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4 Answers

Attic access: What is the best way to maintain an airtight seal?

Once again, I'm a guy building a house--someday. After my seemingly endless perusal of this website, I've concluded that (a) attics can't be drywalled off and forgotten, even though I won't ever want to go up there, and, (b) an oft-sold accessory, the pull-down attic stairs, is a really bad idea for an energy-efficient home. Given these facts, can anyone suggest a simple, airtight detail which will allow attic access and maintain the integrity of the building envelope?

In Green building techniques | Asked By Gordon Taylor | Apr 24 12
2 Answers

I currently have an oil hot water heating system. I wish to get off oil.

What is the most economical and green solution? Wood is not an option.

In General questions | Asked By Jan de Graaf | Apr 23 12
5 Answers

Spray foam for a concrete brick house

Hello,
I plan on spray foaming my house really soon. it's a post-WW2 home with concrete brick as an exterior cladding. I have read the article on the precautions of insulating brick homes, but there is a slight difference.
http://www.greenbuildingadvisor.com/blogs/dept/musings/insulating-old-br...

1. Are concrete bricks generally more resistant than clay bricks to spalling?

In Energy efficiency and durability | Asked By gramps888 . | Apr 16 12
7 Answers

What are my options to replace fiberglass insulation in vaulted ceiling?

The vaulted ceiling is scissor truss construction with a 6/12 ceiling and 9/12 roof pitch. I've been in the attic and have very limited access, but I can see wires running through the insulation, gaps, and no insulation on top of the ridge peak. In order to replace the insulation I figure I will have to remove sections of the drywall for access from below. When I gain access from below I could rake out the fiberglass insulation and then use some type of blowin insulation. What insulation could I have blown into this space with a 6/12 pitch?

Thanks for the advice.

In Energy efficiency and durability | Asked By Brad Dorken | Apr 19 12
10 Answers

What is the correct way to manually calculate air infiltration heat loss?

I am designing my own house and I would like to figure out the Heat Loss & Heat Gain numbers to verify if the subcontrator's calculations are right. I think I've got the formulas for those, but I don't under stand 2 numbers in the equation, if this is the correct equation?

Air Infiltration Heat Loss = Room Volume X Design Temperature Difference X AIR CHANGES PER HOUR X .O18.

My questions are: How are the number of Air Changes per Hour arrived at? and What is the .018?

Thankyou,
Ron Lay

In Mechanicals | Asked By RON LAY | Mar 19 12
5 Answers

Recommendations for Manual J software?

Hi All,

I'm looking into software to perform Manual J calcs, and perhaps also do other simulation/calculations as well. I'm fluent with the PHPP and another software called TrnSys (from a previous job), but I'm looking for something more common in the residential efficiency world.

In Mechanicals | Asked By Cramer Silkworth | Jan 10 12
3 Answers

Sealing Brick Veneer...or not?

I have a modular masonry fireplace. The chimney has a brick veneer with a small gap between the brick and the masonry blocks. I initially had a small leak through the brick and onto the chimney's built-in brick ledge (in the attic) during a rain. This seems to have stopped based on observation during subsequent rains. It has been recommended that I spray the chimney brick with a sealer.

Questions:
1) Do I need to do this? Why did it leak at first and now it doesn't? The mortar wasn't fully cured at the time of the initial leakage---would that make a difference?

In General questions | Asked By john walls | Apr 22 12
3 Answers

Installation of finless windows

I will be buying windows for a new construction. The difference in cost between windows with nailing fins and those without is $1000 for the package. This is significant money and I would like to take advantage of it unless there is a compelling reason not to. If the reason comes down to ease of installation I can deal with that. What are the other benefits of fins over non-fins?

In Green building techniques | Asked By Ben Raterman | Apr 18 12
6 Answers

1.5-inch-thick polyisocyanurate insulation on cinderblock walls

I am working on a cinderblock house (every forth cell is solid) with plaster interior finish applied directly to the cinderblock. We are replacing windows, doors, and siding and the idea is to fur out the cinderblock and place polyiso insulation between the furring strips, then .5 inch OSB over the Furring and insulation, then house wrap/stucco wrap, and stucco part of the house and wood clad other sections of the house.

In General questions | Asked By John Placek | Apr 17 12
2 Answers

Hawaii construction: doors, windows and the elements

I've worked in design & construction for decades now, but am faced with a challenge to design & build a house in a very windy, salty, sunny, termite infested location in Hawaii (and yes, subject to earthquakes, but only 110 mph winds).

In Green products and materials | Asked By d t | Apr 20 12
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