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9 Answers

Trying to warm up an uninsulated concrete garage floor

Kenora Ontario Canada P9N0E7
Climate zone 7

Background- I have a 24 x 30 ft garage with 2x6 wood framed walls (R20 fiberglass batts in stud bays) and a raised heel truss attic (8 ft walls) the ceiling has R50 blown fiberglass.
The man door is located on the south wall and the two 7x9 insulated overhead doors are on the north wall...the ridge of the 6/12 pitched roof runs E-W.
The concrete pad is a 4 inch thickened edge slab over 6 inches of compacted stone; the earth is well drained and slopes away rapidly in all directions.
I use 1/2 the building for parking and 1/2 for a shop.

In General questions | Asked By Tim Brown | Feb 7 16
3 Answers

What makes ceiling fan remotes break?

About 10 years ago, somebody at the Florida Solar Energy Center was involved with the design of the Windward III ceiling fan, which at the time was the most efficient fan money could buy. Due I think to the variable blade pitch. I installed a couple of them and now one of their remotes no longer functions. What causes this and is it repairable?

In Green products and materials | Asked By Charles Campbell | Feb 3 16
16 Answers

Geothermal and SDHV in new ICF home

We are in the process of building a new home in Climate Zone 5. It is an ICF [insulated concrete form] construction from basement foundation to gable.

I am intending to use a SDHV [small duct, high velocity] system for forced air and heating in conjunction with a closed loop ground source heat pump.

What I am trying to understand is the impact to efficiency caused by my desire for SDHV on the heat pump options side of life.

In Mechanicals | Asked By Esteban Carlos | Feb 4 16
2 Answers

Basement remodel / Subfloor questions

I have a few questions about my plan to insulate a subfloor in the basement.

Let me provided the pertinent details and my purposed plan.

The brick ranch house located in zone 4a (Virginia) was built in 1965. It has both an above and below grade basement. The structure is concrete block. The front long wall and one short wall are completely below grade. The back wall and half of the other side wall are above grade. The basement is conditioned.

In Energy efficiency and durability | Asked By Steve Basic | Feb 3 16
1 Answer

Shingle roof over closed-cell foamed rafters

Martin - I'm the architect for a new house. The roof will be:

Wood shingles over
Horizontal strapping over
Vertical strapping over
Grace Ice and watershield over
Plywood sheathing over
Closed cell foam

Do you recommend this? Will there be trouble within the sheathing 'cause it's trapped between two non-breathing membranes: Grace Ice and Watershield (top) and closed cell foam (below)

Many thanks,

Louis Mackall
(you may remember me from Trident launchings in Groton!!)

In Green building techniques | Asked By Louis Mackall | Feb 8 16
0 Answers

Proper DHP sizing

So, I ran a Manual J calculation for a number of Portland, OR apartment units I'm renovating (2bdrm/1ba, ~750sqft each). All fall in the 12.5k-13.5kbtu range for heat load; closer to 9-11.5k for cooling loads depending on orientation. When I click over to the Manual S sizing calculator, it mentions Emergency loads of 10k minimum - 18k maximum. I'm not sure what exactly this means, and how it should affect sizing choice. Calc outputs are attached for reference.

In Mechanicals | Asked By jonathan nagar | Feb 8 16
2 Answers

Wall assembly

If a 4 or 6'' wall works good, what is wrong with a 12'' version of it?

In Green building techniques | Asked By Michael Abrams | Feb 8 16
1 Answer


I've been lurking here for awhile, doing what I could to make my home more efficient as money came in. As it was I've lowered my heating bills by about $850 a year before I started doing the more major stuff this year. Finally I had a home energy assessment performed, completed the suggested upgrades and then had the post retro-fit assessment completed just now.

ACH50 of 1.62 in an 11 year old house, and an EnerGuide rating of 85!

In Energy efficiency and durability | Asked By Calum Wilde | Feb 8 16
3 Answers

Wall assembly

I am building a new home in zone 6. I have a question regarding insulation in the window wells. I have 4 inches of xps externally. Of course I do not have insulation inside the window well area. That leaves the header area and a small amount around the window uninsulated. Should I use an internal insulation in the stud bays around this area? One window well is in a bathroom. Should a smart membrane be installed in this area?

In General questions | Asked By Charles Cloud | Feb 4 16
4 Answers

Insulating a 1890 balloon-frame Chicago house

I have a couple questions about my 1890 balloon-frame house.

It is a wood balloon frame house with 1" thick sheathing boards 8-10-12 inches wide. The original siding is a wood clap siding with a paper under it - later the house was covered in a type of tar paper and wire mesh to add a 1 1/2" cement stucco in a brick pattern (one piece shell) -- to give you an idea of outside make up.

I took off some plaster walls in my office to replace with drywall since they were starting to fall off and while those 2 walls are open I figured I would put some insulation in there before the drywall.

In General questions | Asked By David Post | Feb 4 16
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