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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 ?

Asked By Ted Cummings | Feb 19 15
12 Answers

Basement is too cold, need help in insulation

I live on the border or CT and MA. My basement is around 47 degrees. I have my basement roof insulated with R30 batt insulation. When I measured the temperature of my basement walls, above grade part is coming around 35-40 degrees and below grade is about 40-45 degrees, my basement floor is around 45-50 degrees. I put durashield paint on the basement walls to prevent from moisture ( I did not have too much moisture but I still wanted to avoid any future issues), similarly I painted my floor with two part epoxy.

Asked By Amit Jindal | Feb 16 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.

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.

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?

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.

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.

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"?

Asked By Anthony Ng | Feb 18 15
9 Answers

Non-standard low slope roof -- best way to insulate and ventilate?

I am trying to find a solution to properly insulate and ventilate an attic in my house. We purchased the house two years ago. The house had a history of ice dams. Before the first winter in the house, based on recommendation from the energy auditor, we had the house air sealed, added cellulose to the attic and additional vents in the roof (turtle vents) installed. Unfortunately, it did not help and with all the recent snow we are dealing with now (Boston area) there is another ice dam damage. The temp. in the attic is 40F when the outside temp is 20F.

Asked By Marcin Nowak | Feb 10 15
4 Answers

Heating/Cooling Degree Days

John Straube, in his book "High Performance Enclosures", indicates that for Heating Degree Days, in a high performance home, a base of 50 degrees (i.e. HDD50) should be used for computing annual energy use for heating. That reduces my average annual HDD65 of 4365 to HDD50 of 1838 in Louisville, KY.
Is there an equivalent high performance home base for Cooling Degree Days ?
Do you concur with Straube's assessment ?

Asked By Ted Cummings | Feb 20 15
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