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10 Answers

R-value at roof/wall intersection

I am located in the Albany, NY area zone 5A.

I purchased a dilapidated house and will be doing a deep energy retrofit. The siding will be torn off, most of it is rotten or soft, and I will install huber zip which should provide the air and vapor barrier. Larsen trusses will be installed and the cavity depth will be 12", ~R-40.

In Green building techniques | Asked By upstate ny | Mar 2 12
1 Answer

Indoor air quality and fiberglass insulation

Hi, two questions if someone can help me out:

1. Is formaldehyde an issue in all types of fiberglass insulation (ie, batts and loose-fill), or just in batts? In other words, if I am doing loose-fill insulation should I look for a formaldehyde free type or is all loose-fill free of formaldehyde? I ask because I see batts advertised as formaldehyde free but not loose fill (for example, the new Owens Corning formaldehyde free line only appears to be for batts).

In Green products and materials | Asked By Brian Jackson | Mar 2 12
11 Answers

Anyone back-vented Hardie lap siding over exterior insulation?

At this point we plan on building a 2x4 wall with dense pack cellulose (r-12), then 1/2" plywood, 2 layers of 2" fiber faced polyiso (r-26), WRB, 1x3 strapping and then siding. Can we use Hardie lap or Hardie panel siding? Likely a question for Hardie but they will likely say they want direct contact with sheathing and if foam, then no more than 1" thick. Their install instructions imply direct contact with sheathing but I don't see any restrictions against fastening to strapping....but maybe I missed that. Also, i'm guessing that strapping 1' O.C.

In Energy efficiency and durability | Asked By Robert Alf | Jan 11 12
0 Answers

Any soda blasters out there?

I have a customer with a large warehouse and roughly 9,000 sq ft of exterior painted brick. He would like to remove the paint and restore the building to its original look. I did some research and found that soda blasting appears to be extremely effective for this and environmentally friendly. So I looked around and found that I can rent the equipment but it was extremely pricey - $2500/week from Sunbelt. A few companies offer the equipment with 100lb hoppers for around $300.

In General questions | Asked By Charles Chiampou | Mar 2 12
3 Answers

Now we know how the insulating paint pushers can afford all those ads

Insulating paint costs $85 a gallon. No wonder the manufacturers and distributors can afford so many ads. They also issue press releases -- including one that tripped up the Journal of Light Construction, a magazine that should know better. The photo shows a page from their "Products" page (February 2012).
http://www.jlconline.com/cgi-local/viewnew.pdf/0/ebebe5b7f0c69fdde866650...
 

In Energy efficiency and durability | Asked By Martin Holladay | Mar 1 12
4 Answers

A question about bath fans

We have a steam shower in our master bath that we use a lot this time of year—we live in Chicago and have kids with perpetual colds—and the nearby windows end up with condensation on them more than I would like. We’ve begun to run the bathroom fans a lot in order to mitigate the moisture on the windows, but our fans are relatively inexpensive—and loud—ones from Broan (80 cfm/2.5 sones) that were installed by the guy who built our house and I’m beginning to think that it would be worthwhile upgrading to fans that are quieter and more powerful.

In Green products and materials | Asked By John Barry | Mar 1 12
7 Answers

Plastic pipes/ hot water tank - leaching chemicals....

Scientists say plastic chemicals leach into the heated water.
Some people choose not to believe it; perhaps because they sell or work with it - i dont know.
I prefer to stay on the careful side.
I have a hormone imbalance due to plastic chemicals found in my blood, causing me major health problems which started when all our pipes got changed over to plastic.
My water was tested and found to have much higher levels of "poly-chemicals" than non -plastic plumbed water.

My pipes are plastic, and my hot water tank is glass inside, but the tubes going in are plastic.

In Green products and materials | Asked By Lisa Walters | Feb 29 12
32 Answers

Insulating miners’ containers - Ulaanbaatar, Mongolia

Andy lives in Ulaanbaatar, Mongolia, the coldest capital in the world. Right now night time temperatures are hitting -40 F and C. He is an ecologist, fly fishing guide, and now learning green building / energy efficient building / sustainable design. He is doing some work with a local construction firm and is trying to figure out better building methods for his climate.

In Energy efficiency and durability | Asked By albert rooks | Feb 13 12
1 Answer

To insulate or not...

I just move to Florida from Massachusetts. The house has 3 inches of rock wool in the attic. There is no insulation over the garage space which is part of the house. Two of the garage cinder block walls are adjacent to the house making up two interior walls. One of those walls has a door to enter the house. Knowing I needed more insulation in the attic, I took advantage of Tampa Electric's energy aduit. The energy analyst agreed that the attic needed additional insulation, and they provide you with a coupon to help defray the cost.

In Energy efficiency and durability | Asked By Joe Pakus | Mar 1 12
6 Answers

How to properly insulate an unvented cathedral ceiling

In your recent "Musings of..." you refer to an unvented roof assembly as follows:

"The 2009 IRC (Section R806.4) allows unvented roof assemblies insulated with a combination of rigid foam insulation above the roof sheathing and air-permeable insulation in the rafter bays. (The 2009 IRC defines air-impermeable insulation as “an insulation having an air permeance equal to or less than 0.02 L/s-m² at 75 Pa pressure differential tested according to ASTM E 2178 or E 283.” Although spray foam insulation and rigid foam insulation can meet this standard, dense-packed cellulose cannot.)"

In Building Code Questions | Asked By Ralph Hill | Feb 29 12
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