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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
9 Answers

Can interior basement insulation cause moisture damage to my sill plate or frost damage to my stone/concrete foundation wall?

Sources of technical information I have read on this are:
1. Retrofitting Basement Insulation, By Martin Holladay Issue 236 - June/July 2013
2. How to Insulate a Basement Wall, Posted on June 29 2012 by Martin Holladay, GBA Advisor
3. Hybrid Foundation Insulation Retrofits: Measure Guideline Building America Report – 1108, 13 January 2012 (Rev. 4/12), Joseph Lstiburek and Kohta Ueno

In Energy efficiency and durability | Asked By Charles Galgowski | Oct 10 16
14 Answers

Slab and foundation insulation for partially earth-bermed home

Hello GBA forum members! First post here.

We are building a slab-on-grade, two-story home that will have concrete walls on the north and west side of the 1st level. These sides will be earth-bermed and the south and east sides will be framed (sort of like a walkout basement). We will be putting PEX in the slab. We are in Wisconsin.

I am unsure of where to insulate the concrete. I want to try and keep all of it within the envelope.

Please see attached image.

In Green building techniques | Asked By Kevin Wright | Oct 11 16
8 Answers

SIP construction with Roxul on interior service cavity wall

I am new to the forum, but have been here a while reading allot of very informative posts. This seems like a great community to find like minded experts who are passionate about building environmentally friendly homes.

In Green building techniques | Asked By Rob Andrushko | Oct 11 16
15 Answers

Retrofit HVAC installation in Zone 6a

Our house is a bungalow (1200 sqft) with a 600 sq ft split addition near Toronto, Canada ~ 6A. It is reasonably tight (spray foam throughout).

Our HVAC Retrofit will include replacing an old oil boiler with a NG appliance and installing a ventilation and AC system. When making decisions about this retrofit, IAQ is our most important criteria, followed by operating cost. My wife has a few health issues that make IAQ very important to us.

The two systems I am considering are:

In Mechanicals | Asked By Joe McRae | Oct 7 16
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