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3 Answers

Open-cell spray foam warning!

We live in the Pittsburgh PA area, which I believe is in climate Zone 5. This is more of a warning to anyone considering open cell spray foam, or anyone that may currently have it. We had the foam sprayed in our attic back in 2007 to including attic walls, gables, and roof decking which gave us the "closed envelope"/ un-vented attic (approx 1800 sq ft of living space). The thickness of the foam was from 6 " to 10" depending on the area. The gable walls were sprayed to the thickness of 3 1/2 ". Our attic is a walk-in, soon to be a future living space.

In Energy efficiency and durability | Asked By J Murphy | Sep 8 12
1 Answer

Any word on why does the site seems to go "down" every day?

site seems to be down nearly all the time.............or bugged out at least. anyone else not able to access the site with "access denied" messages..........???????

In GBA Pro help | Asked By brad hardie | Sep 9 12
1 Answer

Basement foam insulation

should you spray foam basement walls

In General questions | Asked By doug sinclair | Sep 9 12
4 Answers

Architectural dormer meeting hot roof - insulate roof or floor?

You guys have been a help so far and I need to ask another question which I haven't been able to answer via web searches.

We have a 1.5 story ranch built ~1950, with masonry walls on the 1st story. The upstairs has two bedrooms, one of which we are replacing the insulation in right now. The room is almost completely gutted and I'm planning a hot roof approach with rigid foam hacked and stacked between the 2x6 rafters with 2" foil polyiso under the rafters. Right now, we're chasing down some recycled foam to go between the rafters to lessen the overall cost.

In General questions | Asked By Nick Horz | Sep 8 12
1 Answer

Chimney and ceiling insulation

I've been struggling with how to "legally" and safely get a class a chimney through r80 insulation in a ceiling The listed hardware only accommodates 10" of insulation above framing. Is the only alternative build a plywood box (chase) that provides 2" clearance around the chimney from ceiling to roof? Would an 8 sided duct made of duct board be a safe and legal "chase"? Can the "chase" end short of the roof?

In General questions | Asked By Jerry Liebler | Sep 8 12
2 Answers

How do I insulate a room with a concrete floor and concrete roof?

This room is used year round. The room has a garage underneath the floor. The ceiling is also the roof which only has a rubber sheeted on the outside. We live in Pittsburgh which is very cold for a good 4-6 months of the year with snow, and reasonable amount of rain in the season.

The height of the room is only 7.5 ft. So interior clearance for insulation is at a premium. Can we insulate from the outside on the roof and subfloor?

The walls are made of concrete block with firring strip, rigid foam, and drywall. I suspect it was a garage once.

Thanks for your help.

In Energy efficiency and durability | Asked By Matthai Markose | Sep 5 12
4 Answers

Framing splayed window openings with double frame walls

I'm building a double frame house with 2x4 ext, 2x3 int offset. I know that usually people line up the interior and exterior framing at doors and windows to make the boxes. Are there any words of wisdom or ideas about details for building boxes for "outie-style" windows with sides that are splayed out at 45 degrees?


In Green building techniques | Asked By tim desmond | Sep 5 12
3 Answers

Problems with mini-splits?

I'm looking into mini-splits for my new house (2700 sqft SIP construction zone 3) but my HVAC contractor mentioned that they have had a terrible time with sensors failing on both the indoor and outdoor units. His feeling is that their complexity and maintenance costs outweigh any efficiencies. Does anyone have any experience with mini-split maintenance?

In Mechanicals | Asked By Chris Baddorf | Sep 7 12
3 Answers

In western NC I am considering using 7" of closed cell foam in a retrofit project and wonder what costs are/ sq. ft.?

in a retrofit cathedral ceiling. Any idea of cost per sq.ft.?

In Green products and materials | Asked By John Duncan | Sep 6 12
2 Answers

Is painting brick fascia good, bad?

My wife wants me to paint the brick fascia on our circa 1965 house located near Baltimore, Maryland, zone 4A. What are the pros and cons of doing this with respect to reservoir effects. If it is ok is any special prep work required and what kind of paint should I use? Also, I notice there are no weep holes; was this common in the mid 1960s; is it something I should do something about? Thanks for any help.

In General questions | Asked By Windsor Furr | Sep 6 12
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