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6 Answers

Brick building - lots of heat emanating from bricks on warm days?

I live in a masonry/brick house, where the exterior walls are 2-bricks deep & the floor joists sit in slots between bricks.

While cutting the grass in the evening on a day in which it was pretty hot in the afternoon (90+ degrees), while hitting the grass up against the building, I could literally feel heat emanating from the bricks as if there was a fire on the other side (the interior). The brick did not necessarily feel hot to the touch, but it was if the air directly over the brick gave off heat with no obvious source. Is this just an observation of thermal mass in action?

Asked By j pritzen | Jul 30 16
7 Answers

Floor insulation for a tiny house on wheels


I'm beginning to build a 24' tiny house on wheels, and I was hoping that someone here might be able to answer a few questions I have about the floor framing and insulation. I’m trying to devise a floor system that saves on height (I’m limited to a max of 13’6” to be road legal) and avoids thermal bridges. I plan on insulating within the trailer frame with 3" foam board between the metal runners (with aluminum flashing on the underside). However, that still leaves about 3” along the perimeter where metal would be in direct contact with the plywood subfloor. Here’s my question:

Asked By Fallon Abel | Sep 20 15
1 Answer

Has anyone used a WhisperComfort™ Spot ERV Ceiling Insert Ventilator FV-04VE1 in high performing home?

Will this inexpensive simple to install recovery ventilator work placed in a central location of a 1500sf house -- mostly ceiling on the second floor with 1-1/2" bedroom door undercuts and the whisper green motion sensor activated bath exhaust fans or is that delusional? I am in zone 6 thanks

Asked By susan cosentini | Jul 30 16
1 Answer

I plan to build a passive solar, earth berm home , having trouble finding out how big (diameter) and length of the earth tube to ventilate a 1500 sq ft home

Home is open design with concrete floors and walls with exterior insulated

Asked By Thomas Rzepka | Jul 30 16
6 Answers

Help with old building in Michigan

I’m looking for some advice on how to properly sheathe and insulate exterior walls on an old commercial building. The property is in Ludington, Michigan (Zone 6) and right now (from the inside out) there are 1” pine boards, actual 2”x4” studs on 16” centers, no insulation, and old cedar clapboard siding.

Asked By Edgar Struble | Jul 29 16
0 Answers

Installer for spray foam insulation, Eastern MA / greater Boston area

I'm looking for a reputable installer for spray foam insulation (closed cell foam) in the Eastern Mass / greater Boston area.

More specifically, I had foam installed in my attic last summer (August 2015) and I suspect something went wrong with the job.

I'm looking for reputable installer to take a look at my attic and provide a 2nd opinion on the issues I'm seeing (*). Can anyone recommend someone?

Asked By Steve Hirsch | Jul 30 16
2 Answers

Need help with our ductwork decision

I contacted a reputable contractor to come do a duct test and take a look at our attic insulation. The ducts are very leaky and most of them are the old grey kind and some are not in the best shape. One even was missing all the inner plastic and all you could see was the metal ribbing and fiberglass.

Asked By Blake Lasslett | Jul 29 16
2 Answers

Double wall opening detail


I am embarking on my first energy efficient home in Maine for my own residence. Walking away from the Code Built norm finds me scratching my head a bit.

Double walls at 14", 2X6 and inner 2X4. Stem walls and footing with an insulated and thermally broken floating slab system.

Sill pan recommendations for the door breaks where they will contact directly with the concrete stem wall? I will be using an EPDM sill gasket/10 mil poly/tremco sealant sandwich under all the sill plates and I assume under the thresholds of the many doors.

Asked By David Chapman | Jul 29 16
1 Answer

Interior vapor barrier

We had one room remodeled. One west wall (upstairs),one north and south wall now has outside insulation, fiberglass interior, poly sheet vapor barrier, and dry wall. Now I am wondering if we need to remove it. It is only in one bedroom, but I read your article and now I am concerned. Please give your thoughts. Thanks.

Asked By Phette Place | Jul 29 16
1 Answer

Which way should the polyiso foil face when installing over drywall?

I plan to install 1-1/4" polyiso foamboard over existing drywall, then 3/4" furring strips, then 1/2" of drywall. Should the foil face towards the interior or the exterior?

If it matters, this is for Austin, TX 78722 where we need more cooling than heating, and I'll be using two layers of polyiso (1/2" + 3/4"), because I can't find 1" polyiso locally. I do plan to tape the edges to prevent degradation of the foamboard. Thank you for your help.

Asked By Michael Bluejay | Jul 30 16
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