This year I visited the Greenbuild Conference, which was held here in Philadelphia. It's the annual event for all things related to "green" construction. It was held at the Philadelphia Convention Center, and it was enormous. The building takes up four city blocks, and the main exhibition hall is over 560,000 square feet. It was full of exhibitors (over 800) and had two stages as well as refreshment booths and rest areas. The stages had constant presentations going on, and there were seminars in the conference rooms in the rest of the building as well, plus tours of Philadelphia and the surrounding area.

I didn't attend the seminars (see here for part of the reason); my experience was limited to the exhibition floor. Even at a brisk pace, it still took two hours for me to get through everything. Here's the map of the exhibition:

Many of the exhibits were creative and informative. Of course, with topics ranging from Acoustics to Plumbing to Waste Management, there was something for everyone. I was most interested in the building materials and systems manufacturers, and also stopped by the Passive House booth.

The two biggest highlights for me were:

Several manufacturers of SIPs (Structural Insulated Panels). This is an approach to construction that uses prefabricated panels to speed on-site construction time. The manufacturers take your building plans and break the design down into manageable pieces, then build those pieces in a factory. Everything is delivered on a truck, and goes together according to their assembly diagram. The result is a well-built and well-insulated building that goes up faster than if you built it from scratch on site.

Diagrammatic view of a house built with SIPs; image from

There was another type of panel manufacturer there, too, who builds with steel framing. This system is interesting because it combines insulation between the studs (as is usually done) with continuous insulation outside of the stud space. This continuous insulation is more efficient than insulation between the studs. The system comes in panels just like the SIPs, and can even be used for basement walls. This is definitely something I want to find out more about.

Lots of high-performance windows. Windows are one of the weakest points in a building's envelope. While a code-compliant wall has an insulating value of R-13, a code-compliant window is only around R-3. If you have large windows, you're probably losing a lot of heat through them, even if they're good ones. These high-performance windows, though, typically have R-values starting at around 6, and go up to R-14 or higher. They do it by using three layers of glass (called triple-glazing) with special gases in between, and by carefully constructing the frames so that they don't transmit heat from inside to outside (or vice versa).

An energycore insulated window from QuanexI also picked up information on insulation, ventilation equipment, bamboo siding, and some really cool structural connectors. I'm glad I was able to attend. Next year the conference will be in New Orleans.

So, did you or anyone you know attend Greenbuild? What did you think?