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11 Answers

When is an HRV necessary?

I'm building a ranch home in northern Idaho with a walk out basement. There will be some crawl space areas at one end of the house. I intend to seal them from the exterior so it is conditioned space. The main roof will have scissor trusses with spray foam under the roof deck so the space in the middle of the scissor trusses will also be a conditioned space.
Trying to get as airtight a house as possible, I would think that an HRV system will be highly recommended or even required. I am not very familiar with these systems.

In Energy efficiency and durability | Asked By James Mills | Feb 28 14
2 Answers

Choice of rigid exterior roof insulation

The February 2014 issue of the Journal of Light Construction has an article starting on page 41 titled "Insulating Cathedral Ceilings." On page 46, the second paragraph under "Rigid Foam Above Sheathing," there first is mention of polyisocyanurate and XPS rigid board as options for this purpose.

In General questions | Asked By Dick Russell | Mar 1 14
2 Answers

The Breathing Window

Anyone familiar with/comment on the Breathing Window? Is it on the market?

Here is what they say:

"...the Breathing Window reduces ventilation running and heat-loss costs by 10kWh/m2.annum..."
This means comparative costs with other models and types of HRV's.

" 95% lower running costs than always on ducted HRV.
50% lower ventilation heat losses than ducted HRV, only occupied areas are ventilated.
4 year payback compared with 40 years for a ducted system.



In General questions | Asked By fitch plate | Mar 3 14
0 Answers

Recommendations for a quality, low-U, high-SHGC sliding or tilt-and-slide door?

I've found some great info on this site as usual; here is one example: http://www.greenbuildingadvisor.com/blogs/dept/musings/all-about-glazing...

I'd prefer fiberglass but am also considering a uPVC frame. Does anyone have experience with a tilt and slide door in terms of durability?

In Green products and materials | Asked By Brent Mellen | Mar 3 14
3 Answers

Proper flashing placement?

My foundation sticks out past a wood framed wall, osb with taped seams, housewrap taped seams, 4" of polyfoam, lower 12" of wall has self stick membrane that completely covers foundation. I am getting ready to put up strapping and wood siding but noticed there is no flashing at bottom of wall. do I have to remove the foam and flash the entire wall to edge of foundation or can I put the flashing between foam and strapping, using sealer and tape on the foam to flashing edge .the distance from wall to edge of foundation is approx. 8", so even with foam and siding I still have approx.

In General questions | Asked By darren williams | Mar 3 14
11 Answers

Need help reducing energy costs

I have a ranch home in climate zone 5a (Northern NJ). It's a ranch, with a partially finished attic, approximately 1600sqft. Primary heat source is propane via hot water baseboard, with a gas insert fireplace, and electric baseboard in the attic. This is my first year in the house, so I don't have historical data, but this year we've been averaging approximately 300 gallons of propane use per 5-6 weeks, which is quite expensive!.

In General questions | Asked By Eric Barker | Feb 26 14
3 Answers

Correct all-year-round ventilation for basement (bedroom, kitchenette, bath, laundry) in cold climates (Zone 5)

- I live in Worcester County in Massachusetts (Zone 5)
- The basement comprises of a finshed section that is an open area which serves as a bedroom for my mother-in-law, and an unfinished section that is the laundry room and storage (Total basement size is 930 sqft). See attached document for floor plan and ventilation plan.
- We are adding a bathroom and kitchenette by taking a bit of each section

In Green building techniques | Asked By George O | Mar 3 14
5 Answers

Should we buy products from China?

ABC did a news piece on the pollution in China. I have thought of this before but it is fresh in the news.

China makes cheap solar panels, but how much of that has to do with the lack of environmental regulations? If we care about the environment, should we buy products that just ship the environmental impact to a foreign land?

In General questions | Asked By Robert Hronek | Feb 26 14
3 Answers

Insulating an older masonry building inside above grade and below

This building is located in the upper peninsula of Michigan. It is a church of about 40 people, with limited resourses. It has been heated with an oil furnace since it was built in 1955. The furnace has failed this winter, and they want to switch to propane. Our church is in the lower part of Michigan and our men's group is willing to go up and do the work of insulating and drywalling the interior walls of this building, with all labor donated.

In General questions | Asked By Darwin Thompson | Mar 2 14
1 Answer

HRV / ERV for a conditioned crawlspace

I'm in climate zone 5-6. 3' conditioned crawlspace, with 12mil. plastic sealed floor & closed cell spray foam insulation installed on crawlspace walls & rim joists. Forced air gas furnace- ducts into crawlspace with one small flapper vent allowing some air into crawlspace when furnace/ ac is running. I currently run a dehumidifier about 12-24 hours a week in summer months to maintain a humidity level consistent with main floor. I'm about to seal the main level with new windows and 3" of polyso around exterior, and thus also want to install an HRV/ERV.

In General questions | Asked By stu m | Mar 2 14
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