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1 Answer

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
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
32 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
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
15 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
9 Answers

Attic insulation

We are in NE Oklahoma (Zone 3). Looking for advice on insulation for the roof.

Planing on batts in the walls, with 3/4" -1 inch foam on top of sheathing and Hardie siding.

The builder thinks we should foam the roof line.

The house is 24x42 rectangle with a 12/12 pitch roof, 9 ft ceiling both lower floors, with an option of a bonus room in the 3rd floor. Maybe put some mechanicals up there as well.

We will have a total electric central heat and air.

Asked By Quinton Bryant | Sep 28 15
9 Answers

Advice regarding adding insulation to log home with added siding

Hi, we have an unusual situation and I just want to make sure I'm not about to do something stupid! We have a log home that was not well-maintained, so we ended up putting board-and-batten siding over two of the walls to try and arrest the further decay of the logs. We couldn't afford to add insulation at the time. We ended up adding house wrap on top of the logs and then the builders put 2x4's horizontally along the logs (although in some places they had to build out further because of unevenness) and applied the siding.

Asked By Debbie Baskerville | Oct 12 15
5 Answers

How do you assess flash-and-batt installations?

We have begun to see more Builders and Insulators use flash and batt installation and I am not sure how to assess the R-value of the installation and if the installation actually meets the intent of code and programs. Let me make the case… First premise it that RESNET grade one installation is equivalent to meeting the intent of the code as the code only say that insulation must be installed in accordance with manufacture instructions.

Asked By Robby Schwarz | Oct 11 15
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