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7 Answers

Insulation and barriers on inside of a double brick wall

I am in Toronto Canada doing reno work and have stripped the walls in a few rooms down to the (double layer) brick wall. I am puzzling over what air and moisture barriers combined with insulation would be best. I don't want to loose too much space. 2X4 wall thickness or possibly up to 2x6.
Can I have foam sprayed directly on inside of brick ?
Or, more conventional , a layer of tar paper nailed to brick(or should I fur this first?), then a wood framed wall insulated insulated.

In General questions | Asked By Richard Clark | Apr 5 12
1 Answer

Staggered studs on 2x8 plates....anyone do it?

There is a lot of talk here about OVE framing, double stud wall framing and various types of thick exterior foam options. However I have not found much talk at all about staggered 2x4s on 2x8 plates. I realize this does not eliminate thermal bridging at the sills and heads of the walls, but I would have to assume it would create a slightly stiffer wall too. 2 rows of 2x4s cost about the same as a single 2x8 around here. The 2x4s would be on 12" staggers, so a 24" o.c. on their respective sides.

In General questions | Asked By Jesse Lizer | Apr 23 12
3 Answers

Two-story home on slab vs. one-story with basement


I'm looking at building a Passive House (or close to it) in Pennsylvania. My kids are teens, so I had considered building a 1-story home and put the kids' bedrooms in a finished basement. I had also considered a boxy 2-story on a slab.

Both arrangements have their pros and cons in terms to materials required (the cost of basement walls vs. more framing/siding/windows, etc.). I don't think a lack of daylighting will be an issue since my kids are only in their rooms to sleep. Anyone have an opinion on the matter?

Thanks in advance!


In PassivHaus | Asked By Jason Kibbe | Apr 16 12
1 Answer

Air sealing effects

I have a very leaky home and am contemplating having air sealing done as well as some improvements to the insulation. While I know this will help improve energy efficiency, I was wondering a couple of things:

1) Once the air sealing is complete and the house is tighter, will indoor air quality be affected? That is, less air exchanges with the outside. If so, should I look at installing mechanical ventilation (i.e. HRV, ERV)?

In Energy efficiency and durability | Asked By Ellyn Daniel | Apr 17 12
7 Answers

Insulation for vehicles - if not Reflectix, then what?

Much thanks to everyone here for the great comments on Reflectix on the other Q&As. I'm glad I read them before I bought any!

But now I am stumped. This is one of the main recommendations on the RV-builder forums for insulating a vehicle to avoid condensation and keep warm/cool.

I am preparing a Chevy Express cargo van for research work (using it as office/sleeping area). It has a steel skin, and hollow steel "studs" spaced about 2 feet apart, about 3" deep between. Ceiling is similar. Also, there are voids in those "studs" and in the door recesses. (http://bit.ly/HRnArM for a pic).

In Green products and materials | Asked By Dylan Gordon | Apr 17 12
4 Answers

Insulating and sealing off the underside of pier built structures?

I am planning a kitchen addition to be built on concrete piers....to eliminate the cost and effort of perimeter footings and crawl space walls. The floor would be built using I-joists and I would install (2) layers of 2" rigid foam down into the joist bays so that the panels sit on the lip of the I-joist flange. I would also seal the panels with spray foam around their entire perimeter within each joist bay. Is this insulation concept acceptable? Does some other material/barrier need to be installed on the bottom of the joists to keep out pests or animals and/or moisture?

In Energy efficiency and durability | Asked By JONATHAN SCHOLL | Apr 18 12
3 Answers

Foam board insulation install

I am not in the building trades so I am seeking some help and advice from the pros.

I contracted to have new vinyl siding applied to my existing home in the Detroit area which included foam board insulation underneath. The crew removed the old aluminum siding and the trim caps around the existing vinyl windows. They applied 3/4in. foam board to the work area and siding channels around the effected windows and corners. This was followed by the new vinyl siding and aluminum trim and gutters.

In General questions | Asked By Zeno Potas | Apr 18 12
4 Answers

Summer seasonal home construction and codes


In GBA Pro help | Asked By Leslie Guerci | Apr 17 12
1 Answer

What is the total percent of heat loss by conduction?

In relation to convection, radiation.

In PassivHaus | Asked By Lorene Walvatne | Apr 22 12
15 Answers

How to build a cathedral ceiling

I just read how to build a cathedral ceiling and the voluminous responses.
I am a homeowner. We are about to have a shed dormer built with minimal roof slope and ceiling height.

I plan to push for the GBA detail for cathedral ceiling with emphasis on air sealing 6 sides of the f/g insulation.
Do I understand that the accuvent also must be caulked or sealed?

In GBA Pro help | Asked By Dave Nicholson | Mar 29 12
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