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2 Answers

Adding foam insulation to the roof on a manufactued home

I have a neighbor here in Vermont who needs a new roof on her 70's doublewide manufactured home. The roof currently has asphalt shingles on OSB. The roof is vented. I thought this might be the perfect opportunity to add some foam insulation on top of the existing sheathing. I can do metal over strapping on top of the insulation or asphalt over another layer of OSB. Which will perform better? Is the payback worth the cost? Currently heating with propane. The roof only has moderate slope. What do I do with the existing vents? Any suggestions are appreciated.

In Energy efficiency and durability | Asked By William Brooks | Nov 16 15
2 Answers

3-story apartment foundations?

Tips for this? Requirements?

In Mechanicals | Asked By Jose Tribaco | Nov 15 15
2 Answers

True cost of flex duct?

Hey Folks,

I've read many of the reports and advice about flex duct, friction loss, and reduced airflow. What I have not found is how this translates into actual dollars. Can anyone point me in the direction of such a study? Of two systems with one having properly installed rigid duct with short flex runs and the other having rigid trunk and all branch runs in flex with the typical bends, sags, etc. What will be the actual financial operating difference in the two?


In Mechanicals | Asked By C. Maglio | Nov 15 15
0 Answers

Anyone have experience with Monessen gas fireplaces?

We are interested in this brand and wonder what user feedback is. http://www.monessenhearth.com/Products/Covington-Direct-Vent-Gas-Firepla...

In Mechanicals | Asked By Joe Suhrada | Nov 15 15
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 7 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 13 15
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