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4 Answers

EPS exterior with CC SPF Interior


I am currently pricing out insulation solutions to achieve between R-35 and R-40 for my above grade walls.I am in climate zone 8. I have priced out adding 2 inches of CC spray foam then filling the cavities with fiberglass batts. This also included 0.5 inches of XPS outside to cut thermal bridging. However reviewing that I realize that is creating a sandwich with no path for the moisture to exit. I am still wanting to combat the thermal bridging concern. One spray foam company recommends going to 3 inches to ensure no condensation forms between the batts and the foam.

Asked By Canadarox12 | Apr 2 18
9 Answers

ERV - combined one or two vs independent one or two?

Building a reverse 1.5 with walkout basement. 2300 sq ft finished on main level and 2000 finished on lower level. Looking at two conventional HVAC systems. If we go with ERV intergrated with air handlers, presumably need two ERVs. If we go with an independent duct ERV system, do we need two ERVs duct systems or will one independent ERV duct system work for the whole house? Which system makes the most sense? Thanks.

Asked By Bruce Davis | Mar 27 18
7 Answers

Stucco drainage wrap over exterior Roxul

Does anyone have installation details for a stucco drainage plane product that can be installed over rigid insulation? An example product is Boral drain n dry, but I can’t find details for a rigid foam install.

The alternate install would be 1x4 vertical furring strips over the Roxul, then paper backed lathe over that for stucco base.

Asked By Phil Boutelle | Mar 25 18
23 Answers

ZIP, AdvanTech, OSB, and Plywood.

ZIP, AdvanTech, OSB, and Plywood
What are people’s preferences/experiences when it comes to these products in the two following locations?

Roof Sheathing – Vented attic, with metal standing seam over top. Also what underlayment would you use with each?

Wall Sheathing- Inside to out lay-up is ½” drywall (hopefully fairly airtight) (possibly a membrane required by building inspector), 2”x4” studs, ½”sheathing taped (3M) (air barrier), 2 layers of 3” used fiberglass faced polyiso (6” total) Tyvek (WRB), horizontal ¾” furring strips, vinyl board batten siding.

Asked By Dave B | Mar 14 18
1 Answer

What happened to....

I was thumbing through a magazine this weekend and saw an ad for a heat pump add-on for an existing electric water heater, fiberglass coated building panels for basements, 2 part foam, lot of hot water solar designs, indoor air quality concerns, $1 a watt solar panels in production from RCA, some interviews with a builder who was on the road to net zero, high ozone depleting building material list with xps on it, and many many more interesting concepts, ideas, plans, interviews from people that actually had this stuff going as well as some real crooked news bits involving oil companies and uti

Asked By T Carlson | Mar 26 18
8 Answers

Insulating Unvented Cathedral Ceiling

My wife and I are designing and building a home in Western Washington (I'm a professional structural engineer). One of the spaces is a great room with a cathedral ceiling featuring exposed trusses. Due to the configuration of the roof (specifically, an adjacent roof with a perpendicular ridge that eliminates the possibility of eave vents for approximately 3/4 of one side of the roof), I'm leaning toward an unvented assembly. I would have preferred venting it, but I don't think the configuration of the roof will allow it.

Asked By jptorny | Mar 25 18
6 Answers

Bringing down the cost of PERSIST construction

I really like the idea of PERSIST houses. Keeping insulation on the exterior makes a lot of sense, and there are few more foolproof methods to build a strong air barrier. But the undeniable drawback to PERSIST construction is cost. Peel and stick membranes are significantly more expensive than standard housewrap, and there is a lot of OSB sheathing involved. REMOTE constructions address some of these concerns, though really only work with unconditioned attic spaces. I was trying to think of ways to bring down cost and reduce material use, and I had an idea I wanted feedback on.

Asked By Aedi | May 12 17
5 Answers

Polyiso Interior Insulation in Old Barn

I am starting on the second floor remodel of a 19th c. barn, and I'm considering using polyiso panels on the interior side. I've never used rigid and non-rigid insulation in conjunction, and I have a few questions.

The Basics:

This will be a storage space and workroom. The barn is in Maine. The barn exterior is original horizontal siding (which I may be replacing but not until summer) over original vertical 1x sheathing (with some gaps). This is attached directly to the frame of the barn, which is open on the inside and roughly 5" deep.

My Plan:

Asked By ThreeBirdFarm | Mar 22 18
7 Answers

slumping of siding from nailing through rigid foam

Thanks for any assistance you can provide.

I am wanting to add additional insulation on the outside of our home. We are in zone 6. Our current walls are 2x6, 24 inch on center with 6 inches of fiberglass insulation, 7/16th OSB with tyvek. We have lived with cedar siding for 30 years and are now wanting to remove the siding and windows. Replace the windows and us LP siding.

Asked By user-7005676 | Mar 20 18
5 Answers

No basement, want no interior VOCs, looking for low cost exterior climate control for paints, caulking and their ilk

I have nearly finished construction of our slab-on-grade house in zone 5 MA.

We have neither a basement, an attic nor garage. All the interior space shares the same air, with a tiny utility room. Interior air quality is important -- the house is all pine and cement. No plywood, no mdf, no chipboard, no OSB; essentially, no glues or resins. No combustion equipment .. all electric. Very few plastics, no carpets, no paint. What we breathe matters.

Asked By Kenneth Gartner | Mar 23 18
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