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2 Answers

Can a whole house attic fan help lower radon levels?

I have a passive radon system installed in my house that is semi blocked. Mitigation brought it down to 5. Will an attic fan help or hurt ??

In General questions | Asked By Gale Oleary | Oct 22 15
4 Answers

Please recommend an HVAC system for retrofitting a 2-unit Victorian in San Francisco

Both units in my building currently have natural gas wall panel heaters.

In Energy efficiency and durability | Asked By Pamela Faulk | Oct 19 15
4 Answers

Rain screen

Hey guys...I've got some cedar lap siding installed over 3/4" rainscreen, gap at the top and bottom of the wall. This is all installed over 2 1/2" of ISO, tyvek, sheathing in that order. Soffit overhangs are 3'.

In General questions | Asked By Stan Smith | Oct 21 15
4 Answers

ECM, variable-speed, multi-stage confusion


I'm confused about the words ECM, variable speed, and multi-stage. If anyone can offer definitions, that would be very helpful.

If I buy a furnace that is labeled as having an ECM (according to the AHRI certificate), is it necessarily a variable speed motor? My understanding is no.

What about the reverse? Are all variable speed furnace motors ECM? Maybe...

The word "multi-stage" has nothing to do with the motor, correct? That has something to do with the number of burners on or amount of gas being burned, right?

In Mechanicals | Asked By Whitney Larsen | Oct 20 15
3 Answers

How do I make an airtight ceiling if it's rough sawn exposed beam construction?

I've got a camp in the woods that I'm adding a room onto. I have dug the foundations and constructed the walls. I just watch Dr. Joe's video on roof venting and he says that the number one rule is to make an airtight ceiling. The trouble is that I have a rough sawn hemlock ceiling with exposed joists. I am intending on leaving it unfinished to fit the more rustic look of the camp. Can I lay poly on the top of the ceiling deck (the attic floor) to make the ceiling airtight or will that create vapor issues?


Mike in Maine

In Green building techniques | Asked By Mike in Maine | Oct 21 15
4 Answers

DIY walk-in cooler in basement

I would like to build a walk-in cooler in the basement of my home. I plan to insulate to >=R25 on walls and ceiling and I thought I had a good plan for insulation until I considered vapor diffusion. The space will be in the basement which is generally 65-75 degrees year-round and has a RH of 40-50% (active dehumidification in the summer and fresh air ventilation in the winter to maintain humidity).

In Energy efficiency and durability | Asked By Ken French | Oct 19 15
1 Answer

Who makes, supplies, installs replacement fiberglass windows in Toronto high-rise buildings?

My extensive research of the window manufacturing and installation industry has lead me mostly to the low-rise vendors. Some claim they can install their Vinyl windows in any high-rise building (against Fire Code).

Wood and Vinyl (combustible) window frames are not allowed in high-rise construction.

Aluminum frames are strong but have the highest thermal-conductive rating.

Fiberglass have the best energy performance and least expansion / contraction related to glass.

In Green products and materials | Asked By David Froud | Oct 20 15
1 Answer

Adding attic insulation

zone 6 northern NH,single story house, low clearance in attic, only 4 feet at tallest point, so access is poor at best, ceiling is 6x6 beams with 1x10 boards on top of beams,boards are not tongue and groove and have gaps up to 1/2 inch between them, lots of unsealed electric boxes,wire runs, etc.

In Energy efficiency and durability | Asked By Darren Williams | Oct 20 15
6 Answers

Article about PACE green financing program

Reuters has a story this morning under the headline "Green financing has hobbled home sales in California." I found it at http://news.yahoo.com/innovative-green-financing-hobbled-home-sales-cali.... I would be interested to hear other people's reactions to it.

In General questions | Asked By Reid Baldwin | Oct 19 15
8 Answers

Closed-cell foam for existing cathedral ceiling cavities?

I've a 150 year old house with a partial cathedral ceiling covered by plaster lathe, and dry wall on top. There is no insulation at all in the cathedral ceiling bays. I can access the top of each bay from the attic, and the bottom of the bay via the knee wall - is there a closed cell foam solution I can use which would not require me to tear down the approximate 8 linear feet (each bay) of ceiling, without blowing out the plaster? Thank you - Jim

In Energy efficiency and durability | Asked By Jim Berry | Oct 18 15
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