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7 Answers

Exterior PLYWOOD; is it OK as is?

I just read a couple of lengthy posts here, dealing w/ exterior sheathing leading to condensation problems, and I am confused. Maybe I got lost as the conversation shifted among exterior foam and several slightly tangential posts. Very possible. My concern now is this: Should I drill holes in my exterior plywood, or rely on edge gaps and plywood's permeability to minimize or eliminate condensation?

In Energy efficiency and durability | Asked By jklingel | Feb 23 10
3 Answers

Horizontal skirt of XPS at footer; useless?

This statement "For the cases examined, horizontal skirt insulation (at the footer) has a negligible impact on the annual sensible heating load" comes from the Conclusion section of a report "Analysis of Basement Insulation Alternatives", by Ian Beausoleil-Morrison & Briana Paige Kemery, Mechanical & Aerospace Engineering, Carleton University, 1125 Colonel By Drive, Ottawa, ON, Canada K12 5B6. The "skirt" (typically, in Fairbanks, AK) is a two foot wide piece of XPS that is installed horizontally on the outside of the foundation wall, just above the a footer.

In Energy efficiency and durability | Asked By jklingel | Feb 24 10
1 Answer

What is the best way to insulate the floor above a dirt crawl space?

This is in a cold climate and the crawl space is unheated.

In General questions | Asked By Deborah Word | Feb 24 10
10 Answers

Renovating an old 1930's brick building. Need to find a way to make the building more environmentally friendly.

Adding insulation on the outside of the brick walls is not an option, as it is an old 1930's building which should be kept aesthetically how it is. I have thought about re-placing the roof. Budget is of course an issue, but any suggestions would be appreciated! Does anyone have any suggestions? Would love to hear them.

In Energy efficiency and durability | Asked By Ben | Feb 22 10
11 Answers

How much rigid foam insulation (polyiso) can be installed on the exterior of a building and still be able to install siding such as Hardiplank?

I am doing a whole house remodel/addition and am looking to maximize insulation without decreasing interior space, so would like to install as much as possible on the exterior and use spray foam in the 2x4 wall cavity.

In Green building techniques | Asked By Joshua Rogers | Feb 21 10
15 Answers

I have a new tight home and am advised to run my bathroom fan 4 to 6 hours a day

...to promote healthy air change and eliminate moisture. However, my interior humidity is 32% and I feel we need more to be comfortable. Is running the bathroom fan counterproductive by eliminating moisture? How do we determine "bad air"? If we don't run the fan the prescribed time we don't notice any difficultly breathing , congestion etc. Is it sufficient to run the forced hot air fan continuously to circulate humidity from showers etc. rather then exhausting the air?

In General questions | Asked By Dick Derby | Feb 22 10
4 Answers

Door R-values?

I can't find a whole lot of information about doors and their respective R-values. If I want to build a super-insulated home with good ventilation, what are some good choices for door materials and how should they be sealed?

In Green building techniques | Asked By Michael Schonlau | Feb 21 10
8 Answers

Temps under a slab

Does anyone have any links for the earth temperatures under a slab on grade, including under the footer and out a bit from the building? I've seen a very few that are close, and some isotherms w/out temps, but I'd like specific information geared to cold climates (14K dd) with 4" of XPS under the slab, ICF foundation walls, and with/without spacing between the under-slab insulation and the foundation wall. Kind of picky, I know, but that is what I need. Thanks. john

In Energy efficiency and durability | Asked By jklingel | Feb 20 10
19 Answers

Insulation on Exterior walls & Codes

OK... I've been reading 100s of responses using exterior rigid foam (from 1"-8") and then installing nailing strips for cladding, and all the gurus are going to this technique. May question is this allowed by code??? If I'm not mistaken, any cladding should be nailed to the stud at least 1". I understand that QC is a big component but when you have 1"-8" of rigid foam in between the nail strips and the stud and you are trying to "hit" the stud with a nail gun... well, I've seen the real world apps and I wouldn't bet my life on it.

In Green building techniques | Asked By Armando | Feb 13 10
0 Answers

Net Zero in Edmonton??

This is not a question but I am including a link to a very interesting blog that describes an attempt to build a net zero home in Canada's northernmost city. Over 10000 HDD... Hoping it might provide some good discussion topics...

In General questions | Asked By Garth Sproule | Feb 20 10
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