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3 Answers

Cheapest Energystar HRV

Looking to quickly find the cheapest possible HRV that has an Energystar rating and can flow 120cfm. No other specs matter. Preferably a unit I can buy and install myself, since that's going to be a huge cost penalty. Any advice appreciated.

Asked By Trevor Lambert | Apr 26 18
19 Answers

Heat runs to unfinished basement? Pacific NW area

I realize the basement is considered part of the conditioned space, but I was a little startled at an HVAC guy proposing to cut heat runs into the basement (which we do not plan ever to finish). It's a 1901 basement with concrete walls to ground height and wood joists above that. Previous owners had put fiberglass insulation in the joists, which was a really bad idea as one can see from old water stains. That's long gone, but when we first lived in the house we used to get water coming up through the floor drain during storms (no leaks through the walls that I am aware of).

Asked By Irene3 | Apr 20 18
5 Answers

Air Tight Envelope with in Ceiling Speakers

Climate 6A. Planning on a pretty good house. R-60 roof, R-30+ walls and less than 1.5ACH50. We're planning an un-vented cathedral roof with low slope (2.5/12).

I have already specified no canned lighting in my ceiling but I just got to thinking about having in-ceiling speakers. I assume they are as bad or worse for air sealing and stack effect into my rafter bays?

Is there such a thing as a well sealed in-ceiling speaker or should I be looking at other options? Any recommendations?


Asked By Steve Mackay | Apr 26 18
0 Answers

Sloped ceilings from inside: Removing drywall

We just uncovered the final instance of corner-cutting by a local/franchised insulation contractor. (T Carlson, this is the same project you and I discussed, but the situation is messier than previously thought). Rather than insulate the entire sloped ceiling between the kneewall and the top attic, this group only insulated the top portion and left the lower 3 feet of sloped ceiling entirely uninsulated (and hidden). This unscrupulous crew made a conscious decision thinking we would never notice.

Asked By Emerson | Apr 26 18
14 Answers

Heated bath floor - system and flooring?

Is there any metric by which to measure the efficiency of electrically heated bath floors? Is there any system that if preferable to others? What about the Schluter Ditra system? If you have one, would you do it again? If so, what would you change about how it is installed?

Asked By c l | Apr 23 18
3 Answers

Building wood stain

Can anyone help explain what would cause a stain like his. It’s on treated wood. Almost like a chalk stain, but does not rub off. I have a few pieces like this.

Asked By Birdie L | Apr 26 18
2 Answers

Inadvertent vapor barrier?

I live in MN and have a 12'x16' porch addition that I'm about to insulate the vaulted ceiling. I'm calling the porch a 3-1/2 season porch since I'm installing electric base board heat which allows me to heat the room, but only when I intend to use the room, which may not be that often in the dead of winter. The scissor trusses are just 4/12 exterior pitch with a 2/12 vaulted ceiling and 7" heel height at the wall line, so not a lot of room to meet R value requirements here.

Asked By BobPv | Apr 22 18
2 Answers

HRV / HVAC engineering help in Ontario

My building inspector came to do my HVAC rough-in inspection today. After he had ignored my e-mails and phone calls for 2 months, I gave up and just bought the Zehnder unit I wanted. The last thing he had said to me was he was "sure it would be fine", and he'd call me back in half an hour (which he never did, called him again and got another promise of a return phone call that never happened). So now he claims he sent an e-mail telling me the Zehnder didn't meet the Ontario building code, and needs a report from an engineer to allow it to pass.

Asked By Trevor Lambert | Apr 26 18
9 Answers

Insulating and air sealing attic in a 1930s colonial

I recently moved into a brick colonial in the DC area built in 1935. It's heated by a boiler through radiators and has a 25-year-old A/C unit in the attic. It has a slate roof and gable vents, but no soffit. The blower door test showed that it's quite loose, which is no surprise.

Asked By Jeremy Good | Aug 2 17
4 Answers

Cold pantry in a Passive House via hot water heat pump air exhaust

We're building a passive house and one thing we had to give up was the idea of a cold pantry for long-term storage of root vegetables, apples, etc. But after learning about hot water heat pumps and the fact that you can duct the cold exhaust air, I started thinking it could be possible exhaust the cold heat pump air to the pantry. The pantry would have to be tightly sealed and insulated and have a returning duct back to the mechanical room. That would essentially create a cool, dry cold pantry with constant air circulation.

Asked By Mike AbiEzzi | Apr 25 18
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