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2 Answers

Internal wall of a 1835 house


I live in a greek revival house built in 1835 on Cape Cod (MA). Over the years this house has gone through different renovations/updates some more successful than others. We are in the process of renovating the top floor which still has original wood windows (in really bad shape unfortunately) and no insulation.

The house uses post and beam construction (I was told) and the side walls (East and West facing) don't have any cavity. The North and South walls (front and back of the house) do have cavities and have been insulated with cellulose 3 years ago.

In Energy efficiency and durability | Asked By Riccardo La Rosa | Oct 14 16
2 Answers

Are minisplit refrigerant lines better in a wall or outside?

Will the heating efficiency of a mini split operating in a cold climate be effected by whether the refrigerant lines are run inside the walls and kept warmer vs running them down a chase on the outside?


In Mechanicals | Asked By Michael Prisco | Oct 14 16
1 Answer

Should standing seam metal roofing be vented over a roof insulated with exterior rigid foam?


This question is related to another question ("Is it advisable to use nail base insulation panels over a roof insulated with closed cell spray foam?") that I asked over a year ago, but for some reason when I try to post to the original thread I get blocked......

In Energy efficiency and durability | Asked By Jodi Gunderson | Oct 14 16
9 Answers

Best way to insulate for staple-up radiant heat?


In Mechanicals | Asked By Jack Roberts | Oct 13 16
8 Answers

Cooling a west-facing house in an equatorial climate

Hi All,

I am currently living in Kuala Lumpur, Malaysia. Malaysia has an equatorial climate that has a high of 93 °F and a low of 77 °F. The early evenings are usually 84 °F tapering off to 80 °F at midnight.

The house is very hot especially the top floor where the bedrooms are situated. It is quite usual for the top floor to remain at 89 °F throughout the night.

My house is 2.5 storeys and faces west with a lot of windows. I have tinted these windows with solar film. I cannot shade the house as I do not own the land beside it.

In General questions | Asked By Luke Wood | Oct 5 16
3 Answers

Best method for insulating

Doing foundation work for a new house in Jackson, Wyoming it is in Climate zone 7B. The architect has specd. 2" closed cell foam then r13 and 1/2 rigid foam over sheathing (exterior).
Based on current Building science knowledge, I don't this is a good idea.
any thoughts on the best method of insulation for this project would be greatly appreciated.

In Energy efficiency and durability | Asked By Donny Sanders | Oct 13 16
3 Answers

Minisplit compressor

Hey all, I installed a Fujitsu compact cassette in summer and with the weather getting cold it has started to run its heating cycle. I've noticed that the outdoor compressor generates a large amount of water in heat mode. Specifically it is able to fill up a 5 gallon bucket in slightly more then a day. I know during extreme cold it can cause ice to form and then melt out the bottom. But is it normal to constantly have water coming out of the outdoor compressor even during mid 40s weather? Can't find anything in the manual.

In Mechanicals | Asked By Chris King | Oct 12 16
1 Answer

Exterior foam substitute above thermal envelope on attic wall


I'm planning 4" of exterior rigid foam on my walls with a cellulose insulated attic floor. My WRB is outside my rigid foam. Because design uses a monoslope roof, there's a large portion of attic wall that's above the thermal envelope of the house. In this area, are there any good assemblies that I can substitute for the rigid foam? My hope would be to reduce labor and use less foam.


In Green building techniques | Asked By John Ranson | Oct 13 16
2 Answers

Wanted: vapor barrier coating for existing basement floor

I've read a lot recently (mostly here) on vapor barriers, vapor retarders, and vapor diffusion, and eventually my eyes glazed over.
One take-away was that vapor barriers DO matter for basement floors.
My brother is buying an old brick house in zone 5. The concrete floor has been patched in a few places, but is in good condition. The seller has a dehumidifier running, and admits that it smells musty sometimes- like after a rain- if the dehumidifier isn't running.

In Green products and materials | Asked By Ben Rush | Oct 13 16
11 Answers

Who has a favorite heat-pump water heater?

We are now underway with our "pretty good" house here in southern Oregon and I am committed to the hybrid heat pump water heater concept for our 2100 sq ft, three generation house. With four adults and a grandchild in the house, I felt that an 80 gallon unit would be desirable. We plan to locate the HPWH in a centrally located laundry room which is just under 700 cubic feet and have plumbed a floor drain into that room for condensate or tank failure (hope NOT). I had been inclined to go with the GE GeoSpring but I have heard a rumor that GE is going to discontinue manufacture.

In Green products and materials | Asked By Alan Hart-McArthur | Oct 13 16
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