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3 Answers

Super slim LED option

I have been looking at replacing my canned lights in the ceiling and considering two options. Unfortunately, cove lights, pendant lights or other options are not popular with my spouse.

In Energy efficiency and durability | Asked By Stan Weinstein | Feb 14 17
5 Answers

What are my options for fastening R-40+ rigid insulation on exposed rafters?

I have 2x10 rafters which I would like to leave exposed. My idea is to put T&G 1x's above the rafters.
On top of the T&G I plan on stacking rigid insulation (R-40 min.)
My question is regarding screwing OSB on top of the rigid foam all the way through to the rafters. Other than using 8", 10", 12" long screws (depending on the type of rigid foam) is there a different way to fasten this together?

In Green building techniques | Asked By Dave-OH | Feb 15 17
8 Answers

Radon fan location: outside via drain tile?

Per the oft cited recommendation, we installed a passive radon pipe in our home during construction. It's piped off the foundation Form-A-Drain and incorporates a top of the house area with electrical circuit and enclosure for the radon fan. We are now at the point where it probably makes sense to install that fan. In fact the fan is here ready to be plumbed in. (I have good reason to believe the passive radon pipe vent works, at least to some degree; certain times of the year you can see frozen water vapor near its output.)

In General questions | Asked By Andrew Bater | Feb 14 17
8 Answers

Insulation contractor recommends open-cell foam for cathedral ceiling

Hi - we are building a new home where the great room section has a cathedral ceiling with dormers on each side. We are planning on spray foaming the underside side of the roof deck, and the insulation contractor is suggesting open cell foam because if the roof ever leaked with closed cell foam, it would go undetected and the roof would rot. We are in climate zone 4A and we used ZIP roof sheathing with shingles applied directly to the ZIP. I would appreciate any input on this.


In Green building techniques | Asked By Brad White | Feb 9 17
6 Answers

Whole house dehumidifier - where to install?

I am currently building a 2 story, 5400 sq ft home in Alabama where humidity is often high. We will install a whole house dehumidifier ("WHD") as part of the HVAC system. We will have 3 HVAC units (2 and 3 ton down, 2 ton up with variable speed air handlers and 2 stage compressors). The installer is proposing to install one WHD (for entire house) on the larger of the downstairs unit which is also the unit that will control the kitchen and great room areas. The master bedroom/bath and another downstairs bedroom/bath will be on the other HVAC unit (no dehumidifier).

In Mechanicals | Asked By Richard Marks | Feb 14 17
1 Answer

Can anyone comment on the performance of the Rehau 4700 Geneo insulated uPVC window and door extrusions?

Can anyone comment on the performance of the Rehau 4700 Geneo insulated uPVC window and door extrusions that are manufactured by Wasco Windows in Wisconsin? They are apparently PassivHaus Certified. Are also triple glazed.

I am planning on building a Certified PassivHaus as well as Net Zero. Also want to use Quadblock ICF for the construction of the envelope.
Part of the design will have a full basement and two doors connecting to the garage. House is located in Ontario , Canada.
Any comments?
Thanks, Andy

In PassivHaus | Asked By Andreas Voura | Feb 15 17
6 Answers

Question on ballpark renovation costs

I know it varies and there are a lot of variables, however.....
Anyone give me a ballpark cost to totally gut my 1 1/2 story , 2 bedroom cape cod style house? Everyroom except the only bathroom, upstairs?
It is 850 square feet, and I am looking to have all drywall replaced, baseboards, trim, ceilings. In the kitchen, when gutted, I might as well have new cabinets, counter, and back splash, with middle grade cabinets, no granite, etc.. currently there are only 7 uppers, and 5 lowers (cabinets).

In General questions | Asked By Dave Mac | Feb 14 17
2 Answers

Open cell vs. closed cell for hot roof in Florida

I just bought a 25 year old home in Jacksonville. 2 Story framed home off grade. We are considering replacing the fiberglass insulation in the attic with spray foam on the underside of the roof sheathing. My goal is to move make the attic more of conditioned space because 1) the air handler and all the A/C ducts are in the attic 2) We're just finishing install a number of recessed cans in second floor ceiling.

In Green products and materials | Asked By Paul Tasillo | Feb 14 17
11 Answers

Questions about furnace air returns

Regarding furnace air returns.
1. Can I get central air installed, have a gas forced air furnace?
2. Would I benefit from fresher air in the home if I had an air exchanger installed?

House built 1920, had coal furnace, converted to gas, had the big octopus in the basement with gravity heat.
Because of that only one duct upstairs in hallway,
None in 2 bedrooms, doors were kept open.
Only one return in living room floor.

Have had forced air furnace for 17 years, live in a electric municipality where electric rates are low, 20-30/month.

In General questions | Asked By Dave Mac | Feb 12 17
10 Answers

Metal standing-seam hot roof

Hi I'm building a new home for our family and wanted to run our roof design by you as my concern is moisture/ condensation. Essentially we have 2x12 members on a low-sloped 2 5/8" over 12 large 3500 square foot roof. I'm planning on insulating with 7" of closed cell (More if recommended) and no vapor barrier because of closed cell not needing it. The roof deck will be covered with Ice and Water HT and then have a standing seam metal roof installed on top of the ice and water. We are located in Massachusetts. One debate is do i use CDX , OSB Standard or advantech.

In GBA Pro help | Asked By Michael Carreiro | Feb 12 17
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