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1 Answer

Insulating a crawlspace with brick foundation walls

I have read a lot on this web site about the proper way to insulate a crawlspace; most of the responses seem clear for houses with cold climates or hot climates, but what about mixed climates (such as Virginia). We are very humid in the summer and cold/ freezing in the winter.

In Energy efficiency and durability | Asked By chris harrison | Sep 29 13
8 Answers

Best choice for windows in passive solar house?

We have a passive solar house in northern New Mexico and we need to replace our 19 4'x6' clerestory windows. We seem to have the choice between clear glass double pane windows, or Low E windows with an SHGC of .29 and a U factor of .31. I know that a higher SHGC window would be ideal, but that doesn't appear to be an option in our price range.
So, is it better to sacrifice heat gain for better insulation, or sacrifice insulation for better heat gain? Summer overheating is not an issue -- I'm worried about winter heating. Thanks for any advice!

In Energy efficiency and durability | Asked By Lynn McDonald | Sep 28 13
9 Answers

Air Tight Garage Door?

I have a unique set of requirements for a garage I'm building. I've been unable to find anything online in terms of 7' x 7' air tight garage door.

1. Because of plumbing in the garage, I have to heat it all winter in an especially high altitude (cold) location in zone 7b.

2. The insulation is R-40 walls, R60 attic, R-20 around the foundation, with FPSF detailing.

3. I don't need to open the garage door more than about 10 times per year.

In Green building techniques | Asked By Kevin Dickson, MSME | Aug 30 13
4 Answers

Connecting the output of solar hot water panels and a GSHP desuperheater to preheat domestic hot water?

I am installing both Enerworks solar thermal (hot water panels) and a Bosch GSHP (water to air) with desuperheater and am looking for advice on the best way to connect the two systems together to pre-heat/heat my domestic hot water.

Vendors of GSHP systems know how to plumb their de-superheater output to pre-heat DHW, as do the solar hot water panel vendors, but it seems to be an opinion rich environment when it comes to integrating both systems.

In Mechanicals | Asked By Lee Reed | Jan 22 13
2 Answers

3M All Weather Flashing Tape VS. Grace Vycor when used in flashing on plywood

Does anyone have experience with comparing these flashing tapes: 3M All Weather Flashing Tape compared to Grace Vycor Tape?

In General questions | Asked By Eric Mikkelsen | Sep 28 13
1 Answer

Gaps Suggestions for Cedar Rainscreen Application

Our house is in the PNW and we will be siding it with 2 layers of 30 min felt and 1X4 cedar horizontally connected to vertical 1X1 ripped Trex Decking furring strips. We are adding fiberglass screening to the top and bottom.

Because of the wasp and other creatures and their desire to inhabit warm dark spaces, we were wondering if anyone had a good rule of thumb for gaps between the boards.

Our plan is for a 1/8th inch gap. Should we simply cover the entire surface behind the boards and atop the battens in the screen material, or will that have its own problems?

In Green building techniques | Asked By Buzz Remde | Sep 28 13
2 Answers

Will we need a sealed combustion boiler with bathroom fan ventilation?

We are building a "fairly tight" house in Central NH. It will be 2x4 construction with BIBs insulation and 2 " of polyiso foam on the exterior. We were planning on using a natural draft propane boiler for our heat, but we are now wondering if the negative pressure will cause problems. We were not planning on installing an HRV, but using bathroom fans on timers for ventilation. We are doing all the designing and general contracting for the house ourselves, and my husband is a plumber, so he will be doing the heating system (forced hot water).

In Mechanicals | Asked By Kim Krotz | Sep 28 13
1 Answer

Preferred subfloor material and adhesive for minimum off-gassing?

Does some subfloor and adhesive rate better than others for minimum off-gassing? Regular OSB is the least expensive, but are some brands better than others? and the same with subfloor adhesive; is there a healthier brand for indoor air quality or is it all about the same?

In General questions | Asked By Eric Mikkelsen | Sep 28 13
2 Answers

Slab on grade polyethylene placed below or above foam board insulation

Is there any issue placing the plastic sheeting under the foam board insulation to protect it from punctures caused by rebar placement and tears during the pour?

In General questions | Asked By bob holodinsky | Sep 28 13
6 Answers

To vault or not to vault the great room?

My husband and I are getting ready to have our retirement house built in northwestern Virginia (zone 4A). We're going for a "Pretty Good House" in terms of insulation, windows, etc... It seems that most floor plans with a master bedroom on the main level have a "great room" (approx 18x20) with a 2-story vaulted ceiling. Guest rooms are upstairs, which is perfect for us. We can orient the exterior wall of the great room to face south for passive solar gain in the winter.

In Energy efficiency and durability | Asked By Cindy Steinkamp | Sep 21 13
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