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0 Answers

Integrated ERV For Multi Floor New ICF Construction

New three story ICF construction / Andersen Series A windows, blown insulated attic in coastal area of Delaware. (No basement)
Geothermal HVAC - Two independent ducted zones
Zone 1: Ground Floor + 1st Floor (total square foot = 2,400)
Zone 2: 2nd (top) Floor (total square foot = 3,000)
Floors are connected by 4 foot stairwell "tower" with landings on each floor.
This is a very tight house and needs ventilation.
Builder forgot to install ERV (in spec) until after home was 99% complete, drywall, trim, paint, etc.

Asked By Daniel Austin | Oct 13 15
38 Answers

How is thermal bridging prevented?

The construction process of our home, in southeast Iowa, was completed in January 2014. The house has fiber cement lap board siding and an interior spray foam insulation. In March of 20014 we noticed moisture accumulating, in a vertical line pattern, on the east elevation of the house.

Asked By S. Schneider | Oct 5 15
16 Answers

Should I go with chimney vent or power-vented water tank for cost savings?

The current chimney vent tank needs replacing, its 8 years old, the anode was never replaced and its rusting internally :(

The current is a natural gas tank, 40gal, chimney vented, its a 6 inch outer diameter, and i have had no back drafting issues of any kind since the furnace was replaced with a high efficiency last year.

Asked By Alan B | Sep 26 15
6 Answers

Venting attic/roof with rigid foam outside roof sheathing?

Hi all,

I'm building a garage in central Maine (Climate Zone 6) with an apartment above the garage (I'm going to insulate the entire building so the garage can be kept at least decently warm in the winter), and I'm trying to build it with energy efficiency in mind while still not breaking the bank.

Asked By Chris Conti | Oct 13 15
4 Answers

Geothermal Hyperloop

I've read about geothermal on this site and understand the downsides of the incredibly high installation costs. However, I just recently came across some info on hyperloops - which are supposed to take up much less space than conventional horizontal closed loop systems. Has anyone had any experience with one of these systems? Do they offer any significant break in terms of lower install costs? Are they more fragile or any less dependable or efficient? Here's a video I found that describes what it is:


Asked By Brian W | Oct 13 15
15 Answers

Roof construction for low-slope roof


Asked By Kevin Hoene | Sep 21 15
1 Answer

Can I put rigid insulation under patio pavers, and should I have a permeable system right against the house?

I am considering replacing the patio outside my walk out basement of my 1959 house in northeast Ohio (zone 5). I would like to put rigid insulation under the new patio to help keep the uninsulated floor slab inside the house a little warmer, similar to a frost protected foundation. In a perfect world I would also like to have the new patio be permeable to minimize rain water runoff. However I ran across a publication from the state of Minnesota that recommends a minimum distance between a permeable pavement installation and a building foundation. So I have several questions:

Asked By Hallie Bowie | Oct 13 15
1 Answer

Attached garage wall detail 2x6 vs 2x4

Building a house next Spring in Northern IL (climate zone 5). We are using 2x6 wall construction and hoping to do 2" of XPS on exterior.

We got our plans back and they show 2x6's on the perimeter for the house and attached garage, 2x4's interior.

The one wall I was wondering about was the wall between the attached garage and the house. The plan shows this wall as a 2x4.

Is there any reason this wall shouldn't be 2x6?

Do I insulate this wall as I would an exterior wall with 2" of XPS on the garage side?

Asked By Adam Peterson | Oct 13 15
1 Answer

Should we install a vapor barrier or no?

Our house was build in 1958 and a recent termite inspection led to a recommendation that we have a vapor barrier installed in our crawl space. We have never had one before (living in the house for 20 years) and it never seemed to be a problem. Do we need one?

Asked By Carol Hepler | Oct 13 15
2 Answers

Post-blow snow woe (snow loading and depth after deep energy retrofit)

This post asks two questions about snow after insulating , (A) changes in loading and (B) changes in the snow line and how to flash for it.


Asked By Mark Baker | Oct 13 15
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