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3 Answers

Sizing a heating and cooling system

We are finalizing designs for the mechanicals and I am looking for some advice. My mechanical engineer is doing all the Manual J, D, S, and HERS calculations. On my side, I am running the WUFI analysis. We are going to spec a combination of ducted, non-ducted units working off of a single VRF ASHP. Some of the questions I have are as follows:

1) Does anyone have any experience with regards to which sizing tool is more accurate in a very well insulated house, Manual J or WUFI?;

Asked By Jonathan Lawrence CZ 4A New Jersey | Oct 24 16
8 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

Cedar siding installation

Ok..getting around to siding and what a nightmare trying to decide what to use for siding. We really would like a natural look and natural cedar comes in at about 1/2 the cost of LP smart siding and my understanding is smart siding is not installable over furring strips. I would like to install the cedar OVER the existing asbestos cement siding as to limit the massive labor and possible danger of removing the current siding. My questions are:
1. Do I have to locate the studs to mount the furring strips? The house is 135 years old and has 1" tng sheathing.

Asked By Geoffrey Cook | Oct 24 16
12 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
72 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
6 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
39 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
2 Answers

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
3 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
1 Answer

Insulate attic to prevent pipes from freezing

Long story short: We have pipes running through the attic of our garage to an addition. The pipes run close to the roof line and then go down an outside wall. The attic rafters are not insulated and the walls above the ceiling line are also not insulated. The floor of the attic where it goes over the house is insulated. The attic portion is open to the garage itself (its kind of like a crawl space), but the pipes will freeze at anything below 32 degrees, so clearly heat is not getting up to the attic from either the garage or the house.

Asked By Lindsey Carden | Oct 24 16
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