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6 Answers

Slab insulation

I need to insulate a slab and usually use rigid foam. However this project is a woody area and there are lots of termites nearby and I know they love foam. Is Roxul drainboard or rock wool a good option in this case?

Asked By James Haug | May 25 16
19 Answers

HVAC - Gas vs heat pump vs ducted mini split

It seems the general consensus here, on a very tight or "pretty good" house, is for ductless minisplit. I'm trying to understand the economics.

The following parameters are non-negotiable:
1. Climate zone 3A
2. The house will be piped for natural gas for, at a minimum, cooking and outside grill

Asked By c l | May 22 16
2 Answers

Condensation in roof rafters in a metal framed house?

Hi, I am trying to build a metal framed house in Bonsall CA, climate zone 10 in California, climate zone 3 nationally. 13 miles inland from the Ocean about 40 miles north of San Diego. One half the roof will be metal trusses, the other half will be conventionally stacked using 2" x 10" metal rafters. On top of rafters is radiant barrier plywood, 40# felt, followed by Spanish Clay Tiles with O'Hagin vents.

Asked By Peter Coz | May 25 16
4 Answers

Which wall system is appropriate: ICF or double-stud 2x10 with full height veneer stone?

I have a client who wants a thick wall construction with full height veneer stone that comes "right out the ground", so there is no typical foundation to siding detail. This is in zone 5 Canada and I am concerned about building a wood framed wall because I can't really seem to come up with a good detail to vent the cavity I think I need to install behind the stone. Any ideas out there? I am thinking icf is the best way to go but I am open to suggestions.

Asked By Marty Munroe | May 21 16
19 Answers

Why is our home so inefficient?

We bought an 1,800 sq. foot house in the north Berkeley hills in November of last year. There was a small mold issue which we remediated in December and January. During that time we also did an extensive HVAC upgrade, with a 3-zone heating/cooling system, smaller/more efficient duct work, an in-line dehumidifier, and in-line air filter. (Our daughter is sensitive to mold and other airborne allergens, which is why we installed the dehumidifier and air filter.)

Asked By Chris Durand | May 22 16
4 Answers

Exterior foam and residing...with Roxul?

This is a follow up to an earlier post, from which I got great input, but I think this alternative idea needed another post. After reading about Roxul (and not yet being locked into anything about my previous plan), I wondered if this scenario would be workable, and/or what problems might be most in play.

Asked By Howard Gentler | May 20 16
2 Answers

Missing kickout flashing

I don't have kickout flashing on any of my wall/roof intersections. In fact, I've never actually seen a house in my area that has kickout flashing. My house does have the last (or I guess the first) piece of step flashing sticking out in front of the siding. The area I'm most concerned about has a downspout emptying just above the wall. I think I should extend it further so it doesn't dump right along the wall.

Asked By Michael Geoghegan | May 20 16
3 Answers

Use of polyiso below a slab

In CZ-4, I will be building a Net Zero slab-on-grade ranch, on a flat lot, on top of a ridge. All water drains away from the site. The slab itself will be raised about 2 feet above the current grade level. Under the slab will be a sheet of poly, 2" of sub-slab insulation, and about about 18" of gravel, all above the current grade level. There will also be 3½' Overhangs. Foundation drains will drain to air.

Asked By Ted Cummings | May 16 16
7 Answers

How to choose an electric water heater?

I'm looking for an electric hot water heater that is efficient and not too expensive. Not interested in heat pump type, just basic efficient model. The two suppliers we deal with use American or AO Smith. Any thoughts on these? Any other brands? Thanks, Ben

Asked By Ben Williams | May 19 16
24 Answers

Exterior rigid foam and re-siding project

I'm seeking input and opinion. I'm looking to re-side with the dread vinyl (need the low maintenance for my two story house). My 40 year old post and bean house has interior sheetrock, 3.5" of fiberglass batt insulation with kraft paper, rough cut full 2x4 studs on 24" centers, plywood sheathing (I think 5/8"), paper (a mix of Tyvek and felt), and cedar shingles. Shingles and paper will of course be removed, sheathing inspected in the process. I'm in zone 6.

Asked By Howard Gentler | May 2 16
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