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0 Answers

Low profile cans /speakers below closed cell in a flash and batt roof.

I have a retrofit (zone 4, Humid SE) where we're doing an unvented roof with 4" closed cell SPF and an R-13 unfaced batt.

Contractor and client have been asking to use low profile speakers and can lights below the SPF layer. Generally I have been hesitant to do that as I'm unsure to what extent those penetrations in the G.W.B. will pose issues thermally and hygroscopically But if the foam is very solidly our air/moisture barrier, do I need to worry about those penetrations?

Asked By Chris B | Oct 26 16
7 Answers

More rim joist insulating questions


I know this topic has been discussed a lot, but I cannot find exactly what I am looking for.

We have a 1926 Tudor in Minneapolis, MN. I am in the process of finishing our basement and I plan to use 2" of rigid foam on the walls and potentially between the joists to seal up the rim joist. I may use closed cell spray foam to seal the rim as well. My problem are:

1. We have concrete poured between our joist onto the foundation making it difficult to use rigid foam. The concrete is also poured very uneven. This is why I may use spray foam.

Asked By Joe Sweeney | Oct 25 16
3 Answers

Air sealing attic: materials and fire safety

I'm a homeowner thinking to do some DIY air-sealing in the attic. I was preparing to use caulk on narrow gaps (top plates), and spray foam on larger gaps (penetrations for cables, plumbing vent stack, etc). Not being a pro, I was going to just stay away from anything thermally hot, like the furnace vent.

Asked By Sam Smith | Oct 25 16
2 Answers

Risky assembly

A friend called me today seeking advice for a new room he is adding to his brownstone. He has an unused space on the top floor and he wants to put a wine cellar there. A wine cellar on the top floor? Not an ideal location for sure. But just for kicks, let's assume he has no floor load issues and he can adequately insulate and seal the walls and floor. What about the roof? Did I mention this space is below and unvented flat roof? So drying to the outside is out of the question. I think the biggest concern is the sheathing.

Asked By Jonathan Lawrence CZ 4A New Jersey | Oct 25 16
0 Answers

Design help for combined DHW and Space Heating


I am finally at the point of my remodel where I can get the mechanical design completed and so I'm following up on my earlier post 'Radiant heat design details - Bosch or Navien combi boiler?'.

Asked By Torsten Budesheim | Oct 26 16
7 Answers

How to insulate a stackboard house?

I have an old house, built in 1840, and with an addition put on around 1900 or so. The original house is stone, and the addition is made from stackboard. Stackboard is a technique locally popular in lumber towns, where you take rough cut 2x4s, stack them on their flat side, and chink in between with 1/2" chunks of wood. Essentially your entire wall is solid wood and you renovate using a chansaw (my grandfather actually did this apparently, as even the interior walls were done this way. it's wierd). The house is pretty much uninsulated other than the thickness of the walls (R1?)

Asked By Terry Sharpe | Jan 4 16
1 Answer

We're preparing to begin an extensive green remodel of our home

We would like assistance in locating a contractor in our area (South Florida). Please share any contacts you may have.

As a new "student" of Green Building/Remodeling, I'm invested in the success of this project for professional experience that I can use in the future.

Asked By Chanda Levy | Oct 25 16
14 Answers

Sun Bandit solar water heater

Hello. I was reading the article by Martin Holladay entitled "Solar Thermal is Really, Really Dead" and enjoyed the discussions going back and forth on the topic of solar water heating methods. I am planning on building a small 600sq' SIP cabin in the area of Nelson BC (climate zone 6) next year and I found this product listed as being one of the most efficient for heating domestic hot water on the Canada Energy Guide site. It says it can also be used for space heating via a radiant floor system or perhaps radiators.


Asked By Scott Wilson | Oct 21 16
75 Answers

While I love radiators, I hate using fossil fuels

I live in an 1890 Victorian in Southern Pennsylvania, heated by oil. While I love radiators, I hate using fossil fuels! Is there a way to use green technology to use less oil? My methods to date have been uncomfortable - installing a wood stove.

Is there a way of boosting the boiler with green energy? Would geothermal help? I'm newly divorced and ignorant about systems!
Thanks, Susan

Asked By Susan Hanway | Aug 28 16
40 Answers

HRV duct set up

I am getting ready to install my HRV. I have been contemplating exhaust in the two bathrooms, three bedrooms, and kitchen area, with only one supply duct in the great room near my mini-split. 1300 square feet, one level, 3 1/2" exterior foam, 6" fiberglass batts, unvented sealed crawl space. The design person at the HRV store is said I should have supply to all bedrooms and just exhaust the bathrooms/kitchen. Climate Zone 7, so I am a little concerned about supplying all that fresh air to the bedrooms in the dead of winter.

Asked By Steve Vigoren | Sep 6 16
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