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3 Answers

Media recognizes USGBC for greenwashing

The cover story today (with two complete inside pages!) for USA Today is a scathing attack on the USGBC and LEED for certifying all-glass buildings and even an over-the-top Las Vegas Casino. The article is chock-full of information which is going to be hard to ignore, I think.

In General questions | Asked By JoeW N GA Zone 3A | Oct 24 12
10 Answers

Insulating a flat roof: ventilated or unventilated?

I have a (very sligthly sloped) flat roof deck held up by 2x8's to which the ceiling for the upstairs room is attached. Therefore, the space between the ceiling and the roof deck is about 7 inches - much like a cathedral ceiling, except that it's basically flat.

In each 16" wide channel there is a pitiful layer of R13 fiberglass batt attached to vapor barrier paper laid against the ceiling, with cold air blowing continuously over and arround it from openings at either end ("vents").

In Energy efficiency and durability | Asked By H Hummel | Dec 12 11
4 Answers

Do you carry on a discussion about remodeling with energy savings, retrofitting existing residential buildings?

Do you carry on a discussion about remodeling with energy savings, retrofitting existing residential buildings? The new stuff is great but we seem to have to make significant compromises for existing properties.

In my residential construction business, homes can have 20-25% of each window in trouble. Repair and add storms or replace, kits or units?

Also, when retrofitting basements I understand the insulation details for walls but how should the existing concrete floor be handled in a 1950-60's home? The basement will remain a basement, usable space other than storage anticipated.

In Energy efficiency and durability | Asked By Glenn Berger | Oct 17 12
2 Answers

Are there any issues with Spray-foam next to Batt insulated walls?

We have a project where we there are additions and renovations to an existing residence that has batt insulation throughout. We have specified closed cell spray foam insulation to be used in the addition walls floor and sloped ceilings and batt in flat ceilings. In the existing part of the house where some exterior walls will be renovated we have specified spray-foam. The remaining existing house will not receive new insulation. My questions is, are there any issues with condensation using both insulation types adjacent to each other?

In Green building techniques | Asked By Martin Brown | Oct 31 12
6 Answers

What can be installed to feed air to my house when the fire place is operating?

I have constructed a new house that is tight. I have both a fireplace and wood burning stove. I have trouble establishing flow when lighting the woodstove when the firepalce is operating. The air is being pulled down the woodstove flue with burning newspaper placed at its opening. I have to open a window in the house to get the air to move up the woodstove flue.

In General questions | Asked By Tom Tyrrell | Oct 30 12
12 Answers

Looking for an effective R-value for polyiso as outboard insulation

I live in zone 6 (and not happy about it). I was looking for an effective R-value for polyiso as outboard insulation over 7/16 OSB, 16'' O.C. 2x6 stud wall with high density cellulose. R-value needed.
Paul (new to site and love the reads)

In Energy efficiency and durability | Asked By Paul Falcone | Oct 24 12
13 Answers

How to get the best out of a thermal imaging visit

I have a contractor coming around in a few days to do thermal imaging on our house with and without a blower. He's going to visit at 6am so we should have at least 10C difference between inside and outside and no direct sun since the day before.

In Energy efficiency and durability | Asked By David Coote | Oct 22 12
3 Answers

House tightness

Is there any thing in the code (North Carolina) that states the ventilation, natural or mechanical, is at an acceptable rate. I have ran a blower door test on a new residential and got 867 cfm50 with 2.95 ACH50.

I don't think that there is any thing in the code but I want to make sure that the house is safe regardless of the code requirements.

In Building Code Questions | Asked By Matt Edwards | Oct 29 12
3 Answers

Outside Combustion Air

My daughter has an 1860's vintage house in New Bedford, MA with a hot air heating system. She has a damp and moldy basement which supplies the intake air for furnace. Can we easily install outside intake air to supply return duct and does it need any special equip. besides a vent hood and duct? Would it replace the damper attached to return duct? She has a new baby and a 4 year old and we are concerned about moldy air being sent to living space.

Thank you


In Energy efficiency and durability | Asked By Fletcher Hall | Oct 29 12
3 Answers

Can cellulose be too fluffy?

During one of my frequent visits to this area of the site, one of the discussions revolved around, to quote Martin "the slight performance degradation of very fluffy insulation on the attic floor due to wind-washing and internal convection currents, especially in very fluffy fiberglass insulation at very cold temperatures". My question comes from my recent experience of removing my cellulose insulation and blowing it back in after spraying ccSPF on the attic floor. The re-used cellulose insulation seemed much fluffier than the supplemental cellulose I installed.

In Energy efficiency and durability | Asked By Pete Marthaler - Zone 7 | Oct 29 12
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