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11 Answers

TwinFresh Comfo 32 CFM Power 5 in. Single-Room Energy Recovery Ventilator

I just took ownership of the first HRV to be sold at Home Depot. I love it.

Price $475

Extra stuff I learned about it:

1. The 16cfm mode (perfect for a 2 person bedroom) is only 0.3 sones at 4 watts. Almost inaudible.

2. Low speed is 8cfm (the one person setting) is 0.1 sones which is TOTALLY inaudible.

3. It can cycle on humidity if desired. That is, it will come on when the humidity reaches 40%RH (low), 50% (medium), or 60% (high). When the humidity drops below the setpoint, it shuts off.

In Mechanicals | Asked By Kevin Dickson, MSME | Jun 6 14
6 Answers

Canned foam not airtight?

Is there more information regarding whether canned one part foam is airtight? Is there a study done on this? I believe it was mentioned in the cut n cobble blog. Is one brand better than another? Is window and door low expansion better than crack and gap/fireblock? I currently use the Great Stuff Pro brand due its the easiest to get at the big box stores. Any info would be appreciated!

In General questions | Asked By eric nutis | Dec 6 13
1 Answer

Killing mold

I had a bathroom mold problem and told my apartment supervisor about it. They came and cleaned it out and now they want to leave a fan on it over the weekend to dry it out after they coated it with chlorine bleach. That seems like too much time to dry to me. Or are they doing it right?


In General questions | Asked By Sheleen Feldhaus | Jun 20 14
3 Answers

Foam in attic

My geothermal HVAC contractor also does foam insulation. He says rather than encapsulating the attic by spraying under the roof deck, he uses deck shield on the roof then sprays foam on the attic side of the ceiling Sheetrock. He said makes a more efficient home as well as being more comfortable andit takes less foam therefore some less expensive. Any yeas or nays?

In Energy efficiency and durability | Asked By Rus Pearson | Jun 19 14
5 Answers

Radiant or Forced Air Minneapolis

Ok guys what do I do here is my situation haven't started building yet but this is what I'm dealing with...

-80x52x20 slab on grade well insulated barn type building going with a BSC type building approach
-52x35 two story home inside open floor plan with bedrooms upstairs, remaining 45x52 for shop/garage space heated to around 35-40 degrees in the winter
-my wife doesn't want ductless minis doesn't like the look
-there is natural gas available on the property was thinking of doing a boiler for both dhw and radiant heating
-two stage/speed regular natural gas furnace

In Mechanicals | Asked By Ryan Picha | May 7 14
9 Answers

Hip roof that intrudes into living space: "hip ceiling"?

I'm in Massachusetts (zone 5A), and have a 1960 garrison colonial with a 6:12 hip roof. I'm looking to do a lot of insulation/venting/roof work, and am about to post a detailed question. But, before I do, I need some terminology.

In General questions | Asked By Daniel Griscom | Jun 19 14
6 Answers

Priming the back of wood siding

I have heard that it is necessary to prime the back side of the spruce clapboard that I am installing on my house in order to prevent rot. I do plan on having a 1/2-3/4" air space in between the siding and house wrap. Is this extra step necessary? Lots of labor and extra paint I'd rather do without. On the outer surface I will be sealing the knots with BIN oil based stain blocker prior to solid stain application. Thanks for your help.

In GBA Pro help | Asked By Matthew Michaud | Jun 19 14
5 Answers

Is it okay to put an unvented hot roof under a wood shingle roof?

I have a wood shingle roof directly over tongue and groove sheathing. Can I put an unvented hot roof under the shingles? My plan is to put five inches of ISO directly on the underside of the sheathing. I cannot find anything on the Internet that discusses this issue. I live on Cape Cod. Thank you for your help.

In General questions | Asked By Randy Aubrecht | Jun 18 14
4 Answers

Pier and beam foundation in Climate zone 5

I'm planning to build an efficient house in southern Ontario, and am looking at different foundation options. Any feedback would be greatly appreciated.

Here is one approach I'm considering: pier and beam, with deep open web floor trusses resting on the beams. The underside of the trusses would be sheathed in plywood. My preferred insulation, at this point, is dense packed cellulose insulation. I would use floor trusses at least 18" deep. Airsealing would be a high priority.

In General questions | Asked By Graham Fisher | Jun 19 14
2 Answers

Foam insulation

Building a home soon. My contractor says he uses closed cell foam on the outside of the blocks below and above grade on the walk out basement for insulation and to seal against water penetration into the basement. I,m concerned that the foam will not hold up below grade allowing water into the basement. If I'm wrong, won't I still need french drains around the basement to keep water pressure off the block walls. or should I use Block-Out on the outside and put the foam on the inside between the studs.

In Green products and materials | Asked By Rus Pearson | Jun 19 14
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