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1 Answer

Rigid foam over WRB

I am finishing up a full kitchen remodel that pretty much required me to rebuild 25' of exterior wall in my 1600 s.f. 1950s ranch located in Portland, Oregon (zone 4 marine). It is a 2x4 wall with R-15 fiberglass, existing 1x8 shiplap board sheathing (less some areas with wood damage, yes we do have termites in the NW), window and door rough openings flashed to a Tyvek primary WRB and air barrier. I would like to add 1-1/2" of rigid foam with taped seams and a 1/2" rainscreen before replacing my cladding.

In Energy efficiency and durability | Asked By David Fraser | Nov 19 14
3 Answers

Retrofit an existing exterior wall to 1-hour rating

I have a small garage conversion project that is within the side and rear yard setbacks and requires one-hour rated walls, eaves for approval. Any thoughts and solutions that balance compliance and a small budget (i.e. demo and rebuild, exterior versus interior modification). USG wall assemblies suggest 1/2" Ply and then exterior wall board (but the garage is now sided with lap siding).

Thank you

In Building Code Questions | Asked By Robert Saladoff | Nov 19 14
6 Answers

Mixed-humid insulation recommendations

I've read a great deal about building science and energy-efficient building practices. This site is a great resource. I think I understand the theory, but I have a few questions that are perhaps best answered by experience.

In Green building techniques | Asked By Jeffrey S | Nov 16 14
11 Answers

Air sealing and insulation question

I am buying a 1900 bungalow in the white mountains of NH, 10 foot ceilings 4 inch walls. The only insulation now is the attic is capped. The heating is hot air, with unsealed or insulated duct work. The house is one story. We are closing in October, so I'll have no access until then. Where should I start?

In Energy efficiency and durability | Asked By Ken Chester | Aug 12 14
11 Answers

Air sealing and insulation question

I am buying a 1900 bungalow in the white mountains of NH, 10 foot ceilings 4 inch walls. The only insulation now is the attic is capped. The heating is hot air, with unsealed or insulated duct work. The house is one story. We are closing in October, so I'll have no access until then. Where should I start?

In General questions | Asked By Ken Chester | Aug 12 14
1 Answer

Make up air for clothes dryer; exhaust only system

In new construction with an exhaust only ventilation system, is there a need for a make up air source for an electric clothes dryer. I am toying with the idea of some supplemental passive air sources...

In Mechanicals | Asked By Robert Holland | Nov 19 14
7 Answers

My wife needs convincing ...

You all have me convinced that I can change out my Mitsu AC minisplits with some all season heating and AC cold climate heat pumps and save substantially on the energy costs over my 98% efficient boiler.

But my wife is not convinced.

In General questions | Asked By flitch plate | Nov 18 14
1 Answer

Rim joist insulation

I insulated and air sealed my rim joists using 2 and 3/4 inches of polyiso along with one part foam around edges plus an inch or a bit more of mineral wool to get me to my target of R20+. I covered the insulation with 1/2 drywall for a thermal barrier and caulked the top and side edges as well as around plumbing penetrations through the drywall. I did not caulk the bottom edge (at least as of yet) as it is hard to get a caulk gun to the area. This edge is screwed tightly against the sill plate. Given this construction, do I have any condensation issues to worry about? I live in zone 5 (NH).

In Energy efficiency and durability | Asked By Michael Lee | Nov 19 14
4 Answers

What do I do about my backdrafting oil-furnace?

Last weekend after noticing my bath fan wasn’t working. I went into my attic to see what was going on. I found the vinyl flex duct that was snaking across the attic floor full of water, so I swapped the fan for a high-quality model and did a nice job running 4-in. aluminum pipe to the outside. The fan is rated at 70 cfm and now my bath doesn’t fill with steam and my windows are no longer fogged up in the morning.

In Mechanicals | Asked By Patrick McCombe | Nov 19 14
0 Answers

Masonry tie/anchor between concrete wall and stone facade

I am looking for a masonry tie that limits thermal bridging between concrete wall and natural stone or brick facade. The planned wall assembly looks like 6-8 inch structural concrete, 7 inch rockwool insulation, 3/4 inch air gap, 4-6 inch natural or engineered stone facade.
There a wall ties from German manufacturers that reduce thermal bridging. The product is accord to the German DIN Norm and has CE certification that is valid in the EU and Scandinavia.
Are there US product that I am not aware of or is there an inexpensive way to get the foreign products approved by an inspector.

In Green building techniques | Asked By Andreas Ryll | Nov 19 14
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