I’m currently attending GreenBuild, the U.S. Green Building Council‘s big annual convention. This is just the fifth iteration, but already it’s a behemoth. Last year it drew over 10,000 attendees, and this year it’s expected to best that record.

The vast trade show floor (over 700 exhibitors) testifies to the big business of green building. The show places leviathan bridge-builders next door to some guy selling composting toilets. An entire aisle is lined with suppliers of modular green roofs.

What I find interesting, though, is less the breadth of exhibitors than the depth.

Carpet companies rule the roost, commanding expansive multimedia pavilions right by the front door. Office furniture manufacturers have scattered $1,000, 100% recycled-content task chairs around the building. A few software companies catering to architects’ workflows speak to the lack of progress toward the paperless office. The Vinyl Institute has a stand, which amazingly has not yet been ransacked. And alone among all the world’s nations, the government of Canada has rented out good chunks of floor space to hawk Canadian wares.

These industries hardly have such outsized presence because they’re the construction industry’s biggest contributors to waste and environmental degradation. Hardly: by that measure, surely heating/cooling systems manufacturers (the biggest energy users in buildings) and cement makers (among the most carbon intensive industries in the world) should have their names on the lanyards encircling attendees’ necks.

Rather, the industries talking loudest about their sustainability are those in which certain companies (like Interface for carpeting and Herman Miller for office furniture) have staked their claim to fame on sustainability. Interface chairman Ray Anderson’s famed 1994 epiphany led to his company’s groundbreaking pledge to literally “leave no trace” — eliminate its ecological footprint. A few years later, other major carpet manufacturers were stumbling over one another at GreenBuild, in the pages of Metropolis magazine, and elsewhere, to out-do one another’s eco credentials.

Tellingly, Interface’s business is principally in “contract” work (i.e., for commercial buildings). Since home carpet manufacturers haven’t had to compete against Interface, ecological claims hardly merit a mention in their marketing. In fact, Interface’s own marketing for its recent entry into the home market (FLOR tiles) makes only passing reference to its considerable ecological merits.

Interestingly, many products and services tailored to the specific structure of USGBC’s Leadership in Energy and Environmental Design (LEED) rating system also show up on the trade floor. LEED-NC 2.2, the newest version of LEED for new buildings, gives credits for buildings that incorporate daylighting, treat their own wastewater, use certified-sustainable wood, and use recycled materials. Accordingly, vendors hawk skylights, water filtration systems, FSC-certified plywood, and recycled steel beams.

Other ways to reduce a building’s environmental impact aren’t specifically mentioned in LEED — say, composting facilities, or vegetable gardens, or habitats for endangered species on-site, or contributing to off-site transportation improvements — and therefore don’t find a ready market at GreenBuild. (To its credit, LEED allows a few “innovation credit” points, which the above examples could potentially be filed under.)