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1 Answer

Vented & unvented in same roof plane?

Hopefully you can all see this attached glass-house view of my proposed roof.

The open attic at the bottom right of the photo allows plenty of room to super-insulate, same too with the open attic above the 2nd floor ceiling, up in the top left/center of the photo. The sloped roof though poses a problem for super-insulation levels, just not enough depth. What I'd like to minimize is a path of least thermal resistance which would circumvent the high insulation levels in the open attics and favor "Easy" migration through the sloped roof section.

Asked By Alex House | Mar 3 15
2 Answers

Will adding rigid foam insulation to the inside and outside of my d-log house cause mold?

I am planning to add rigid foam insulation to the outside of my old leaky d-log house and adding douglas fir slab siding with chink. My electrician would like for us to fir out the inside to avoid having to router out chases for new wiring. If I add foam insulation (open or cloased cell) to the inside will I risk mold on the logs? The house is located in the upper Arkansas valley in central Colorado, zone 6 I believe.

Asked By Judith Blythe | Mar 3 15
10 Answers

Biggest bang for your buck?

We are about to begin construction of a new home near coastal Connecticut. We are trying to incorporate green approaches where feasible. Three main components are: Insulation; energy source (ie Geothermal); and energy distribution (ie in-floor radiant heat or forced air). Of these three green approaches, how would you rank them in terms of biggest bang for yurt buck, assuming you can't afford all three. Thanks!

Asked By Justin Murphy | Mar 1 15
1 Answer

Floor construction for a finished basement

I have a basement with 7 feet of unfinished clearance, floor to joist. The basement floor and walls are poured with no subslab insulation. The current plan for the floor is to put down a layer of poly, followed by 1 inch of XPS and then 1/2 or 3/4 plywood. The plywood will then be painted or otherwise finished. I'll finish the ceiling using flush-mounted wood or drywall panels between joists. This is all assuming I can get a 2-inch variance on the headroom (i.e., can get away with a 6'10" finished ceiling). Increasing the unfinished headroom is not in the budget.

Asked By Andy Martin | Mar 3 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
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.

Asked By william dempsey | Mar 1 15
0 Answers

Any new information on using fog machines to pinpoint leaks?

Here's the article. several questions were posed with no answers:

Pinpointing Leaks With a Fog Machine
Builders can use theatrical fog to find envelope holes

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
41 Answers

Best way to have a wood fireplace?

We are building a custom house, and are nearing our final planning stages before bids with our architect. We are planning to have a wood fireplace on the ground floor, within the building envelope. When it is burning, it will likely to burned with any glass doors on the fireplace open, for aesthetic reasons. It is only going to be used as a heat source as an occasional backup. What are the best ways to minimize the energy problems of an wood fireplace? It'll probably be a zero-clearance type of fireplace. My husband will not agree to a gas or wood stove, so don't even suggest it!

Asked By Clara Kim | Feb 22 15
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