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10 Answers

Bubble wrap window insulation testing

I have a large amount of glass in my 1965 home. I had read a question here that talked about window quilts and that eventually led me to the idea of covering windows with bubble wrap.

Much of my glass including large sliding doors etc are all bare aluminum frames without thermal breaks or insulation. The idea of adding a semi-clear covering that admits light and I can apply over the glass and frame is pretty appealing.

Of course replacing the windows is a huge expense. Some have single pane and others are double pane from 1965.

In General questions | Asked By Mark Renfrow | Feb 9 11
6 Answers

Can I spray closed-cell insulation on inside of brick wall ?

I live in South Louisiana and am remodeling a Ranch Style Brick Home. I have removed the drywall and have 2 x 4 studs, 1/2 " impregnated sheathing, 2 1/4 " dead space then brick and mortar.

If I remove the 1/2" sheathing from the inside (easy to cut out) , this would give me 6 1/4 " space to insulate. Could I spray the closed cell spray foam directly aganist the inside brick wall filling the wall cavity up to edge of 2 x 4 , then finish with new drywall? Would this create any future problems for walls?

In Green products and materials | Asked By Theresa Aguillard | Nov 27 12
3 Answers

Recessed lights/speaker caps

The family that lived in my house previous to mine were music lovers. As a result, they installed two 8" ceiling speakers in every room of the house, including the baths! Now, in addition to the 26 chimneys commonly called recessed lights that penetrate my ceilings, I also have 24 chimneys that produce music while they leak!

In Energy efficiency and durability | Asked By Chris Brown | Nov 29 12
3 Answers

Small unvented soffit area

The front elevation of my home contains a gable roof area that protrudes less than two feet from the main front wall. There is of course a very small and isolated soffit area on each side of the gable in this 2 foot protusion, that is purely for design as it contains no soffit vents. The gable contains a ridge vent (as does the rest of the attic) and a gable vent. The attic area above this gable area is common the the rest of the house attic, which has functioning soffit vents and baffles.

In General questions | Asked By Chris Brown | Nov 29 12
2 Answers

How effective is passive inlet ventilation?

I am the second owner of a house I have been retrofitting for a couple years, primarily for energy efficiency. The attic has been brought up to R65 with blown paper cellulose, the rim joists have been insulated with foam, etc. The insulation/weatherization upgrades have brought our house from approx .38 air changes per hour down to .23ach according to blower door tests. We have installed very efficient bath fans and wonder how effectively a product such as the Panasonic passive inlet vent will work in conjunction with the bath fans.

In General questions | Asked By Christopher Ring | Nov 28 12
2 Answers

Should I vent enclosed soffits on a house with an unvented cathedral ceiling?


In GBA Pro help | Asked By Rick Schneider | Nov 29 12
1 Answer

One or two HRVs?

I recently purchased a ~3000 sq. ft 2 story colonial built circa 2001 in the seacoast New Hampshire area.

It has an unfinished/unconditioned basement. It has a unfinished walk up full height attic, with only the front roof requiring a knee wall.

I plan on converting the attic to conditioned living space. That will add ~5-600 additional sq. ft.

The house has hydronic baseboards. There is no A/C nor HRV ductwork.

In Mechanicals | Asked By Matt Zahorik | Nov 28 12
3 Answers

How to mount a deck ledger on a Larsen truss wall?

We need to mount a 2x8 pressure-treated deck ledger to a conventionally framed wall that has a 8" larsen truss attached to it.

The frame is as such: 2x10 rim joist bearing upon 2x6 mudsill, 5/8" T&G OSB, 8" Larsen truss, 1x4 cross-strap, Tyvek. The deck ledger will be mounted at the same elevation as the rim joist.

The supported length of the deck is not too great, between 5-8'. I would like to attach the ledger on the same plane as th 1x4 strapping and not directly against the OSB.

In General questions | Asked By erik olofsson | Nov 27 12
5 Answers

Can I put foam board insulation on top of one floor and lay another floor on top of it?

I have a enclosed porch that I am trying not to crawl under to put insulation. I also want to make the floor level. So I want to know if I put foam board insulation on top of the old floor and level the new floor, will the new floor keep the cold out?

In GBA Pro help | Asked By Greg Logan | Nov 25 12
7 Answers

Vented Roof Cavity?

For annoying reasons (drawings were wrong, framer didn't catch in time), the roof on an addition we're doing was built lower than it needed to be to line up with the soffits on the existing house. We decided the easiest solution would be to just build up a 6" frame on top of the sheathed roofing so that the new higher roof would line up correctly. The original roof is still in place and has 6" of open cell foam on the underside. The result is that we have a roughly 6" dead space between the foamed, sheathed and papered original roof and the new sheathing. We're putting a metal roof on.

In Energy efficiency and durability | Asked By Mike Ball | Nov 28 12
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