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2 Answers

NEW mini-split from Mitsubishi...is it here?

I read here (I think......could be wrong though since I have been everywhere on the net looking for answers before I settled here).. that Mitsubishi was going to release a multi-head ASHP this year (2015) that is still efficient to -25c in an effort to tap into the US residential heating market.
Is it here? Is it coming?

In Mechanicals | Asked By tim brown | Feb 2 15
1 Answer

Moisture behind insulation

I notice moisture behind the insulation on the plywood in my basement. Any ideas what would cause this?

Thanks for any help


In General questions | Asked By Greg Adler | Feb 2 15
4 Answers

Will adding more insulation in basement create a problem?


I've got a large basement space which I'm renovating into a living area. It's in zone 5, Ontario, Canada.

Floor, and Lower 2/3 of walls are bare concrete, upper 1/3 is fiberglass insulated stud wall with drywall.

Walls had been insulated with 1-1/2" of paper faced fiberglass bats between furring strips on which hung wood paneling. Paneling and fiberglass have been removed after 20-30 years, without any signs of mold.

In General questions | Asked By Richard Baumgarten | Jan 26 15
1 Answer

Expanding and renovating in zone 7.

first post here...

I have an 800 sq ft home located in NW Ontario Canada (P9N0E7) zone 7 built late 1990s. The basics..

Fuel oil $1.16 litre when last purchased. Predicted to ???? in five years .
Electricity 21 cents a delivered KWH , time of use metering designed to make sure actual use is during peak periods Predicted to double in 5 years.
- 2x6 construction 16" centers.
- R20 fibreglass batts in stud bays
- Wall stack up is typical for this area, 1/2 drywall, 6 mil poly,R20 insulation (fibreglass) 1/2" plywood, vinyl siding.

In Green building techniques | Asked By tim brown | Feb 2 15
2 Answers

Using rigid foam on a concrete block house - Northern Ohio

I currently have a 1947 one story - exterior concrete block house(2000sf) with 2X2 interior framing filled with batt insulation. That is covered by a mix of wood paneling/drywall. The front of the house already had a 4 inch styrofoam with a textured stucco put on before we got the house. The block exterior is going to need to be painted this year if I don't do something. I do not think it was every sealed/primed/painted correctly as paint is popping off. If I do paint it correctly would I now create a moisture issue?

In Plans Review | Asked By Tim M | Feb 1 15
5 Answers

Advice for basement wall and flooring on an uninsulated basement slab

I am insulated a basement with a very low head room and cannot add any insulation to the floor. I am insulating the exterior walls and I have a trench drain and sump on the interior perimeter of the basement. This had been installed before moving in to the house. No water has shown up in the basement in the last 4 years.

The walls are fieldstone and I intend to use spray foam and provide a dimple mat along the fieldstone wall to funnel any water into the trench at the perimeter. Not sure if this dimple mat should go up the side completely or not.

In Green building techniques | Asked By E M | Jan 22 15
1 Answer

Help with wall details

We're in a maritime climate on the west coast of Newfoundland, Canada. Climate is zoned as 6 but we have mild winters with averages around -10 C. We get warm spells followed by cooler days, not your average climate 6 winter. We heat with a wood and electric furnace.

Contractors have left us with 1/2" spruce clapboard, 3/4" rain vent, 1" rigid foam (classmate, perm of 1.0), osb sheeting, 2x6 stud with R20 batts. The plans call for poly before T&G pine... But after reading a few articles and the potential for osb turning to oatmeal: we're concerned!

What would be the best way to proceed?

In Energy efficiency and durability | Asked By OLIVIER van lier | Feb 1 15
2 Answers

How to insulate valleys in a cathedral ceiling to avoid ice dams?

We're in a maritime climate on the west coast of Newfoundland, Canada. Climate is zoned as 6 but we have mild winters with averages around -10 C. We get warm spells followed by cooler days, not your average climate 6 winter.

In GBA Pro help | Asked By OLIVIER van lier | Feb 1 15
3 Answers

Adding A/C to 1918 built home

My husband and I own a 1918 built foursquare home. We currently use a single 8000 BTU window A/C unit to moderate the worst of the summer heat in our zone 4 climate (Minneapolis). We have discussed installing a split A/C system or small duct central A/C system on the first two floors our home. I think I have a good grasp on the split A/C systems but know less about the small duct systems. I like that the small duct systems have less impact on the look of the house. From what I understand, attic installations are fairly common with these.

In Mechanicals | Asked By Brian Forney | Jan 31 15
3 Answers

Does code require fireproof caulk around electrical boxes & light switches?

We had a blower door test on our house following a major renovation (ACH50 = 4.56 on a 1920s Bungalow, Zone 2A). Several leaks identified, along with my plan to airseal them:

1) Electrical boxes & light switches (photo attached) - Caulk the gap between the electrical box & drywall, add a foam gasket behind trim plate, caulk plate to wall (on inside) & install child safety plugs in unused outlets

2) Base of interior door jams (photo attached) - Caulk

3) Exterior door weatherstripping (copper) - Bend back the copper for a more rigid fit

In Building Code Questions | Asked By Robert Hallenbeck | Jan 31 15
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