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6 Answers

Gravel under garage floor?

I've seen that gravel is generally recommended under basement floors, but haven't yet been able to locate an article discussing garage floors. In zone 5 SW MI. Planning to use 2" reclaimed XPS under garage floor which is on high ground with sandy soil. Excavator and builder say that floor should be sand, XPS, poly then concrete. If gravel should be above sand, how much? Thanks!

In Energy efficiency and durability | Asked By Dave Owens | Apr 19 16
26 Answers

Heating and hot water

We're empty nesters building a new home. I'd like to bounce some ideas off of you and looking for suggestions.
Current home, 2000ft2 20yr tract home. gas forced air heat. SE exposure & we let the sun in. Current usage: 3494kwh/yr electric, 9317 kwh/yr gas. I think we're pretty frugal with our energy consumption, we keep the stat set low during the day, and essentially off at night.
New home will be in central CO, plenty of sun. 6939 htg deg days (about the same as current location). Average low in Jan is 12.4F. AC is not needed.

In Mechanicals | Asked By brad haack | Apr 6 16
3 Answers

Is it a good idea to use foil-faced rock wool under the basement slab?

I will be building a new house in climate zone 5. I'm doing my best to achieve the R10-20-40-60 insulation level goal. I've been able to find some discount rock wool board that I would like to use below the concrete slab in the basement. Specifically 1" thick Thermafiber Firespan 90. This has a 8.0pcf density which would be good for sub slab, however it also has a foil faced vapor retarder. I would like to stack 2 layers of the product to achieve an R8.4 value (close enough to the R10 goal).

The basement slab construction is as follows (from top to bottom):
4" concrete with wire mesh

In Energy efficiency and durability | Asked By Adam Peterson | Apr 19 16
98 Answers

Ideas for this floorplan

Hi all! I'm new to the site here and was hoping to gather some feedback, or to change my plan altogether.

I'd like to build a ranch on a basement with plenty of southern glazing. I found the attached plan as a starting point but I'm afraid that if I move forward, I'll just spend a bunch of money creating blueprints only to find that I needed to change something after the fact.

In Plans Review | Asked By Drew Baden | Mar 9 16
7 Answers

Is there an under-sink recirc pump model that has an ECM motor and can be operated on demand?

I'm looking for a recirc pump model that has an ECM motor and can be installed in a house without a dedicated return line and can be operated on demand. The best option I've found so far is the Bell & Gossett ecocirc wireless (http://bellgossett.com/pumps-circulators/circulator-pumps/potable-water-...), but I don't really need/want the wireless part or the batteries. Hard wired is fine/preferable.

In Green products and materials | Asked By Chris Stratton | Apr 7 16
1 Answer

What form or shape of a pavilion design will be suitable for Chennai?

What form or shape of a pavilion design will be suitable for Chennai? Can have it with examples?

Which structure of a pavilion will absorb low heat in Chennai?

In General questions | Asked By Mani Priya | Apr 19 16
4 Answers

Unvented cathedral ceiling condensation issues

Hi there,

I received a call form one of my Architect clients. His friend recently re-built his roof and now has major condensation issues; so I went to take a look. Here is the constructed assembly as best as I can figure, pictures attached.
Inside to Outside
1. Heavy timbre with wood cladding in between
2. 6mm poly that wasn't removed attached to the heavy timbre's with acoustical sealant and staples
3. From here the old roof was removed from the outside. Between the heavy timbre's polyiso was tuck taped to the timbres to give the foamer something to spray against.

In GBA Pro help | Asked By Kristopher McMenamon | Apr 18 16
4 Answers

Can I get the name of an appraiser in the New Orleans area who is appraises homes with "green" technologies?

I am getting ready to sell my home. I live in Mandeville, Louisiana, right outside of New Orleans. I want to get my home appraised, and would like to have someone who knows about green technologies. When I built my cottage six and a half years ago, I used as many green technologies as I could afford - foam insulation, a white metal roof, Hardy board, trex on the porch and deck, etc.

Thanks for any information that you can provide!


Vera Clay

In GBA Pro help | Asked By Vera Clay | Apr 17 16
1 Answer

Can I insulate inside cavities after drywall is up?

I live in a colder climate in a home completed in the 70's. The former owner put drywall up in the basement without insulating in some spots causing cold infiltration. In other areas the wall cavities are only partially filled with fiberglass batt insulation - again leaving cold gaps.

Is there anything I can do to better insulate these areas without having to remove the drywall or the outside cladding on my basement walls?

In GBA Pro help | Asked By Carl Dillon | Apr 18 16
8 Answers

Low/No-VOC PVA glue and Caulk

Hi there,

Just want to be sure I'm not missing anything ---from the reading I've done, it seems that most PVA woodworking glues are fairly nontoxic...We have specified no or low-VOC products for our remodel, but our contractor is not an expert in this area. They want to use Titebond II. It seems like a safe choice. Does anyone agree or have a better suggestion for a carpenter's (wood) glue -- aiming to have a minimal impact on indoor air quality--very limited off gassing.

In GBA Pro help | Asked By Mindy Munger | Aug 14 14
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