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3 Answers

Furring Strips on Rock Wool + 4 Stories = Plumb Cladding?

Based upon much research including John Straube's "High Performance Enclosures" figure 4.11 I am interested in using rock wool insulation to the exterior of my exterior walls in an upcoming four story multi-family structure in Maryland (Zone 4).

So the sandwich from out to in would be:

Horizontal Cladding (Vinyl or hardie)
1x4 vertical furring strips
1.5" Roxul ComfortBoard IS
WRB - Tremco EnviroDri Fluid Applied
2x6 16" OC (lilkely insulated with Fiberglass Batt)

In Green building techniques | Asked By Shane Pollin | Dec 2 13
2 Answers

New home: wall design help please

Ok, so we probably should have worked out the details on this sooner, but here goes....

In Plans Review | Asked By Dave Morgan | Dec 3 13
12 Answers

Remodel-Zone 4a

I am working on a 1300sq ft remodel in zone 4a (Baltimore). The home is a ranch, on a sloped site, with a basement that walks out to grade in the rear. Original construction is 2x4 framed walls and gable roof with board sheathing. I plan to do a full gut remodel. Strategy for air sealing and insulation is my main concern.

In Energy efficiency and durability | Asked By Charles Chiampou | Nov 26 13
6 Answers

Using Reclaimed Fiberglass Faced Polyiso....another question

Based on advice from Dana Dorsett and Martin Holladay we decided a good wall assembly for using my reclaimed roofing iso in zone 5A was as follows
- drywall
- 2x6 with rock wool
- OSB (substituted for ZIP)
- 3.5" reclaimed iso
- 1" EPS
- housewrap

I talked this over with my builder and he had a few concerns.

First is the location of the flashing. With part of the cladding being EIFS, he stated that the EIFS installers will flash on top of the iso, then put on the EPS and then apply the EIFS to that. So he suggested we locate the housewrap between the polyiso and the EPS.

In General questions | Asked By Robert Kohaus | Nov 26 13
3 Answers

Rubber roof in winter -- help with installation

Ok..I have a deck over conditioned space on my project. I was hoping for a warm enough day to install the roof but we haven't had the weather break and I fear it won't happen until spring. The roof is 1/12 and 3/4" plywood and all new and there is a roof above the deck that is currently supported by long 2x4's to the earth. Do you think a tarp over the structure while setting the posts on top of the tarp to support the roof will make it through the winter? Any help is greatly appreciated.


In General questions | Asked By Geoffrey Cook | Dec 2 13
2 Answers

Highest R-value for under floor in attic area above ceilings

Is there a product that could be poured into holes drilled in floor with high R factor? I have looked at spray in foam, but it has to be installed in perfect temperature and is very expensive.

In Green products and materials | Asked By Raymond Pearce | Nov 28 13
12 Answers

Are there definite rules about exterior doors opening inward, or outward?

I'm putting a screen door in a woman's Condo, and her door exiting onto her back deck, opens outward. So she wants the screen on the inside! I have never seen this. Is this common?

In Building Code Questions | Asked By Adam Beckman | Aug 1 10
2 Answers

Which is more efficient: a geothermal heat pump or a Hyper Heat inverter heat pump?

A Mitsubishi Rep. had posted a load run comparing there two systems stating that Hyper Heat Inverter would cost twice the cost of geothermal systems including installation.

In Energy efficiency and durability | Asked By william warren | Nov 29 13
3 Answers

Can copper sulphate be removed from water supply?

I have copper sulfate in my water supply confirmed by the supplier which they say is coming from my copper piping. I have a filter on my kitchen faucet so I can use the water for drinking etc. I am planning on replacing all the piping that I can reach with PVC. The house is a 50 year old rancher so I can reach everything but the short vertical runs to the kitchen and baths. The water heater is 20 plus years old so I will replace that as well. Before I do all that work I was wondering if there is an easier solution?

In Mechanicals | Asked By phillip rhudy | Nov 30 13
9 Answers

Anyone have experience with payback calculations?

I had an energy audit yesterday, and they claimed I could get a 5 year payback by adding more attic insulation. I found a payback calculation online, and that came back with 30 years. I want to do the right thing, but it also needs to make financial sense. Anyone have experience with the payback calculation? I put my specifics in the "more explanation" section. Did I do it correctly? Hoping to find someone smarter than me (that part won't be hard) to help. Thanks.
Current insulation is R30 – fiberglass

In Energy efficiency and durability | Asked By Greg Bekius | Nov 26 13
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