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29 Answers

European windows vs. North American windows

I have read many blogs and Q&A pages from this web site and I am still somewhat confused about European windows.

In Energy efficiency and durability | Asked By Steve Young | Sep 5 12
3 Answers

Is 5/8 drywall sufficient to support R-60 cellulose in a ceiling?

Is 5/8 drywall screwed and glued 24" on center sufficient to support R-60 cellulose in an attic ceiling?

In Green building techniques | Asked By Michael Arnold | Sep 26 12
12 Answers

How to make a large concrete block lighter?

I am planning on using a 12" H x 18" D x 20' L concrete block as the Hearth of a contemporary wood burning fireplace. The problem with using such a large unit of concrete is the weight of the block. I was thinking of using a high density Polyisocyanurate or Polyiso foam block in the center of the form to take some weight out of the Hearth. I am not sure going with route will cause me any problems down the line and would appreciate any comments you might have.

In GBA Pro help | Asked By dennis levine | Oct 24 11
3 Answers

Insulation material to attach to garage ceiling

Our 20 year old Ecco house has been compromised (by a previous owner) due to a garage having been dug out underneath. .we are therefore looking for a very thin but Ecco effective insulation material to attach to the ceiling. there is no room to create a false ceiling to contain any such insulation.

In Green products and materials | Asked By Linda Wright | Sep 25 12
1 Answer

Variable-speed compressor v. two-stage compressor

Building a house in Austin, Texas, and would like (1) a five-star green rating from the city and (2) a central AC with a variable speed compressor. The only problem: the system we're looking at only comes in 1 ton increments. We need 3.5 tons to meet the city's ratings requirement of square feet per ton (and a 3 ton system won't be enough cooling for the house). Therefore, we (may) have to go with a two-stage 3.5 ton system.

My question: Does going from a 4-ton variable speed compressor to a 3.5 ton two-stage compressor make sense energy efficient-wise?

In Mechanicals | Asked By Robert Mace | Sep 25 12
1 Answer

Housewrap question - replacing siding

I want to replace the siding on my house. It has wood (plywood) siding sheets on it.

I notice that it don’t have any housewrap. When I pull back the siding, I can see the installation. When I watch at some video about housewrap, they are tacking it to a type of plywood.

My question is, do I need to install the plywood are something before I put the siding on it? I need to know what is best, and what do I do when I get to the windows and door with the wrap. If you have any related videos send them to me.
Thanks
Myles

In General questions | Asked By Reginald Myles | Sep 25 12
7 Answers

Is poly vapor barrier needed under blue foam in cathedral ceiling?

I have a small building with a loft under a cathedral ceiling.
I'm insulating the cathedral ceiling with two layers of 2" blue board foam between the 2x6 rafters and one more layer of 2" foam on the underside and perpendicular to the rafters (making 6" total foam thickness - R-30)
I have cut the blue board between the rafters a bit small and sealed around all edges with "great stuff" expanding foam.
I have a 1.5" ventilation space between the top of the insulation and the bottom of the roof sheathing connecting my eave and ridge vents.

In Energy efficiency and durability | Asked By d c | Sep 24 12
1 Answer

Has anyone seen a damper for a gas fireplace pipe?

In our current house the gas fire places get quit cold during the winter unless we leave the pilots on. We are planning a new house and wish to include gas fire places, but the new ones seem to be pilot less. So I’m looking for a way to eliminate the cold outside air moving freely through the firebox until a fire is lit.
Perhaps a damper that closes off the center "hot" pipe.

In Energy efficiency and durability | Asked By Paul Huntman | Sep 25 12
9 Answers

What barrier should I use under wall shingles to increase insulation in a single wall cabin?

I have a 100 year old redwood cabin in Northern California in the coastal area.

It is single wall construction consisting of 1x12 redwood boards and framing visible on the inside, and with cedar plank covered by redwood shingle on the outside.

I am replacing the shingle and will be repairing damaged cedar plank as necessary.

I do not want to turn the cabin into double wall construction with interior insulation as it will wreck the character.

In addition to building paper, what can I use between the ceder plank and shingles to increase the energy efficiency of the cabin?

In GBA Pro help | Asked By Mark Darley | Sep 19 12
4 Answers

Has anyone ever heard of straw bales being used as insulation in a brick house?

I'm going to build a timber frame using OSB. Then put a red brick skin around this. On the inside of the timber frame I'll line all the outer walls with bales.

In Green building techniques | Asked By Martin Caunce | Sep 24 12
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