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7 Answers

1” sleepers with 3/4” EPS on a concrete basement floor?

I have a home in Zone 5 with a walk out basement. The basement floor is concrete and the current concrete to bottom of ceiling joist measures at 7’-4”. I would like to float an engineered floor, but ceiling height is an issue. We plan on finishing the walls and ceilings so I’d like to keep the floor as thin as possible. Would 3/4” EPS be too thin? I have read that if you go too thin it will never dry out and that 1” is preferred, but we would like to do 1” sleeper with 3/4” EPS then 1/2” Plywood then 1/2” engineered floor. So 2” thick, but even that is pushing it.

In Green building techniques | Asked By Alissa | Dec 9 15
6 Answers

Will an uncovered OSB roof be okay for the winter?

I'm building a house in Northern Michigan currently that I was unable to roof before the snow came down. That was in December, so it's been sitting for a month. There hasn't been that much snow melt here and temperatures have mostly been below freezing. The roof has ice below so I can't really scrape everything off to shingle it right now. Is there any danger of waiting until the major thaw and then scraping it all clean then? Do I risk wetting the OSB too much? Mold? Any other dangers? Also, how long should I let the wood dry before I attempt to roof it?

Thanks ahead of time.

In General questions | Asked By Jeremy DuCheny | Feb 14 16
34 Answers

Roxul board used in basement as insulation against concrete wall?

I just watched a mike Holmes episode. He was building out a basement for bar, home theater, gym, etc. against all the walls he used roxul board as an insulation barrier then the walls were framed. I've read where Martin Holliday advised against this practice. Who's right? It makes more sense to use foam or foam board as it won't hold water. Thanks for any clarification on this topic.

In GBA Pro help | Asked By tim gabriel | Mar 5 15
3 Answers

Rigid foam on the roof

We are remodeling the exterior of our 115 year old farm house this year and felt it would be a great time to tighten the envelope and add rigid foam to the exterior. However, our contractor has some concerns about the extra weight of five inches of foam over the roof. Is this a valid concern? It's an old house. The frame of the roof consists of actual 2x4s placed 24 inches apart. We nailed 2x12s to the 2x4s eight years ago to provide a cavity to put blown in cellulose.

Thanks for the advice, Ryan

In Green building techniques | Asked By Ryan Knight | Feb 11 16
0 Answers

I'm looking for an energy expert in the Richmond, Va, area

Hi Everyone,
I plan on building a super insulated, sealed crawl, air tight home in the Richmond Va area. I am looking for a local energy expert to help me design my mechanical sys. I would like to use a mini split heat pump with some type of mechanical ventilation. Does anybody here know of a Richmond area person or company that could help me with design and consultation?

Thank you,
Steve Stemper

In Mechanicals | Asked By Steve Stemper | Feb 14 16
5 Answers

Sealing and insulating hatchway to vented attic

My attic is now insulated with 18" of cellulose. The builder left a hatchway from a closet in case we need to access the attic -- it will not be used for storage, just for access if something goes wrong. The builder suggested using a piece of plywood with a couple sheets of foam insulation on top to cover the hatchway.

Does that make sense? How can it be air sealed so that it is not a chimney sucking up warm air? Would weather stripping suffice?

In Green building techniques | Asked By David Martin | Feb 12 16
1 Answer

Where to find Energy Star floor plans?

I am looking to have a home built on my lot in the near future, and am interested in getting an energy star home. Do I need to specifically look for house plans that are designed to meet the energy star standard? Or can any house plan work? If I need to get special plans, where can I find these? I have not had much luck searching on google, and the few I have found do not specify which version of the standard they adhere to!

In General questions | Asked By Billy Clontz | Feb 14 16
8 Answers

Off-label use for open cell Iso foam?

GC is proposing to use Iso open cell foam as bulk fill in lieu of compacted gravel / sand fill over existing residential interior concrete slab on grade, to provide a base for a new interior concrete slab. Requirement is to bring a 15' X 19' X 12" deep "ashtray" up to level with surrounding floors and finish with tile to match adjacent. Application is strictly structural; insulation value is not a benefit. Existing recessed slab is 4" above base flood elevation including freeboard, existing plumbing drain pipes are below the existing slab.

In Green products and materials | Asked By Leslie Divoll | Feb 12 16
10 Answers

Raised-heel trusses can be annoying

We installed raised-heel trusses with bottom chord overhangs on our house. The top of the top chord is 20" above our top plate. According to the 2012 International Residential Code for seismic zones or zones designated for winds of 100 mph, raised heel trusses more than 15.25" have to be blocked and braced.

In Green building techniques | Asked By Jimmy Nguyen | Feb 6 16
39 Answers

Will minisplits work in all floor plans?

I'm researching the details of building a new house in central KY, zone 4a. This will be the house that lasts for the rest of our lives (hopefully 50+ more years). I had assumed that GSHP were the "no-brainer" HVAC choice, but from the looks of things, it isn't that simple. I've been reading some amazing things about the potential of mini split systems.

In General questions | Asked By Clay Whitenack | Jul 20 15
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