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7 Answers

Evaluating feasibility of solar panels in site rated at 895 (or 65% TSRF)

Just got a quote from solar panel install company and thinking I may skip solar and redirect funds to doing more insulation work on the house. But before I do that, I wanted to run some thoughts by here.

1. I am calculating that per kW I will be at $4.25 installed (I am in Boston area). Considering article I just saw today on GBA pegging average installed price $0.80 less per kW I am discouraged.

Asked By Apollo S | Mar 25 15
0 Answers

Old house, Wet Brick

The picture pretty much says it all. We had terrible ice damming this year, as did just about everyone in my area; houses both old and new saw wet walls and rainy windows for the first time ever. My house was built in 1850, and I have to imagine this has been a problem before. But this was our first full winter here. I'll try to explain the situation as best I can:

Asked By Chris Ermides | Mar 26 15
2 Answers

Manual J - Calcs - Mini Splits

Zone 4B - 3,300 sqft - 2 story - R10/R25/R60 with R8 windows - open floor plan design

The calcs came in at 3.25 tons heating/cooling. Two ductless minis per floor:
3 - 9,000 Btu Mitsubishi Hyper Heat Pumps - 26 SEER - 10.5 HSPF
1 - 12,000 Btu Mitsubishi Hyper Heat Pump - 26 SEER 10.5 HSPF

$12,000 installed (P&L) for all units - 10 year warranty

Asked By Peter L | Mar 26 15
2 Answers

Attic insulation reality check

It's time to get my attic air sealed and re-insulated and I've committed to hiring it out since the 6/12 pitch truss attic is a horrible place that I hate to work in. I'm having trouble finding people willing to blow cellulose. Everyone around here seems to want to blow fiberglass. Is this a major issue?

The first bid I've gotten is $3.20/sf for attic floor air sealing and R-30 worth of blown fiberglass. Sane/insane?

Asked By Nathaniel G | Mar 26 15
6 Answers

Strapping material for rainscreen...plywood fir or spruce?

I'm ready to put the strapping on-top of my WRB, only I'm not sure what the best choice is.

I want a 3/8" gap, so cutting plywood strips is my only option (there is NO composite furring strips available in town...I called everywhere!)

I've got the option of 3/8 spruce with exterior glue, or 3/8 fur with exterior glue.

Does either have a lower tannin content that may deteriorate the WRB? Do I even have to worry about that? Should I back prime the strapping to avoid this?

I'm going to put cement board over the strapping then stone.

Thanks!

Asked By Mark Helmrich | Mar 16 15
26 Answers

Structural Insulated Panel (SIP) roof decay

I have a BensonWood timber frame in Vt that is only 8 years old with significant panel roof decay. So much so that my standing-seam metal roof has begun to rust from the inside out. There is evidence of SIP seam failure in several places below the standing-seam metal roof. Is it likely this was the cause? It is a hot roof.

Asked By gregory raith | Oct 3 11
8 Answers

Alpen vs Inline

Hello,

I am comparing Alpen and Inline products. I have recieved quotations from both companies and I would like to pose a few questions to those that have a little more experience in this relam.

Both companies use fiberglass frames and Cardinal Low E Glass. Inline makes their frame and Alpen purchases the frame material through Inline.

Alpen makes a double pane window, their 525-s Series, that have a whole window U-factor of .19 for casements and .15 for pictures. Inline offers a triple pane window with a whole window u-factor of .17 for a casement and .14 for a picture.

Asked By David Mosijchuk | Mar 25 15
4 Answers

Insulating truss joists 16" on center — Best way?

Batt insulation for 24" o.c. The 2x lumber is 23" wide. The truss joists I'm looking at are 2x4 lumber 24" o.c. The space between the trusses is 21.5". Does anyone know if R-19 batts are available in 21.5 or 22"? Seems like squeezing a 23" wide batt will not work well.

Also the tiger wires used on 2x lumber will not work well on a truss. Is there another method of holding the batts up to the floor?

Asked By Walter Gayeski | Mar 25 15
6 Answers

Insulating scissor truss

Hi, I am building my first house, what a project that has turned out to be but that's for another day. Anyways, our great room has scissor trusses for a nice pitched ceiling. I would like to have at least 24" of insulation to keep things nice and toasty in the winter. There is a 4' overhang outside on either end. I nailed a 24" high plywood leaving a vent space above where the red is on the layout. My question is what material and how to go about it. To use the high density cellulose is has to be contained by some mesh? Any input appreciated.

Asked By Tom Smith | Jul 19 14
6 Answers

Suggestions/advice on vapor barrier product to use?

In the basement of my house (built in 1900) in NE Ohio...Half of the basement floor is finished, the other half is dirt floor covered by a few inches of crushed stone gravel. I had a mold issue, so looking to put a vapor barrier over the gravel floor. Also am getting slightly elevated radon level about about 4.9 to 5.1. I'm hoping maybe to solve both issue with one fix. Here's my dilema...I'm looking for a vapor barrier material that would withstand occassionally walking across it.

Asked By Justin Stine | Mar 25 15
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