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5 Answers

Hi,
I am building a new home and looking for the best way to insulate. I think the spray foam is the best but also the most expensive.

My builder is researching a new foundation water proof system called Enviro-Dri. Does anyone have any experience with that, or do you have another method you like better?

Thanks.

Asked By lisa lockwood | May 20 13
3 Answers

I previously had asked about the potential of constructing a rudimentary geothermal basement by purposefully NOT insulating the masonry walls of a basement. Martin pointed out that the ground temps in NY/NJ/CT in winter at the surface are freezing and not until something like 48 inches are they above freezing, say around 40 to 45 degrees? Thus making it clear the walls should be insulated. But what about the the floor slab? Assuming a depth of say 9 feet at the slab's underside, would this not be a constant 55 degrees or so? Thus be warming in winter and cooling in summer?

Asked By Sal Lombardo | May 20 13
4 Answers

I've purchased a city lot in Tucson, AZ and plan to build a tight, well insulated home on a concrete slab-on-grade within the next few years. It's a hot, dry climate with 1578 HDD, 3017 CDD, so obviously keeping the house cool is the big concern.

Asked By Michael McNulty | May 20 13
11 Answers

I am an architect in Atlanta, GA (climate zone 3) mostly designing modern/contemporary homes that typically have flat roofs. There seems to be a lot of conflicting information and opinions out there as to the best way to insulate these types of roofs. Typical construction would be 12" deep ceiling/roof I-joists or 2x4 open-web trusses with flat OSB decking above. The most common potential options (all unvented scenarios)are:

Asked By Scott West | May 11 13
8 Answers

I can't verify, but I read sometime recently that there's less embodied energy in buying a CD than in storing it on-line. Which got me to thinking about these monster servers that must be sprouting like mushrooms. I have a vision of us all living in lovely net zero homes, served by our own individual off-site servers consuming a Fukushima's worth of juice.

No real question. Just wanted to share my cheerful thought before the weekend.

Asked By Dan Kolbert | May 17 13
27 Answers

I am building an Energy Star certified home with fiberglass, triple glazed, low e casement windows and slider/patio doors in Connecticut. I prefer using a Canadian company because of their expertise with fiberglass, triple glazed windows and sliders. I must have window specifications for the Energy Star certification, preferably NFRC ratings or at least independent U, SHGC and VT value ratings. Window ratings do not seem to be diificult to acquire but slider/patio door ratings can not be provided by some manufactures for fiberglass triple glazed sliders and French doors.

Asked By JOSEPH POLAND | Jan 15 13
7 Answers

I have a passive solar off-grid home that works extremely well with a 2 in. concrete slab that is finished with decorative concrete stain/paint. However, the slab and stain/sealer are completely defective and very likely have to be replaced, but one party is proposing a concrete overlay product be put atop the existing slab. The overlay product (ArtCrete Deck Coat, I think it is) consists of two parts--1) Portland cement, aggregate, and a stain, and 2) a modified acrylic latex resin.

Asked By K Tot | May 13 13
154 Answers

Does anyone have experience with Serious Windows or Canadian fiberglass windows? I'm having a difficult time finding high SHGC windows (with a U-value less than or equal to 0.30) for my passive solar home that are affordable. Looks like the fiberglass windows can give me the performance I'm looking for, but I can't find any local installations to inspect the quality of manufacture.

Asked By Claire Anderson | Oct 1 09
3 Answers

I want to blow cellulose in my attic, but it is impossible to get a very good r-value in the tight space where the roof slopes down to the soffit.

Asked By Nick Welch | May 9 13
6 Answers

I'm building a house in zone 6a. Local codes require 2" of rigid foam on the outside of the foundation wall, so that's what we did. We plan to insulate under the basement slab (1.5 or 2 inches of rigid). We also plan to install radiant heat in the basement slab. Should I insulate around the edges of the basement slab to prevent continuous thermal bridging and heat loss from the heated slab into the foundation wall and eventually down to the footing and into the ground?

Asked By Mike McKernan | May 8 13
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