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38 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
3 Answers

Insulating 2x6 cathedral roof

Just read "How to Build an Insulated Cathedral Ceiling" trying to apply to my gut rehab project.
Zone 5a, house has a hip roof framed with 2x6. When I tore drywall off, found vented eaves with no venting on roof. Insulation was 6" fiber glass bats tGN#?with no air channel space. Roof has brand new shingles so I want to insulate from below. I am thinking non-vented roof, fill 2x6 void with closed cell foam and then install 2" foam on studs for thermal break. Does this sound like correct strategy? Should I install vapor barrier below foam board before drywall?


Asked By Steve Karkau | Oct 23 16
2 Answers

Foam sheathing insulation on basement block walls

Building a new home in Syracuse NY. We will have two bedrooms in the finished basement (not walk out but large egress windows). I want to use foam sheathing on the concrete block walls - primarily as a vapor retarder but also for it's insulating value. I have read differeing opinions on the ideal permeability rating for foam in this situation. BSC says to keep it permeable but I have read elsewhere (here maybe) to use impermeabile. I have my eye on 1" XPS because Lowes has it in stock.

What do people recommend? Thanks

Asked By david schreiber | Oct 23 16
5 Answers

Heat with a minisplit in Ontario

I'm looking at replacing my HVAC system this year. I live near Peterborough Ontario. Currently my system is composed of a 60 year old oil boiler, a wood stove and portable AC units in bedrooms. I had previously asked a question http://www.greenbuildingadvisor.com/community/forum/mechanicals/98848/re... about a boiler.

Some information from that post that is relevant here:
Using bills for oil from last year I calculated my heating load (@ -4F) to be 22000 BTU/h. Basement, addition and main home have been spray foamed. There is R50 in the attic.

Asked By Joe McRae | Oct 23 16
1 Answer

Insulate existing garage walls?

I have a house in Houston with drywall already installed on all 4 walls of a 2-car 22'*25' garage. Two walls are shared with conditioned space and insulated. One SW facing wall has no insulation, and the NW facing wall is 90% insulated garage door, the remainder uninsulated.

The uninsulated SW wall (afternoon Texas sun) actually protrudes into the conditioned house, so only about 15' are uninsulated. The garage ceiling is not currently insulated.

My goal is to make the garage a little cooler in the summer and a little warmer in the winter. I do not plan to add HVAC.

Asked By Mark McFarlane | Oct 24 16
2 Answers

EarthPaint Products

Is there a reason that none of the various products sold by EarthPaint are not consider "green" by Green Building Advisor?

A review of their materials: no petroleum products, low- or no-VOCs, etc.

What am I missing? Thanks.

Asked By Andy Kerr | Oct 23 16
66 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
4 Answers

Best practice for stone siding over stick built walls

We are planning to apply 4 inch thick rubble stone siding over the lower level of our daylight basement home. We had originally planned for ICF at the lower level walls, partly to mitigate rain water and inward vapor drive risk brought on from the stone (which is south facing). As it turns out the ICF represents a substantial cost increase and we are considering alternative wall options (stick-built) for the above grade portion of the lower level wall.

Asked By Sean Hembree | Oct 22 16
1 Answer

Insulating a flat ceiling in conjunction with a hot roof?

Hey there... My 950 sq ft. house has a hot roof insulated with 4.5" of spray foam. The roof system is 2x8 rafters with 2x6 collar ties. The attic space is basically a crawl space. I'm planning by adding insulation to the flat ceiling using 5.5" of rock wool. I currently have zero moisture issues in the house and heat with wood, generally keeping the house humidity pretty low. Am I doing anything bad by adding the insulation to the flat ceiling?

Asked By Todd Loiacono | Oct 23 16
8 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
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