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5 Answers

Attic HVAC and Radiant Barrier

As part of a major renovation/addition to our 1970 2 story colonial house, we're isolating the 2nd floor HVAC and adding a second zone for it, and the contractors want to place the equipment in our unconditioned attic. It get's pretty hot up there in the summer (even though I live in NJ), and I want to do what I can to maximize the efficiency of the HVAC equipment in the attic.

In Energy efficiency and durability | Asked By Eric Lavitsky | Apr 30 12
7 Answers

Is it possible to install cement siding to SIP panel with additional exterior foam?

Seems to be a lot of concerns regarding the use of exterior foam and cement lap siding attached to just the exterior skin of a SIP panel.

I was hoping to bring the exterior plane of the SIP wall in line with the 2" ICF foundation wall foam. My plan was SIP, 15# felt or housewrap, 1.5" foam board, 1/2" ripped plywood furring for drain plane, and cement lap siding.

This type of detail is readily available if you are attaching to a stud wall, can't find a similar detail for a SIP because of concerns about the ability of the OSB SIP skin to hold fasteners.

In Energy efficiency and durability | Asked By Kevin Klein | Apr 30 12
2 Answers

Will Bin (shellac-based primer) over 1.5" of 2-pound foam over 6" of polyiso in 2x10 rafter bays give me a vapor barrier?

In a Massachusetts coastal home I have 6" of polyiso in the rafter bays. If I spray 1.5" of 2 pound closed cell foam I get close to a vapor barrier. Will painting/sealing the cured foam with a shellac based primer (like Bin or Killz) give the code required warm side vapor barrier?

In Energy efficiency and durability | Asked By John Gorman | Apr 30 12
3 Answers

What window assembly has the highest U-factor?

I'm trying to buy windows and would like to know which assembly has the highest U-factor.

In Energy efficiency and durability | Asked By eric lechuga | Apr 29 12
18 Answers

Metal roofing

I am thinking of replacing my roof so I'm wondering about the benefits of a standing seam metal roof. I'm aware of its greater durability, but I'm wondering about the energy efficiency component. Does the energy benefit come mainly from choosing a light color? Do light colored asphalt shingles offer a comparable energy benefit?

In General questions | Asked By David Martin | Apr 19 12
8 Answers

Magic Window Innovations and Thermal Blinds

Does anyone have experience with a window manufacturer in Toronto named Magic Window Innovations? Do their claims of energy efficiency have much merit, including the use of thermal blinds, or are they guilty of green-washing as well?


In Green products and materials | Asked By Logan Lacelle | Apr 24 12
10 Answers

Creating unconditioned attic (and ducting/furnace question)

I've been reading the excellent guidance on attics here: http://www.greenbuildingadvisor.com/blogs/dept/musings/creating-conditio...

I'm in Austin TX, so that's zone 2. We almost never get snow, but we do have humid periods. The current attic is a very complex shape, with multiple gables, valleys etc.

In Green building techniques | Asked By James Howison | Apr 28 12
6 Answers

How to flash sill on a flanged window?

I installed Anderson flanged fiberglass windows using 2X2 around the opening and then 1 1/2 inch polyiso outside of that so that it is flush with the 2x2. I will use 3/4 inch furring strips to develop the rain plane and then place 3/4 inch T &G cedar siding oriented vertically. So I am pondering on how to extend the sill past the lip of the window to divert water away to the outside of the siding at the window bottom because that edge is to the inside of the outside edge of the siding. Because it is flanged, how do I extend the sill to overlap the siding below and attach it?

In General questions | Asked By Steve dorsey | Apr 27 12
3 Answers

HRV/ERV vs exhaust only issue...

I'm looking for some advice on ventilation. I live in VT in a house I built in 1997-- 1800 sqft, fairly well insulated, tight but not super-tight, main heat source is woodfired thermal mass heater. Open floor plans. Ac/H were estimated (not tested) at .5 at the time of construction.

In Mechanicals | Asked By Raphael Worrick | Apr 26 12
3 Answers

Under cabin insulation

Hi All,

I am planning my cabin build and I want to insulate the floors. The supporting beams will sit 12" off the ground, resting on Metal Techno posts, with 2x8 floor joists over the beams (16 OC). Not only do I need to insulate correctly but I most make sure that it is done in a way that insures no rodents can get in there.

In Green building techniques | Asked By cabinseeker asgood | Apr 27 12
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