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3 Answers

Insulate knee walls

Situation: Currently have knee walls with no insulation behind them or the cathedral portion of the ceiling. The rafters are 2x6's. Ventilation is provided from vents installed between the exposed rafter tails. Blown in insulation is currently blocking off the top of the cathedral portion. I live in zone 5.

In Energy efficiency and durability | Asked By Jim Johnston | Mar 28 14
1 Answer

Efficient roof hatch?

In a flat roof row house, I have a hatch similar to a commercial building to access my roof. There is no ceiling to speak of, save for a small crawlspace in the front. I will be insulating on the underside of the roof deck, thereby making the roof hatch an integral part of the insulated ceiling.

I have been surprised to find very little on the market in the way of an energy efficient, well insulated roof hatch.

In Energy efficiency and durability | Asked By Wayne Weikel | Mar 28 14
6 Answers

Flip the blower door?

How often are home *pressurization* tests done? The usual
blower-door run seems to be the "suck" test, looking for cold
air coming in, but it may not tell the whole story. Turning the
fan around seems to be a logical part of a "fog test", but one
doesn't necessarily want to blast fog juice all over an occupied
dwelling as even the most benign water-based formulations still
leave behind *some* sort of residue.

I'd opt for simply using warm air as my indicator. Tonight
I ran a "blow" test on my place, using my window-fan lashup

In Green building techniques | Asked By Hobbit _ | Mar 24 14
2 Answers

Window incentives / rebates?

Anyone know of any federal rebates or incentives for changing out old leaky windows for some new energy efficient windows?

In Green products and materials | Asked By Peter L | Mar 28 14
4 Answers

Best way to air seal an attic?

Just had a BPI Energy Audit and was told that they would use 1 inch of CC spray foam to air seal the attic floors and then blow in 15 inches of cellulose. Is this the best way to air seal and attic floor? Is it the most cost effective? There are ducts and an air handler in one attic space and just ducts in the other. The house is in Zone 4. Thank you.

In Energy efficiency and durability | Asked By Woody McMahon | Mar 27 14
4 Answers

Can someone tell me a few minisplit models that work exceptionally well in the colder climates?

Climate zone 6.
Approximately 1000 square foot area. Will be very well insulated. R40 floor, R60 or better roof, R30 walls with well detailed air sealing. Approx 76 sf of triple glazed windows.

The floor plan is very open, so I'm hoping one unit will be sufficient, with some electric baseboard supplemental heat in strategic areas.

This winter was horribly cold, with many days below zero, but I wouldn't call that the norm. The coldest day was approx -18 below for the low, and approx -8 below for the high.

In Mechanicals | Asked By Rick Van Handel | Mar 26 14
9 Answers

How much electricity do residential oil/propane heating systems draw?

I am on the energy committee in my town. (It's a volunteer committee that reports to the town government, promoting energy goodness to the municipality and residents.) Our committee recently was contacted by a resident in a rental home with a question about a mysterious spike in electric use.

In Mechanicals | Asked By Jonathan Teller-Elsberg | Mar 26 14
10 Answers

Can you quantify the air leakage savings of spray-foamed above-grade walls vs. batt insulated?

We are looking to convince a client that it's worth it to spray foam their exterior walls and basement. Does anyone have quantifiable data that shows the ACH@50 difference between two houses. One insulated with conventional batts, and another with sprayfoam?
Perhaps you've done air leakage tests on similar homes with the two different techniques?
Thanks.
Toby Smith

In Green products and materials | Asked By Toby Smith | Mar 26 14
23 Answers

Are operable windows an unnecessary extravagance in a today's green houses?

Just wondering if in today's climate controlled and mechanically ventilated houses if having windows that open defeat the purpose of meticulous consideration to air sealing and humidity control.

Are they strictly for luxury now? Ease of cleaning? Is there still a need to "air out" your house?

P.S. I do understand the need for a small number of egress windows for safety and building code requirements.

In Energy efficiency and durability | Asked By Rick Van Handel | Mar 21 14
1 Answer

How to retrofit the insulation of an existing basement slab?

What is the best way to insulate an existing walk out basement slab? When I bought the house I removed the wall to wall carpet and sanded and stained the slab. It is too cold to live with.

In General questions | Asked By anne edwards | Mar 27 14
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