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9 Answers

Grid-tied without independence … what’s the point?

Grid-tied without independence … what !?! … what’s the point …

Just read this at RMI and was shocked at the prospect that grid-tied PV systems (and probably wind, too) are not normally run by servo mechanism that locks out the network to favor independence in the event of a grid failure. That’s just dumb.

“When The Power's Out, Solar Panels May Not Keep The Lights On”

Asked By flitch plate | Sep 29 14
4 Answers

Windows for my Pretty Good House

Hi all

Another question for the experts here at GBA--this time about what windows I should install in my Pretty Good House (PGA). I've written here before about this house and you can likely find the threads of previous questions. Basically, we're building a single level, 1700 sf house in Hood River, OR and we're trying to meet PGA and passive solar "standards". Currently, we're trying to decide what windows to put in this house, and the candidates are:

Marvin Integrity
Milgard Ultra
Intus Arcarde or Eforte

Asked By Matt Mesa | Sep 29 14
10 Answers

Please tell me why I have to put so much insulation / outsulation at the roof/celing?

This may be a stupid question.......... but, I am building a pretty passiv/aggresive house in Zone 3 and my mandated (code) R-values are as follows:

Ceiling R-value 30
Wood Frame Wall R-value 13
Mass Wall R-value i 5/8
Floor R-value 19
Basement Wall R-value c 5/13f
Slab R-value d, Depth 0
Crawlspace Wall R-value c 5/13
Fenestration U-Factor b 0.50j
Skylight U-Factor b 0.65
Glazed fenestration SHGC b, e 0.30

Asked By leo kloop | Sep 30 14
8 Answers

Is continuous polyiso over plywood and concrete wall OK?

I have a 200-year-old timber-frame Cape in western Massachusetts. Last year we had Mass Save insulate the roof and three side walls with dense-packed cellulose. Unfortunately the fourth wall was an addition (70's or 80's) and already had fiberglass so the program couldn't do anything to improve it.

We are ready to tackle this final wall. Since the inside is finished we won't be removing the fiberglass but will be adding rigid foam to the outside.

From outside in our details will be:

  • 1 x 10 Ship Lap Siding (Vertical)
Asked By Jamie Malcolm-Brown | Sep 30 14
2 Answers

How to handle SE/SW orientation? And any experiences with Richlin windows?

I'm planning a not-quite almost-passive retrofit to a 1,400 sq. ft. 1-1/2 story Cape Cod in Minneapolis (shooting for R-40 walls & R-50-80 roof). I'm looking for a US window manufacturer who can come close to European quality without the high cost, lead time and shipping impact. Oh yeah, and the windows must be standard crank-out casement as I have no interest in tilt / turn (I've used them plenty in Europe).

Asked By Ryan Griffin | Sep 30 14
5 Answers

Cupping shingles on brand new roof?

Hi everyone,

Asked By Tony Johnson | Sep 27 14
2 Answers

Window & door header insulation options - Zone 5

2x6 stud walls, and the header’s have an inside and outside vertical 2x8, with the 2.5” center is empty. The outside sheathing is 1” polyiso with a foil (no OSB or plywood). I want to fill the headers before the windows are installed this week. Drying is to the inside, so no inside VB, and permeability is important. I was thinking 1.5” R6 Roxul ComfortBoard IS or 2” R8 EPS foam. I tried window/door spray foam, but the 2.5” gap was too large, and the foam just falls out to the floor. Am I overthinking this, and I can just stuff it with pink fiberglass?


Asked By Jeff Conners | Sep 29 14
7 Answers

Proper Approach to Insulation Under Add-On Porch

We are moving into a house that has an enclosed porch area off the rear of the house. We assume it was once an open area that was later enclosed. It is now used as a pantry. Above the enclosure is a porch for the second level. The main home is solid brick (built 1910) and the porch enclosure appears to be wood framing with vinyl siding. It sits about 2 feet off the ground - e.g. you could walk under and see underneath to the joists. We haven't moved in but during the inspection I looked under and realized there was no insulation between the joists.

Asked By Historical Work | Nov 24 12
4 Answers

Finishing concrete floor (slab on grade)

The finished first floor of our house will be the slab (8"+ monolithic) and we'll be doing the work ourselves. I'm pretty sure we're going to use EcoProCote products to prep/stain/seal the floor because we've seen good reviews and reports of people using it:

Has anyone had experience using the EcoProCote products? Good? Bad? Alternatives?

Asked By Brian Post | Sep 29 14
17 Answers

How do you insulate cob or earth bag walls in the Northeast?

Hello everyone, I am brand new to this forum even though I have been spending the last three months here reading and enjoying the comments and articles.

My wife and I are looking to build a cob house / cottage. We live in western NY where winters are snowy and there is substantial moisture. After some extensive research we do not feel completely comfortable with straw bale and are leaning towards building with Cob for all the obvious reasons. 1. it will be cheap. 2. We have lots of clay. 3. It will last, no termites, fire resistant and we can be more creative etc...

Asked By Aaron B | Sep 27 14
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