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18 Answers

Air barrier in middle of double wall in mixed climate?

I'm in central Arizona, at the cold end of the Climate Zone 2B range, where I have around four months of moderate heating and five of moderate to heavy cooling.

In Green building techniques | Asked By Jeff Cooper | Sep 20 15
5 Answers

Does surface wiring on exterior walls make sense with batt insulation?

I've read a lot about the difficulties of properly installing batt insulation. If I kept my plumbing out of exterior walls, and used surface wiring on exterior walls, would that greatly simplify installing rock wool batt insulation? Or, would there still be other obstacles?

If surface wiring would improve the performance of batt insulation, other than the purported aesthetic issues with surface wiring, is there any other reason to oppose its use?

In General questions | Asked By James Timmerberg | Sep 25 15
2 Answers

What are good thermal break details on things like hose bibs, gas meters, and exterior lighting penetrations?

In PERSIST/REMOTE wall construction with 4 to 6 inches of rigid foam outside the sheathing, furring strips over the foam, and siding attached to the furring strips, what are good ways to handle things like water pipe for faucets, natural gas supply lines, and metal electrical conduit penetrations? I don't know how to provide a good thermal break consistent with mechanically strong (metal) piping, solidly attached to the structure, exposed to the elements on the exterior that punches right through to conditioned space on the other.

In Energy efficiency and durability | Asked By Stuart Friedberg | Sep 25 15
54 Answers

Dare to DIY a mini split install?

Hi all,
Can editors step out from behind the curtain to ask opinions, too? I'm planning to redo my garage shop this Fall and although my primary heat for the space is a woodstove, I'd love to have some supplemental heating, and cooling in the summer would be great, too. I'm no schlep when it comes to remodeling work, but have never installed or seen a mini split install. Would I be a fool to try the install myself or have the kits gotten streamlined to the point that its basically plug and play, complete with factory-charged units and quick connect line sets, etc?

In Mechanicals | Asked By Justin Fink | Aug 22 13
6 Answers

Retrofitting double wall house - best approach?

Hi folks - long time reader – first time poster:

We’re currently retrofitting a duplex in Wisconsin (zone 6B, near 7A). The ultimate goal is reduce air infiltration, improve insulation, and establish proper water barriers. The original builders used almost no flashing and air sealing wasn’t done, so I intend to remove the siding and exterior OSB to find and fix any water damage that exists. The fiberglass batting will be removed, and the original windows and doors will be replaced as well.

In General questions | Asked By E Bennet | Sep 21 15
8 Answers

High humidity and smell in spray-foamed attic

Hi - I am really hoping someone can help me out. I have seen similar topics posted, but no solution.

We had the roof deck of our attic (which is also our second floor - a cape cod style house) sprayed with Covestro (formerly Bayer) Bayseal Open Cell foam. The foam seemed fine for a few months until the summer hit. With the return of hot humid weather, we started to see very high humidity in the attic spaces behind the knee walls. On hot sunny days, there is also a distinct unpleasant smell on the second floor.

In General questions | Asked By Kay Smith | Sep 24 15
10 Answers

Can ccSPF be applied to the top side of a beadboard ceiling with a hip porch roof overhead?

I am currently replacing a small roof over an enclosed porch. The porch was once just a three season room that stayed cold during the winters and had no issues. Years ago (10 or more) baseboard heat was added to allow the room to be heated minimally. Ice dams have been pretty bad the past several years and have finally waranted repair. The roof has never been vented - it didn't need to be. Of course I found that the roof boards needed to be replaced and, while removing them, discovered that the rafter tails were in bad shape too.

In Energy efficiency and durability | Asked By Jodi Gunderson | Sep 25 15
4 Answers

Has anyone else experienced mold problems from lining interior walls with corrugated tin?

The place I was renting last had a room where the walls and ceiling were lined with corrugated tin on the inside. There was also a combination AC/Heater window unit in that room. My landlord is in total denial that his remodel job caused a very serious mold infestation. I moved out after having many ongoing symptoms of toxic mold exposure and immediately I started regaining my health. I live in southwest New Mexico in a town that boasts of its hot springs where water is just below the surface of the ground. Just wondered if anyone has experienced what I have.

In Interior design | Asked By Betty Harper | Sep 24 15
1 Answer

PERSIST / REMOTE door installation quandry

OK, I have decided to build a PERSIST house with a frost protected insulated slab. Now there is a good manual on REMOTE ( A very similar type of housing), but I am stuck on how to install the door, with a bridge over the the exterior insulation..Because the door is an Innie, it will sit in line with the framing on the slab perimeter, but I have to bridge that exterior insulation somehow..
Do I inset a thick PT plywood bridge in a void in the slab to keep the door at the same height as the slab floor? This would result in a very difficult air/water/vapour detail.

Steve Young

In Green building techniques | Asked By Steve Young | Sep 25 15
0 Answers

More Roxul woes

I wanted to follow on to this thread about finding sources for
the more esoteric Roxul products. I would have added to the comment
chain over there, but doing that never seems to make the thread
actually become visible again in the "QA" section. It also relates

In Green products and materials | Asked By Hobbit _ | Sep 25 15
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