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1 Answer

Martin, How about this option?

Thank you for the advice. What about just using it [double-bubble foil] at the ceiling level as this will give me an opportunity to better air seal the cathedral ceiling? Furring out the ceiling will give me an air space that should help radiate heat back into the envelope. Otherwise I will have a hard time air sealing from above, along with the fact that there's a full width porch across the front that needs to be vented out the ridge.

In Energy efficiency and durability | Asked By Bob Spontak | Aug 22 13
3 Answers

I have access to some inexpensive double-bubble foil insulation

I'm building a home with cathedral ceilings 8/12 pitch exterior, 6/12 pitch interior. Thinking of using the foil as a radiant barrier at the bottom of the top cord of the truss. This will create a baffle to vent roof . Then using the foil bubble wrap in the interior of the bottom cord of truss then use furring strips to create an air space then drywall. Then fill void in truss webbing with blown cellulose.

Will using vapor barriers in this configuration cause any problems? House to be build in zone 4 Tennessee.

In Energy efficiency and durability | Asked By Bob Spontak | Aug 21 13
37 Answers

Waterproofing contractor has other ideas

My plans called for placing the foundation drain pipe next to the footer. This is a non-standard practice in my area and required digging and pouring a thicker 12 inch footer instead of the typical 8 inch footer used in these parts.

Now, the waterproofing contractor is refusing to place the drain line next to the footer. Several years ago he switched to placing the drain (a rectangular pipe) on top of the footer and thinks this is the better method.

In Green building techniques | Asked By Steven Knapp | Aug 7 13
3 Answers

1" Polyiso *without* foil facing??

It's time to reside my 1960 brick front ranch near Rochester, NY, zone 5 moist (according to NY energy code or zone 6a if you prefer to believe the USDA.

The lot is next to woods, a creek and a bog.

In Energy efficiency and durability | Asked By J Heckmann | Jun 30 13
2 Answers

Can I know the function and operation of duct heating on two channel method?

The specific and simplest explanation for the duct heating on two channel method..if can, hope can have the picture..Thank you

In Mechanicals | Asked By HO Y NAM | Aug 21 13
4 Answers

Our indoor humidity is 65-70% consistently, dips to mid 40s in the winter. Why so high?

I've got an indoor humidity question. The house is about a year old, 1700 s.f. with a final blower door of 90 cfm50. We've got a Venmar Eko1.5 ERV and minisplits.

Outside humidity doesn't seem to matter, inside humidity remains fairly high. Our indoor humidity is 65-70% consistently, dips to mid 40s in the winter. There's none of the obvious moisture makers and no sign of leaks. It's almost like the ERV "multiplies" the moisture. My original understanding of the ERV was it was going to help lower the humidity? Any Ideas would be appreciated.

In General questions | Asked By DREW LAPERLE | Aug 20 13
3 Answers

Insulating a 1960's house with no room in wall for insulation

I have recently bought a house in south-eastern PA. The first floor exterior walls are brick & block (4" cinder block). I took down wood panelling in the family room and found that there was no dry-wall behind the panelling on the exterior walls. In addition to this, there is no insulation or room for insulation. After the cinder-block, there is about 1/2-inch of space and a thin foil vapor-barrier. I'm at a lose as to how to insulate this room properly without losing precious interior space.

In Energy efficiency and durability | Asked By Drew Jacobs | Aug 21 13
4 Answers

Concerns with an energy upgrade on an old home envelope

I'm planning on residing 3/4 of my house. I will also be installing high density cellulose, and 1.5" of foam under the new siding. I live in Upstate, NY.

I installed a high efficiency boiler with on demand hot water, in 2010. At that time my blower door test stated that my house was pretty tight. I feel I will probably need a source of supply air. If it could also supply air conditioning in the summer it would be great.

In Green building techniques | Asked By John H. Dennis | Aug 20 13
3 Answers

What is the best moisture barrier to use on a basement ceiling?

We own a 1903 cottage in a mountainous, wet (zone 6) area of Central Pennsylvania and have a major moisture problem. Half the basement has a dug out red clay floor and other half has a concrete basement. The cottage is surrounded by trees and doesn't get a lot of direct sun. Our cottage is like a sponge... a constant battle with mold and mildew! We are looking into a home dehumidifier system, redirecting the rain fall and finishing off the red clay flooring. ( we have heavy duty plastic down now - helps)

In Green products and materials | Asked By Elizabeth Hummer | Aug 20 13
3 Answers

Any advice for installing skylights in an unvented cathedral ceiling, other than don't do it?

Hi I'm getting set to install 2 velux skylights in the roof of my addition. Its a shed roof style addition that I built using 2x 12 rafters that will be dense packed with cellulose and on top of that I have a SIP of 2 layers of 5/8 advantec sheathing and 2 layers of 1.5" blue foam.

In General questions | Asked By chris steiner | Aug 17 13
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