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0 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
36 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
7 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
3 Answers

How much insulation for a steel beam?

How much insulation do I need over a steel beam to stay above the dew point inside the house?

This is new construction in progress, in NC. The I beam is over a door and window assembly and contained within the wall, sandwiched between the sheathing and drywall. However, no consideration was given to insulating it in the design.

Asked By Jeremy Turner | Oct 22 16
0 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

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
2 Answers

Domestic hot water power demand is no longer an issue?

Traditionally, heating and cooling requirements have been the largest energy draw in homes. The ability to relegate heating and cooling to 2nd or even 3rd place in a home energy draw hierarchy is now possible with better building techniques, such as PH. It has been generally agreed that the new king of the draw is DHW. However, I wonder if that is still the case now that HPHW systems have hit the market. I live in a heating dominated climate. The maximum heating demand allowed per PHI is 4.75 KBtu/SF or 5.2 KBtu/SF per PHIUS+ for my climate zone.

Asked By Jonathan Lawrence CZ 4A New Jersey | Oct 22 16
65 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
0 Answers

water furnace 7 series desuperheater

So i am in the process of having installed 3 water furnace 7 series with desuperheaters. Trying to figure out hot water options. Main side of the house, Im thinking a marathon storage tank heated from the desuperheater. This would feed a 80 gallon heat pump water heater.

Asked By dean sandbo | Oct 23 16
2 Answers

Siding with a step

I have an addition that I have added to my home and am now in the process of finishing up the furring for the rain screen and getting ready to install siding.

The issue I've run into is that I am using vinyl siding to match the original house, but the addition has a basement and the main portion is slab on grade. Because of this, the addition has a rim board that extends roughly 12" below the original slab/sill plate line.

When I go to install vinyl siding the starter strip on the old portion will not line up with the addition.

Asked By Mike M | Oct 22 16
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