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4 Answers
Thermal Eather Storage

Creating one of the most comfortable and economical heating systems available, SmartRooms Earth Thermal Storage System is installed in soil or sand under a concrete slab building foundation. (Sometimes called slab heating.) The result is that the ground underneath becomes an efficient, large mass of stored thermal energy. It's the same principle as the earth's core.

Their entire "energy saving" seems to depend on time of day off peak electrical rates as far as I can tell.
http://www.thermaray.com/solutions/earth.html

Comments?

In Energy efficiency and durability | Asked By Ted Ross | Apr 21 10
13 Answers
Durable, yet breathable roofing underlayment.

I am building a home with a conditioned attic. I will be spraying 11-12 inches of open cell foam underneath the roof sheathing. I need to allow the sheathing to breathe to the exterior, for it will not breathe to the interior with the 12 inches of foam. Thus, I was wondering if anyone was aware of a roof underlayment (other than building paper) that is breathable, durable, and that has a high exposure rate.

In Energy efficiency and durability | Asked By JAMES MOYER | Jul 22 09
2 Answers
Liquid air barrier for basements?

I live in Maryland and would like to improve the thermal performance of my basement. It has about 6 feet below grade and 3 feet above grade with slider windows. I currently have wood paneling in front of the brick masonry walls with one inch separation. Since the paneling includes a partition wall and looks nice, I would like to keep it. But I am thinking of shifting it forwards to allow for insulation between it and the brick wall. However, I doubt the paneling is effective as an air barrier.

In General questions | Asked By Richard | Apr 19 10
1 Answer
Venting a radiant barrier airgap in roof?

I'm designing an R30 roof. The top layer is 7/16 radiant barrier OSB, with the foil faced down. These will rest on 1x sleepers, which are attached to the rafters through a 2" layer of foil faced polyurethane foam board. Cellulose fill between the 2x6 rafters. Roof is 4:12 pitch in Southern California - tops out at 90 degrees F.

In Green building techniques | Asked By Paul Prunty | Apr 20 10
1 Answer
In new construction would the blown in /with glue cellulose insulation be the best to elliminate setteling and air gaps in wal

I am looking for the best type of insulation to use in a new house. The house will have brick exterior, quality windows and doors and 2x6 wood wall studs. The interior will be drywall. The roof will be composition shingles over wood decking. I wish to have a house that is comfortable with minimal cost for heating and cooling, as well as one that will breath and allow moisture to pass to the outside with out damaging the materials. The house will be located in North East Texas so high summer temperatures can be expected as well as high winds.

In Energy efficiency and durability | Asked By J. Rob Dove | Apr 20 10
2 Answers
Steel or wood studs for spray foam basement

My client wants 4" of closed cell spray foam installed in stud cavities in his basement. Location - Toronto, Canada.

What studs should be used to frame foundation walls with - steel or wood?

The debate is that 2x4 is taking 1.1/2" of space that could have been filled with foam if steel studs were used instead since they are only about 1/16" thick.

Your input will much appreciated.

In Energy efficiency and durability | Asked By Andy Sosna | Apr 18 10
18 Answers
Cellulose Netting and Airtight Drywall

I was at a job site today where the cellulose contractor was finishing up and the drywall contractor was unloading his materials. The double framed exterior walls had been netted and denspacked and were ready for hanging drywall. Netting had been installed over the studs and fastened to the sides with an upholsters staple gun. The plan was to go with the airtight drywall approach and latex vapor retarder primer, and sealing the drywall to top and bottom plates as well as inside corners and window perimeters.

In Green building techniques | Asked By Jon Wyman | Apr 12 10
7 Answers
Moisture on underside of roof deck

So a client of mine removed existing batt insulation from a rafter bay that happen to be touching the underside of the roof deck (no air space) and there was condensation on the rood deck. However when he removed the insulation from the remaining rafter bays there was no condensation or discoloration of the wood deck. And now that the insulation has been removed, the spot that was wet has dried out.

So was the condensation just a cause of the natural vapor transmission through the materials and because there was no air movement, the moisture had a chance to condense on the surface?

In General questions | Asked By Joshua Lloyd | Apr 8 10
14 Answers
Is it true that a home loses 10% of heat through conduction, 25% through convection and 65% through radiation?

I have seen an ad for a product that states these numbers. Is this a proven building science fact? If so why wrap homes in house wrap that is not foil based? Wrap it provide a 1" gap and side over the wall. It would seem more efficient than super insulated walls without the foil.

In General questions | Asked By Bruce Chyka | Apr 7 10
7 Answers
What have you heard about the EPA renovation, repair & painting rule going into effect this month?

Does this mean that if I own a house or I am a contractor renovating a home built before 1978 I must be certified to do the work or I will be fined huge amounts of money? Do you know anyone who is certified? I know that it is important to do the work properly but it seems like a nightmare of red tape. Just more government in our lives where people are already struggling to survive.

In General questions | Asked By Maria Hars | Apr 16 10
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