Editor's note: USGBC has taken your comments and opened the fifth public comment period with the new draft of LEED v4 (note the name change from LEED 2012). Please post your thoughts on our LEED v4 fifth public comment forum!

The LEED 2012 fourth public comment period will be open from May 11 to May 28 (11:59 p.m. ET).

Information on the 4th public comment draft of LEED 2012 is available on the USGBC website.

Now in its seventh year, the annual gathering of Living Building Challenge project teams and their kin—known as Living Future—has really hit its stride.

This is part of an ongoing series. Read all the Sticky Business posts here.

Eliminating our use of fossil fuels is an admirable goal; how do we do that?

Making plastic from corn, soy, or sugarcane has some advantages--but fixing the petroleum problem barely touches what's wrong with PVC.

What if all of the common plastics in use today were made from renewable materials rather than from fossil fuels? Would they start looking better in the eyes of environmentalists?

Reflections on the founding of BuildingGreen and our evolution as a company.

Last week, I reflected on Earth Day and how concern for the environment inspired me in school and then led to my focus on renewable energy starting in the mid-1970s.

Update: LEEDuser's interview with Sarah Alexander, with your questions, has been posted below.

If you had five minutes with the Director of LEED Certification for the Green Building Certification Institute (GBCI), what would you want to talk with her about? What questions would you ask or what feedback would you give?

I recently was on the phone with Sarah Alexander, who has that very title at GBCI, and mentioned that our members might have quite a few questions for her. She offered to take anything we could throw at her, with the help of her staff.

Windows are a big investment, and while they may look great on paper, how well do they hold up once installed? Do they meet your performance specifications? How responsive was the company to answering your questions and responding to complaints?

Windows are a big investment, and while they may look great on paper, how well do they hold up once installed? Do they meet your performance specifications? How responsive was the company to answering your questions and responding to complaints?

The GreenSpec team has already combed the world of windows available in the U.S. and Canada for manufacturers that can meet our tough performance specifications.

One might think that an unfinished wood floor is devoid of synthetic chemicals. It sure looks that way--but toxic preservatives may lie in plain sight.

Moist lumber is susceptible to fungal staining. This staining does not cause physical decay, but it looks bad. Commonly called "blue stain," the offending fungi may be yellow, orange, purple, gray, or red in addition to shades of blue. The stain penetrates into the sapwood and cannot be removed by resurfacing.

High-VOC content is still the norm in clear wood finishes, but depending on the application you can minimize exposure and maximize durability.

Clear finishes can help protect woodwork against aging, scratches, moisture, and the chemicals found in common cleaners.

Free LEEDuser Webcast

Thurs. April 26, 2012 | 3 p.m. EDT

As we've seen from the LEED 2012 drafts and public comment periods, major changes are underway for the LEED rating systems. So many changes resulted from the 3rd public comment period, in fact, that USGBC announced a 4th public comment period, to run May 1–15.