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9 Answers

1.5" of rigid insulation over stucco; polyiso or EPS?

I have a stucco house in high desert New Mexico (zone 5B). The stucco is in bad shape after having been terribly abused by the previous owners, so I'm taking the opportunity to have the whole house wrapped in continuous rigid insulation as part of the re-stucco project. The boards would be applied over the existing deteriorating stucco, fastened through it and the sheathing and to the studs, and then a new 1/2" two-coat cementitious stucco cladding will be attached over it.

In Energy efficiency and durability | Asked By Nathaniel G | Oct 2 14
10 Answers

Designing a passive solar / net zero house in NC Mountains

My wife and I are designing a new mountain home in Banner Elk, NC. We are in the initial design stages with our architect and are confused by the numerous options to consider. Our house will be built in the Eagles Nest community which has a pacific northwest lodge feel. Our home site is at a 5,000 foot elevation on the mountain ridge with a northern view.

In General questions | Asked By bill Moseley | Nov 23 14
5 Answers

Locating flue hole without removing wall paneling

I am trying to install a wood stove in a room that has paneling on the walls. The chimney flue has been covered by the paneling. I'd rather not remove the paneling because it was glued to the wall when installed. I have tried several ways to do this but was not successful. I dropped a measuring tape down the chimney, took a measurement but was way too low for the flue when I laid the measurement out. Check the room next to this room and found the chimney and a sealed flue on the opposite side of the chimney. Thought about knocking out the plaster or concrete seal, still an option though.

In Green building techniques | Asked By Louie Bruno | Nov 19 14
2 Answers

What U and SHGC is needed in temperate weather conditions to achieve NetZero?

In this wonderful community, Energy Efficiency is often been in reference cold climates. I live in California and am in the architectural stages of building a NetZero house.

We have two seasons: Summer and Rainy. The rainy season lasts from November to end of Feb and during those months it can actually freeze - although I doubt if we ever have more than 5-6 freeze days a year. In the summer we never have more than 5-6 days above 90 in a year. We probably have at least 330 days of sunshine.

In Energy efficiency and durability | Asked By Katherine Bretz | Nov 24 14
2 Answers

Dense pack Q: Can fiberglass batts be extracted without demo'ing a wall?

OK, a few more insulation questions more question, then I think I've hit my quota for the week (year?) :) I want to learn a bit more about dense packing a wall just so I have that as a data point to make my final decisions.

In Green building techniques | Asked By Ryan Griffin | Nov 24 14
3 Answers

Blow cellulose into air space between 4" gap from floor to slab? Other options?

Hi, love this place, it has answered so many of my questions but this one I'm stumped on.

In General questions | Asked By Luke Kelly | Nov 25 14
13 Answers

Rigid polyiso in side attics?

As a spray foam alternative, I'm considering using continuous rigid foam along the 32ft long x 7ft slope in my side attic and just spray foaming in the lower joist bays and places where taping is difficult. The attics are about as simple as can be with no dormers or other obstructions. I will need 8" of polyiso to meet my disired R-value (R-48), while keeping the 2x4 rafter bays wide open for ventilation. There are also HVAC ducts and plumbing in the attic, which is why I'd like to convert it conditioned space.

In Green building techniques | Asked By Ryan Griffin | Nov 22 14
2 Answers

Botched weatherization retrofit

My weatherization contractor is supposed to follow the BPI (building performance institute) standards for installation. At least, this is what my contract states. The standards that I found on the BPI site state "Where soffit vents are present, and access is viable, appropriate blocking or baffles are required to provide protection from wind-washing where insulation exists." The contractor installed 2 things questionably. Well, one may fall into a bit of a gray area I guess, but the other seems just plain incorrect.

In Energy efficiency and durability | Asked By Michael Lee | Nov 24 14
2 Answers

Moisture in sleeper bays over T&G roof decking?

8 years ago. The existing clerestory low slope roof had 2x sleepers over T&G decking with insulation between with sheathing and a membrane roof over. the new addition duplicated this and the entire roof was re-roofed with a new membrane. the 2X T&G decking is exposed to the living space below and is dry...no leaks. the owner is complaining of a "Soft" roof and suspects that interior moisture is trapped in the 2X sleeper bays and rotting. any thoughts? EPD

In Building Code Questions | Asked By ed spencer | Nov 24 14
2 Answers

Material to dry in upper level deck over living space for tile

Can anyone help me with this? Flooring is Advantech, want to tile. Deck is roofed. Thanks for your help.

In GBA Pro help | Asked By Sue Miller | Nov 24 14
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