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8 Answers

HVAC supply registers in a mostly heat dedicated system.

I have one other question to pose in regard to the HVAC system which is now being installed in the house which is under renovation right now. The house is a side split with each level five to six steps up from the next making it difficult to run ducts. The system proposed is a hydro forced air system with two air handlers split into two zones each. One unit would be in the attic which will be part of the conditioned space and one in the basement. the unit in the basement was supposed to cover the finished basement and the first floor above.

In Energy efficiency and durability | Asked By Eric Schroeder | Dec 10 10
14 Answers

Another vocabulary dispute

After reading Joe Lstiburek's recent article on cellulose, I felt the need to champion the cause of usage and spelling by pointing out that a contractor can be instructed to dense-pack cellulose, but the resulting insulation is "dense-packed cellulose."

"Packed" is a past participle. I urge my fellow writers not to drop the "-ed," lest we fall into Clinton-speak -- you know, the old faux-bubba routine in which he dropped his g's: "I'm glad to see your smilin' faces today."

In General questions | Asked By Martin Holladay | Dec 15 10
14 Answers

A new roof was put on and I've been sick ever since

We had a new roof put on our house and within 24 hrs I started getting sick. My nervous system is whacked out, can't sleep, intense headaches etc.

I've been staying at my daughters house to get away from the chemicals. My husband and son are still staying in the house and don't seem to be bothered by it. We've been using an ozone machine and filled numerous boxes with charcoal and baking soda throughout the house.

In General questions | Asked By karen glassburn | Dec 9 10
26 Answers

.13 ACH home performance test results...is that too tight for spot ventilation, kitchen fan and electric clothes dryer?

My new house was tested at 50 pascals and my reading was .13 ACH.

The auditor and I also played with the spot ventialtion fans, and his manometer, and we were able to reach -46 pascals with all house fans on and the electric clothes dryer on.

In Energy efficiency and durability | Asked By Frank O | Nov 8 10
18 Answers

Shallow Frost-Protected Foundation questions

Can a Thermomass (http://www.thermomass.com/overview/overview.htm) foundation be used in a Shallow Frost-Protected Foundation in a cold climate? My concern is whether the break in insulation caused by the outside concrete wythe separating the horizontal wing insulation and the vertical insulation in the wall is a problem.

In General questions | Asked By John Hess | Dec 12 10
22 Answers

We are considering the following insulation strategy for a second story addition; does this cause any potential problems?

We are looking at the following wall insulation profile for a second story addition, considering cost, R-value and air sealing. The walls will be constructed with 2x6 framing. Starting from the interior: 1/2 gyp. board, 2" dense pack cellulose, 3.5" closed cell spray foam, 1/2" plywood sheathing, vapor barrier, 1" XPS foam board, cedar shingles.

For the ceilings we are considering 15” of blow-in cellulose.

In Energy efficiency and durability | Asked By David Adams | Dec 11 10
31 Answers

Another wall-plan-question thread

Situation: Fairbanks, Alaska, heating degree days of 14,000. Building a two-story addition onto an existing house, built in ‘80.

Walls will be double-stud, filled w/ dense packed cellulose, 10” to 12” wide. Exterior siding will be T-111, as the boss wants to match the T-111 on the old house. My old walls have a 6 mil poly VB, 13” of ‘glass, then T-111.

Now for the questions:

In Energy efficiency and durability | Asked By John Klingel | Dec 12 10
8 Answers

MD Open Cell in Vaulted Ceiling

I am building the following:

1.5 story house with Vaulted Ceilings and Unvented Attic
2x8 rafters
Richmond VA (Climate Zone 4, 3900HDD)

I am leaning toward MD Icynene (2 pcf) in the rafters, for the following reasons

7.5" at R5.2 per in = R39
Prefer water-based blowing agent (vs. ccspf)
MD/Icynene appears more forgiving in terms of identifying leaks, making later structural repairs (e.g., re-roof sheathing replacement)

In Green building techniques | Asked By Jon Rasich | Dec 14 10
2 Answers

Insulating the floor of a house on piers

Here in south Louisiana & Mississippi we have a lot of homes that are raised on piers, typically 1-3 ft. It would be nice to insulate the floor from underneath, but there seems to be no good way of doing it.

In Energy efficiency and durability | Asked By roger steinbrink | Dec 10 10
7 Answers

Painting Fiber Cement Siding

I'm currently replacing my old cedar siding with CertanTeed fiber cement lap siding. In the process I am replacing the R-11 insulation with an inch of spray foam followed by R-15 Batt. I will then add furring strips to the studs to add depth to make up for the increased thickness of the insulation since I have 2 x 4 walls.

In General questions | Asked By Chris Chatwood | Oct 11 10
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