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15 Answers

Wood floor underlayment over radiant heated floor

Hi,

I am building a 2 story house wood frame house(with basement) that is heated with radiant hot water system installed in the floor.

The joists have been blown in with loose fill cellulose (for both sound and to keep the heat up) and a plywood floor is on top of the joists. R5 foam board is installed on top of the plywood and the PEX tubes are installed to the foam board. They will be pouring a self leveling concrete on top of the PEX and then gluing down engineered wood floors.

Asked By Howard Klein | Mar 5 14
4 Answers

Double wall exterior sheathing

I am designing a near zero energy home in climate zone 5 and working out the details for a double wall system.

There is a lot of talk about what kind of sheathing to use or not use due to the fact that the sheathing will be very cold. As I understand what I have read so far, it is recommended NOT to use OSB or foam but OK to use DensShield Gold, structural fiber board or plywood in Zone 5.

Asked By Terry Herschberger | Mar 2 15
6 Answers

Running PEX in-floor in addition to baseboard

I'm building a new wood frame home with hot water baseboard heating in climate zone 6. The bathroom will have tile floors and I was thinking of using some electric resistance heat under the tile along with a baseboard hot water radiator in the bathroom. These electric systems are not inexpensive to install or operate so I am now considering simply running loops of Pex (the supply line to the bathroom radiator) between the joists to keep the tiles warm before the water in the line gets to the baseboard radiator.

Asked By George LaLonde | Mar 2 15
3 Answers

Basement finish floor, slab on grade

With the help of this site I insulated and framed my basement (90 year old house, 8-9" concrete walls). I did 2 inches of XPS (EPS in hindsight would have been greener but I had a deal on some XPS), 2x framing with Roxul R-15 in between 2x. Rock is next and then floors.

Asked By Sean Cotter | Mar 1 15
7 Answers

Buying a house and want to make it super efficient. I have some concerns about the attic. Can you help?

I am about to close on a house that was built in 1972. It is in Longview, Texas. It is 2100 sq. ft. The garage was made into living space at an unknown date. Has a 3.5 ton central air unit and electric furnace for heat (inspector said that is too small and likely was in place before the garage was converted). Flex type ducting in the attic. My goal is to eventually do the entire place from top to bottom, as I can afford it, and make it cheap to heat and cool. I have several plans in mind. Insulation of the attic I think will be my first step.

Asked By Sam Vail | Feb 26 15
5 Answers

What is a correct way of fastening two layers of 2" rigid insulation to the exterior of a 2x6 wall?

I would like to know the correct way to fasten two layers of rigid foam insulation where the total thickness is 4". I am concerned that when hanging this thickness of foam it will be difficult to be sure that the siding application is secure. We will be using HardiePlank horizontal lap siding. This is a form of cement board and heavy on it's own. Any advice.
Thanks

Asked By william dempsey | Feb 26 15
1 Answer

Pier and beam — insulation under floors/house?

I live in a 645 s.f. two-story home on pier and beam. It is not well insulated, not winterized and not the most precise construction. It is about 20 years old and we just purchased it a year ago. My husband and I had plans to work on it to get it better insulated and heated, but he passed away suddenly and now I am trying to think of the things he mentioned we might try.

Asked By Jennifer Shrift | Mar 1 15
2 Answers

Any experience with precast basement walls?

We are planning to build a new home in southeastern Pennsylania. We are very concerned with paying close attention to energy efficiency and using energy efficient products, systems and techniques. One of the proposed contractors has suggested using precast concrete basement walls. His selling points are price, energy efficiency (R-22), built in waterproofing and expediency. He feels there is no comparison when you look at precast versus ICF walls for the basement. Does anyone have experience with these products. Any help will be appreciated.
Thanks,
William

Asked By william dempsey | Mar 1 15
0 Answers

Any new information on using fog machines to pinpoint leaks?

Here's the article.
http://www.greenbuildingadvisor.com/blogs/dept/musings/pinpointing-leaks... several questions were posed with no answers:

Pinpointing Leaks With a Fog Machine
Builders can use theatrical fog to find envelope holes
POSTED ON SEP 18 2009 BY MARTIN HOLLADAY, GBA ADVISOR

Tell-tale fog. Once a theatrical fog machine has clouded the interior of a pressurized building, builders can find envelope leaks by looking outdoors for the escaping fog.

Asked By David A Flannery | Mar 2 15
6 Answers

Converting fiberglass+plastic basement insulation to rigid foam - worth it?

Brick/masonry house with a concrete, finished basement.

The foundation walls are insulated with R11 fiberglass, topped with plastic, and covered with drywall.

I've read vapor barriers below-grade are bad & that wet fiberglass is useless as an insulating material.

Am I overthinking the usefulness in tearing down the drywall in the basement, removing the fiberglass/plastic, and installing rigid foam boards instead?

Asked By Jeff Watson | Feb 28 15
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