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53 Answers

I am in the planning phase of building a home in the NJ-NY area, Climate zone 5. As I investigate my options; SIPS, double wall stick 2x4 wood, 2x6 wood, ICFs, CMU, Larsen trusses, etc.. and the myriad of permutations to insulate each one (spray foam, cellulose, hybrid batt & flash, exterior rigid foam/iso panels, etc....) I came across STEEL. My goal is as high R-value as I can get within reason $$, with hope of upwards of R-30 final values. That said, I need some objective input.

Asked By Sal Lombardo | Dec 27 12
4 Answers

I am building a new house which will be clad in full-thickness natural stone veneer. A stoop slab just outside the front door will be poured on top of a cold room that's part of the foundation.

My concrete contractor, of course, wants to pour the slab right against the rim joist. That's not going to happen. But what SHOULD happen?

With the masonry veneer, the wall above includes a 1" air space--should I have the guy leave the 1" also between the slab and the rim? How would I ensure proper water drainage out of that space?

Asked By Andy Chappell-Dick | May 18 13
14 Answers

I am working with a local energy efficiency contractor. They are replacing my old roof (which badly needs replacing) with a new roof. They will be spraying five or so inches of closed cell foam directly against the decking. This will fully seal my attic. My question is, how does this work if you do not have air conditioning in the house, other than window units in the bedrooms and one in the living room.

Asked By Rob Graff | May 7 13
4 Answers

If I have walls and/or an unvented cathedral ceiling that are insulated with closed-cell spray foam from the inside, can I also have rigid foam on the outside of the sheathing to limit bridging?
Just wondering if it's somehow a bad idea to have the sheathing sandwiched between two layers of foam.

Thanks, Chris.
(This is for Ottawa, Canada, equivalent to zone 6A.)

Asked By Christopher Solar | May 13 13
3 Answers

I'm getting quotes from contractors right now to insulate a small cottage with an unvented cathedral ceiling using 2x10s. I'm in zone 3C.

One contractor has suggested spraying 5.5" of open-cell foam between the rafters and calling it a day. I asked if we could just fill the entire 9.5" cavity and he said, "You achieve maximum efficiency @5.5. Any more is overkill. It will expand a couple more inches as we will not cut it but leave the excess."

Code requires R-30 for ceilings around here.

I may be wrong but doesn't more insulation mean higher R-value?

Asked By Nicholas Jensen | May 13 13
6 Answers

We are building our first SIP house complete with SIP foundation. We will be using Hardiplank siding which requires 6" clearance between the lowest plank and grade.

So for those 6" or so the skin of the panels will be exposed, and in certain areas it may not be the foundation panels which will have the pressure treated plywood, etc.

So this general question is: What should I do with that space? Normally this space is just exposed poured concrete walls, but with a SIP building, what do you do?

Asked By Joe Hartwig | May 7 13
7 Answers

We are building a new home soon and I really want to include a small cold cellar to age a few beers and keep some wine cool in lieu of a beverage refrigerator. I also want keep our chest freezer (we buy full animals to process) in here to lower its run time.

Asked By Troy Stevenson | May 7 13
4 Answers

We are using 2" of exterior polyiso foam with air-barrier established at the Zip sheathing. Our first choice in regards to the basement rim joist was to use closed-cell spray foam. Now I understand that we should avoid this "foam sandwich" but open-cell is an option due to its vapor permeability properties. Then I read more about foam and am a bit afraid of spray foam in general.

Asked By Troy Stevenson | May 4 13
4 Answers

Part of my retrofit included a standing-seam metal roof, the type
with snap-together panels. I've read some of the folks' prior
experiences with metal roofs and snow, and spent some of my first
winter watching the big cornices slowly form over the edge and
then thud down -- in the back of the house, onto the basement
bulkhead and outer edge of the little matching rooflet over the
heat pump [and boy, am I glad I constructed *that* to be strong],
and shoveled most of what fell farther away from the house so it
wouldn't form a huge mound and then melt toward the basement wall

Asked By Hobbit _ | May 2 13
1 Answer

We are wondering if it is wise to plaster directly on the 2" mortar that protects the straw bales or if we should use furring and plywood on which we would fix a screen to put the plaster on. It would add an air gap between so that the wall could dry better but we don't know if it is worth it.

What do the experts think?

Asked By Serge Bedard | May 1 13
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