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2 Answers

Insulation retrofit for a 1920s wood-framed home in a mixed climate--Help!

After a lot of research, we continue to go 'round and around' attempting to select the best strategies for envelope improvements for our home. It is a wood framed structure built in the 1920's and we are located in NE Kansas (zone 4 non marine). We live in a rural area that is quite exposed to wind on a regular basis all year, so adding an air barrier is a must.

In Energy efficiency and durability | Asked By Katherine Nichols | Nov 14 15
15 Answers

Tankless gas water heater?

I'm considering switching to gas tankless hot water. I know there are articles here and from Consumer Reports, both a few years old, saying it's not worth it-is that still the case?

What about in my situation? Current atmospheric tank vents to a chimney. Upper portion of chimney is leaking, best solution is to remove it, don't want to rebuild it. It only supports that 22 year old hot water tank.

In Energy efficiency and durability | Asked By Jeremy M | Nov 8 15
3 Answers

Air barrier location in a double stud wall

I'm considering an R-40 double stud wall for Rochester, NY, zone 5, with the following construction:

Shiplap siding,
1x3 furring (rainscreen),
Felt (WRB),
Loadbearing 2x4s or 2x6s filled with cellulose,
Plywood (air barrier),
Gap filled with cellulose,
Non-loadbearing 2x4s filled with cellulose,
[Smart membrane (maybe)],
Paint (Class III vapor retarder)

In Energy efficiency and durability | Asked By John Ranson | Nov 14 15
11 Answers

On an exterior walls sheathed with 1/2" ply, asphalt felt, and ribbed steel exterior siding - Where will condensation form?

I'm in the northern part of climate zone 6B, approx 80 miles south of climate zone 7B.

In Energy efficiency and durability | Asked By Rick Van Handel | Nov 13 15
7 Answers

Can I use aluminium foil on top of my flat concrete house directly facing the sky?

Dear sir,


In Energy efficiency and durability | Asked By Visswanath Reddi | Nov 14 15
2 Answers

Smart Membrain installation details

I am installing CertainTeed's Smart Membrain product over 5.5" of Owens Mineral Wool insulation. The installation instructions are not very clear in the fine details unless I am installing the product as an 'air barrier' in addition to vapor retarder. Located in zone 5.

My insulation is obviously face-less and has no barrier. I have 7/16" OSB and Greenguard 3D Rraindrop House Wrap over that, with Vinyl siding covering the house. The house wrap was taped, but I am certain every staple and siding nail has punctured it in many ways.

In Green products and materials | Asked By Nicholas C | Nov 14 15
2 Answers

Gas Fireplaces

Hi all,

Looking for suggested brands/models on two types of gas fireplaces. We're specifically looking for options with the least toxic materials. We're hoping to not have fumes enter the home from the heating of the fireplace materials. Thank you!

(1) Direct vent gas fully enclosed/sealed fireplace
(2) Direct vent gas fully enclosed/sealed and see-through fireplace

In Green products and materials | Asked By J C | Oct 18 15
4 Answers

Clogged furnace filter air restriction

I remember reading an article not too long that mentioned a test and after 5 years there was not much change in reduced airflow from a clogged filter, but i can't find the article for the life of me, i believe it was on GBA.
Sound familiar to anyone?

In Mechanicals | Asked By Alan B | Nov 12 15
17 Answers

Proper metal roof installation.

We are building a new home in Southeastern Pennsylvania. We are having a Drexel Metal standing seam metal roof installed over plywood sheathing. The attic is unconditioned space with blown in insulation to a value of R-60 or so. Should the metal roofing be installed over strapping. We will have a vented soffit for air circulation.
when discussing with the roofing contractor he is adamant that this is not necessary or appropriate. My thought is that the metal should be separated from the plywood.

In GBA Pro help | Asked By william dempsey | Nov 10 15
4 Answers

Retrofit unvented catherdral ceiling

Hello and thanks in advance for help ...

I am in zone 5 (by your map) Ohio and have a typical cathedral ceiling room addition from the late 70s. T&G knotty pine, followed by 6" fiberglass in 2 x 6 rafters and then the roof plywood ...of course now rotten and was previously replaced!. I am a senior lady trying to get the contractor to do it as correct as possible this time. None of the carpenters seem to know what to do with my situation so I have had to do the research.

In GBA Pro help | Asked By Arlene | Nov 13 15
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