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3 Answers

Are there any independent reviews for Whole House Fans?

I'm looking for a whole house fan for a 3000 sq ft house. I would like it to have an insulation cap and be as quiet as possible. You recommend the Tamarack line on your site, but I'm looking for more information about brands pros/cons. thanks, Caroline Howell

In Green products and materials | Asked By Caroline Howell | Jan 13 10
1 Answer

Building Science Videos

Here is a link sponsored by the State of Oklahoma

Lots of good videos for all climates INCLUDING Hot/Mixed and Humid
I think all of the videos are over three years old.

I especially like the Joe Lstiburek videos:

and Betsy Pettit videos:

In Energy efficiency and durability | Asked By John Brooks | Jun 16 10
0 Answers

Net Zero in Edmonton

Here is the link to part 1 of six youtube videos that describe what is being learned with the latest and greatest residential housing in one of Canada's coldest climates....10-11000 HDD if I recall correctly. The videos feature Peter Amerongen who is one of the principle designers and the builder involved.

All six videos are there but require a little searching...

In General questions | Asked By Garth Sproule | Jun 17 10
1 Answer

Venting above an Insulated Cathedral Ceiling.

Building with 6" fiberglass insulation in rafter bays in cathedral ceiling on half the the house and 6" fiberglass insulation in the rafter bays PLUS 1.5" ridgid polystyrene pink board on the underside of rafters on the other half. Have had serious problems with ice dams over the years.

Due to storm damage, am going to replace entire roof at this time.

Queation: Would it help to VENT the roof above the insulation, given the different R values of insulation sue to different construction techniques?

In Energy efficiency and durability | Asked By Tom Bickford | Jun 16 10
3 Answers

IMHO Robert's question is... what does green mean?

Green Building. Define it all.... In your humblest opinions.

Green does mean to most sustainability... well to be blunt of the human race... us and our children. It means whatever actions we take today will not impact us adversely now or in the future.

Technology doesn't have to impact us adversely but as Robert points out there is a price to pay for every action we take. Scientifically we know about the laws of thermodynamics, about quatum mechanics... and so much more all in the short span of a few hundred years.

In General questions | Asked By adkjac | Jun 15 10
1 Answer

The use of blown insulation on the underside of a roof that requires a fire resistance rating

We are looking for advice for insulating the roof in a renovation of a curling club in Toronto. They are looking for blown insulation for the underside of the roof. The goal is avoid covering it with GWB for fire protection due to deadload concerns. Monoglass has been suggested, which is a blown fibreglass product that is apparently green and does not require GWB to protect it from fire. We have manufacturer’s literature and an NRC reference to a study underway, but nothing “impartial”.


In Green products and materials | Asked By Michaela Jones | Jun 15 10
1 Answer

Is it required by residential Building Codes to have air vents on top of garage?

I'm currently selling my 5 year old home (built in 2005) in Houston, TX and buyers had a 3rd party TREC inspector come out to perform routine inspection and he noted that since the attic over the garage is seperate than the house attic, the current soffit venting is not sufficient and is required to have additional ridge venting or something equivelent exhaust the air.

In Building Code Questions | Asked By Jason Manhold | Jun 15 10
2 Answers

hvac return

i inspected a building with two returns in a 463sf hallway ceiling and supply registers in every office space of a 3399sf cinder block building with doors shut most of the time. it's hot in the summer and cold in the winter. should i install transfer grilles in the doors or cut the doors? do transfer grilles work just as well when installed in a door?

In Energy efficiency and durability | Asked By silas | Jun 15 10
5 Answers

Is it safe to put a poly vapor barrier over an old roof when insulating?

I have a 2 X 6 T&G wood cathedral ceiling, with 20 year old asphalt shingles on it. I built a new steeper roof with space for insulating above it. I prefer not to remove the shingles which were left on to protect the house while the new roof went up. I am insulating and air sealing and am putting a poly vapor barrier over the old shingles before adding about 18" insulation. Is there any chance the old shingle layer could create indoor air quality problems being under the poly layer?

In Energy efficiency and durability | Asked By Rich Gady | Jun 14 10
2 Answers

Should fiberglas insulation be removed before spraying foam?

The house in question is 1950's flat-roofed split-level house, with a built-up asphalt roof.
The roof leaks and the contractor plans to remove all the asphalt and the sheathing and spray foam to increase the insulation value. Presently there is a layer of fiberglass in the 2x10 cavity.

In General questions | Asked By DAVID FROEHLICH | Jun 13 10
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