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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
3 Answers

Stranded Bamboo Flooring, Is it a good choice?

We are building a home in Alabama on the coast. We have a crawlspace sealed foundation that is dehumified. We are looking at purchasing 5/8 - 1/2 Stranded, Carbonized, bamboo flooring. We are getting mixed reviews on whether this is a good choice. We've heard the following:

Pro - it's solid engineered so it can be sanded and refinished. The color is the same all the way through. Compared to engeered wood which can only be sanded and refinished once.

Pro - Harder than most woods, and compares to engineered wood in that it's harder to scratch.

In Green products and materials | Asked By Mary Smart | Nov 20 14
5 Answers

Heat-pump water heater in conditioned space

I am building a net-zero energy home to Passive House standards in the Seattle area. The best scenario for a heat pump water heater is in an attached garage, unheated basement or in the conditioned space of a house in a humid heating climate (why doesn't everyone in Florida own one?). Unfortunately, my only option is within my conditioned space in a heating climate. My heating system will be a ductless minisplit air source heat pump. I would prefer to not remove the heat from my utility room only to make my heating system work harder.

In Mechanicals | Asked By Gerald Blycker | Nov 24 14
5 Answers

Could you please provide me of an example of a temporary one-floor sustainable building?

I am currently undergoing a project at college and i need to research temporary sustainable buildings

In General questions | Asked By Alfie Andrews | Nov 24 14
2 Answers

Round window flashing and water management

I have a situation with a remodel on a 1970's house with one round window that was replaced. The new window is installed, and the company had me replace siding and trim around the window. The window is an aluminum clad round (well, round with a flat section at the bottom, roughly 4" above where the siding stops).

We started out by installing sheathing on the wall- it had been built with no sheathing- it's a complicated wall with two round windows, and there are custom steel brackets holding everything in place (sort of).

In GBA Pro help | Asked By lavrans mathiesen | Nov 23 14
3 Answers

Mitsubishi M-Series New FH vs. Old FE models

We're in the market for an M-series heat pump and dealers have been quoting us the older FE models rather than the newer FH models. Is it a mistake to purchase an older model that will probably be discontinued sooner rather than later? I would think so. Thoughts? Thanks.

In General questions | Asked By David Greenberg | Nov 21 14
3 Answers

Windows yes, but what about doors?

I was wondering if doors in the US are also rated like windows (at least in europe) for air leakage, etc?

Any tips on reasonably priced (maybe to much to wish for) exterior door manufacturers that do a good job on air sealing their units?

I build in Northern Zone 3.

In Energy efficiency and durability | Asked By leo kloop | Nov 17 14
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