of 264 kwh/year in standby losses (~$29/year at local electric rates).

In Energy efficiency and durability | Asked By Christopher Tomasso | Jan 30 14
11 Answers

Polyisocyanurate insulation — rip off?

Our radiant engineer strongly warned for the use of polyisocyanurate. I see that long term R-value ends up around 5.6. When this is true, why is this not mentioned on every page where polyisocyanurate use is mentioned... Our engineer REALLY dissed the product as he mentioned that the R-values decrease WITH temperature decrease. Exactly when you need it to work: it will NOT. "A total waste of money, stay away from it!" were his words. True or false? Simple styrofoam, when not used under slab, is just fine. Same R-5 per inch as Double Density...

In Energy efficiency and durability | Asked By Jan Verschuren | Jan 16 14
1 Answer

Spray foam that is environmentally conscious and can be recycled at the end life of the product?

I need a spray foam that is chemical free and environmentally friendly. It must be sand-able and/or sculpt-able in some way. It does NOT need to have very good insulation qualities because it is being used solely in a temporary interior installation. The idea is to sculpt a brick wall texture into it and use this as a cheaper, lighter, and recycle-able alternative to actual bricks. Color and texture is not important as well.

Thank you my fellow enviro-conscious minds!

In Green products and materials | Asked By Sarah Stypulkoski | Feb 9 14
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