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0 Answers

Two reports from the recent NESEA conference

Two bloggers have posted reports from the recent NESEA conference in Boston:

David Guenette's report

Kevin Ireton's report

In Energy efficiency and durability | Asked By Martin Holladay | Mar 20 13
3 Answers

Window verification - glazing specs

We are building a small home in W Virginia . we have designed some passive solar elements for it .
The windows for the southern side came in and are nailed up but not sided in yet.
I checked the sticker on these windows and it doesn't match the specs.for the order , the sticker has .15 u and .27

solar heat gain. The order called for .21 u and .46 solar heat gain. The company is Fibertec and I called and they said they are just wrong lables and that the windows are as per the specs. Is there a way to verify
the they are correct ? these windows are a key part of our pass solar design.

In General questions | Asked By john sereday | Mar 19 13
5 Answers

Minisplit in California

I'm planning a 640 ft2 granny unit in coastal california. I searched through the blogs and didn't find the answers I need. The building will be freestanding and highly insulated. I want to use a mini split since I need some cooling capacity even though it is only 1 mile from the ocean(Zone 3). The occupant has MS and people with MS overheat very easily. Can anyone recommend a mini-split that is APPROVED by the CEC for use in California. I have spent some time looking through their database but I find it impossible to find anything there.


In Mechanicals | Asked By Stephen Houlihan | Mar 14 13
1 Answer

Roofing Underlayment as WRB on Side Wall

What are the problems, if any, with using Roofing Underlayment on the side wall as a weather-resistant barrier, provided that the product has the desired physical characteristics (perm rating, etc...)?

In General questions | Asked By Jonathan Lindstrom | Mar 19 13
3 Answers

Corrugated metal systems?

I'm planning a small structure in hot, humid Florida (climate zone 2). In contemplating materials for the roofing and siding, corrugated metal appeals to me because it's affordable, green, and provides two specific advantages that Florida needs: strength against hurricane debris impacts, and the potential for a reflective surface coat to mitigate heat gain.

In Green building techniques | Asked By Andrew Wright | Mar 19 13
8 Answers

Double stud wall assembly

I am building my dream house outside of Seattle in climate zone 4C with 4,615 heating degree days. It will be a net zero energy home built to Passive House standards. A 10 kW solar array will generate all of the energy the house uses with enough left over to power an electric car for 3,000 mile/yr. With solar panels now selling for $1/watt I can buy the panels, inverter, wire and mounts for under $20,000. Even in Seattle's rainy climate, this system will pay for itself in six years if I install it myself and in 11 years if I hire professionals. But I digress....

In PassivHaus | Asked By Gerald Blycker | Mar 15 13
10 Answers

SCIPs Please?

I’ve been reading about SCIPs (Structural Concrete Insulated Panels) as another approach to my hopeful project for a single story ranch in Zone 3. I’m not finding objective (i.e., third party) information on SCIP performance and, even more, on detailing them as walls or other panels in a building enclosure.

I could go to the individual mfgrs, but would love to find I’d missed something here, or at BSC …

In Green products and materials | Asked By Joe Wilson | Oct 26 10
4 Answers

Siding update with insulation install - but no sheathing

Hello Everyone.

New here, but have been trying to suck up the knowledge as best as possible. Im sure this is the first of several questions, so forgive me if Im not providing enough/the right info to get things started.

I own an old farmhouse, right on the 5A/6A climate border. Its a foursquare type, with a few additions tacked on the back of it. My questions focus on the main part of the house, since its mostly original everywhere. Build date is circa 1880, built with a mix of new/reclaimed timbers (based on beams in the basement).

In GBA Pro help | Asked By Scott Clark | Mar 18 13
0 Answers

Selecting an HVAC and hot water systems

We are building a new house. I need to select the guts for the heating/cooling. Solar and geothermal are not feasible. How does one whittle down the options/brands/models for a high efficiency (.95+) gas furnace? My builder is recommending a Trane furnace and cooling units. For hot water, he is suggesting tankless Navien units (NR-240A). I'm just not sure how to consider other brands and/or options. Any suggestions are greatly appreciated.

In Mechanicals | Asked By scott sch | Mar 19 13
11 Answers

Load sharing in double stud walls

The advice given here repeatedly is that only one of the walls in a double stud assembly should be load bearing. OK so I'll put all the necessary structural " stuff" in one and the other will be built as light as possible. Must anything be done to PREVENT load sharing?

In Energy efficiency and durability | Asked By Jerry Liebler | Mar 18 13
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