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1 Answer

Will "Roof Melt" chemically or physically damage an asphalt roof?

In addition to questions concerning its chemical impact on an asphalt roof, is it effective in reducing the ice and snow on this roof?

In General questions | Asked By JOSEPH POLAND | Feb 21 15
2 Answers

Is there a way to provide geothermal HVAC to a rim joist in order to keep the rim dry?

I have a Rim joist that was just above grade sitting behind a 5" concrete lip ... presently i have waterproofed exterior foundation wall, rock from footing up to sill plate, sill is sitting 6" above grade right now ... though 2 feet out from wall the grade rises 1 ft. I am contemplating ways to run radiant tubing behind the Rim joist and sil plate in order to keep them at a desired emulated ambient temperature, pulling water from geothermal pump, in order to avoid condensation.

In General questions | Asked By Jon R | Feb 19 15
8 Answers

Zone 5 Envelope Enclosure / Parallel Chord Truss

I'm will be building a home this summer / fall and have started working out the details for my build.

I'm in zone 5, BC, Canada, and intend to build a simple shaped gable end structure with cathedral ceilings. I've located a truss manufacture who can build parallel chord scissor trusses for me that will meet my 20' span without a ridge beam.

In Energy efficiency and durability | Asked By Jeff Pepperdine | Feb 12 15
10 Answers

Details of the "Dumont Window"

I wish to construct an R-40 Wall with Brick Cladding, a 1" Drainage Space, 3" of Foil Faced Polyiso, the Control Layers, ½" Plywood Sheathing, a 2X6 stud wall filled with insulation, and ⅝" GWB. Into that I would like to use a so called "Dumont Window" (see attachment) so named for architect Robert Dumont of Toronto. Does anyone have details of that window which I could provide to my builder ?

In Green building techniques | Asked By Ted Cummings | Feb 19 15
49 Answers

I have been reflecting on heat pumps in general lately

After reading "Solar thermal is really, really dead," which produced quite a reaction, is it possible that heat pumps themselves are at least wounded?

PV at $3.50 watt installed... Note that heat pumps are still great for all places where PV is impossible.

In Energy efficiency and durability | Asked By ven sonata | Feb 4 15
26 Answers

Most cost-effective whole house ventilation solution for Massachusetts?

I am building a Tier III home on Cape Ann and will be having a single minisplit heat source for my open kitchen/living/loft area with 2 bedrooms and a bathroom also downstairs (896 sf downstairs). I have read all the discussions regarding exhaust only ventilation vs HRV/ERV. There are many HRV systems out there at varing costs. I am trying to find the most decent cost effective solution to whole house ventilation. I was considering Lunos fans but have heard that white noise could be an issue. I am looking for quiet and also cost effective to run over time as well.

In Mechanicals | Asked By Victoria Williams | Feb 19 15
6 Answers

Are 1 heat pump with 3 multiple indoor unit Hyper Heat minisplits available from Mitsubishi yet?

I have a really simple question. I have installed a ductless mini split in my studio, but have been waiting for Hyper Heat units that can handle multiple zones to be on the market (1 heat pump w/ 3 indoor units) to be on the market to put them in my home. Mitsubishi website seems like they're out now. Anyone know for sure?

In General questions | Asked By DANIEL GOTTSEGEN | Feb 20 15
5 Answers

Any idea how to fix this?

I was digging the flower beds and discovered this in the fall. The original dirt level was about to the asphalt shingle shown. I have no idea why its there but from the inside of the house i have some pics in the wall where theres the same type of asphalt in the foundation or just above it, it was hard to get a pic but if anyone is interested i can dig it up.

A few weeks later when there was heavy rain water was coming in at a good clip as you can see in the basement pic, i suspect its coming in under the mudsill and through some plaster (parging?) before the dirt trails shown.

In General questions | Asked By Alan B | Feb 21 15
11 Answers

Will a minisplit with an air handler be adequate for Zone 7A?

I am building new construction with SIP walls in NW Wisconsin zone 7A. House will be 2000 sq.ft. single level with an insulated basement. I am interested in heating with a Mitsubishi minisplit using an air handler to distribute air throughout the house in a ducted ductless mode as seen on Ask This Old House feb19, 2015. The handler has backup elec. resistance heat for a heat boost when needed. Three basic questions.1 Will this be adequate to heat this house? 2. Can the air handler be mounted in the basement to distribute air and can we avoid having the units typically mounted on walls 3.

In Energy efficiency and durability | Asked By terrance kaase | Feb 19 15
3 Answers

Insulating outside wall against moisture

I have an outside wall with soil piled up due to grading against a wall. I heard installing an "insulation curb" would help. What kind of people should I hire to re-work it and install "installation curb"?

In Building Code Questions | Asked By Anthony Ng | Feb 18 15
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