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1 Answer

What method would be best for insulating the exterior of a foundation and still permit the application of stone veneer?

I am wanting to maintain thermal mass inside my envelope so I would like to insulate the exterior of my new foundation. I am considering mineral wool (rock wool) but am not sure about several issues of concern. I am hoping to use the compressed 3" batts for an R10 value but am unsure exactly how to apply.

FIRST: If I apply rock wool to the exterior of the foundation - how should that be done? Should I use some form of furring strip? What could I use that would withstand burial for 30 yrs.
SECOND: If applied on the exterior - what would the pros/cons for insects and termites?

In Green building techniques | Asked By Ralph Hertlein | Mar 30 14
3 Answers

Insulating the roof deck with both closed-cell and open-cell foam?

I am consulting on a home where the HO wants to have the insulation at the roof deck. They are thinking 2” of closed cell followed by 6” of open cell.

The HO put forward this idea.

2" closed cell at the roof first to provide the vapor barrier then followed by 6" of open cell which will be enough to encapsulate the top chord of the roof truss and minimize thermal conduction.

Does anyone have any experience with this type system?

Is there any concern of the two layers of foam de-bonding from one another?

In GBA Pro help | Asked By Mark Parlee | Mar 29 14
1 Answer

Old brick with closed-cell foam on interior - Exterior paint?

I have read a considerable amount about the challenges of insulating brick homes. As I am in an historic district, interior insulation is my only option. From what I have read, closed cell foam is my best bet.

My question is how to best handle bulk water on the exterior of the home. It is a rowhouse with zero overhangs. Presently the front of the house is painted and the rear is exposed brick.

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

Fireplace vs energy-efficiency

I'm striving for a net zero house in northern CA zone 11, which I think is a zone 3B on the US map. 6 inch blown cellulose walls with 1 " outside foam, R50 blown ceiling; mini-splits on each level. Here's the issue; my wife wants a fireplace for aesthetic reasons; I would prefer a wood stove with glass front as a supplemental heat source. . She's ok with an insert in the fireplace.
Is there technology that will make the insert a supplemental heater and not blow half my heat budget up the chimney when it's not on? Blowers to get more heat output? Your thoughts appreciated.

In Green building techniques | Asked By Michael McKinley | Jan 3 13
3 Answers

Improvement of older windows...

My son's home has a "great room" with lots of window area, including two double doors to a deck (one fixed glass panel and one door), rectangular windows above each door of nearly equal size (same width, slightly shorter), and two triangular windows at apex of ceiling/roof. These are 20+ year old standard thermopane wood windows of the time (seals appear to be intact).

In Energy efficiency and durability | Asked By Howard Gentler | Mar 24 14
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
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