31 December 2007

Is the Conference Center Green?

The LDS Conference Center may be, in a show-me-not-tell-me kind of way, the best statement received to date on the current Church position towards sustainability. When it comes down to the most sacred of Mormon spaces, Temple Square in Salt Lake City, the LDS Church is willing to send a significant statement to the world. The article, Nature Hits the Roof by Trey Popp, states, "The LDS leadership’s decision to install a green roof is beginning to look like the leading edge of a deeper religious trend." In the same article, LDS ground service manager Eldon Cannon said, "It was a desire for us to see what we could do to be conscious of the heat sink we have here in Salt Lake City … where the roof is just generating an awful lot of heat." He continues, "Temple Square is also an area people visit...We have a message we want to share with them..."

The city block, which used to be surface parking and a large gym, is now a six-acre park and has terraces of natural vegetation and wildflowers. The building is designed as an extension of the natural mountain landscape - to blend in rather than stand out. The most impressive landscaped terraces are on the back side away from Temple Square. In the middle of a downtown urban setting, you can stand in a wildgrass prairie to view the Temple. It opens up downtown and provides opportunity to view and appreciate the arguably most sacred of Mormon sites, if not the most visited.

With such a magnificent green roof, I decided to search for other green features of the building. But I was unable to find any. Apparently the project was not intended to be a green building at all. As it turns out, even calling the roof gardens a "green roof" may be a stretch. The excellent article Shades of Green by Jan Striefel states, "While a lot of green roof construction is driven by ecological considerations, this design had nothing to do with sustainability and everything to do with aesthetics and image...Traditional 'green roofs' built to meet ecological objectives usually require minimal maintenance once established. So-called intensive green roofs, with deeper soil and a wider range of plants, often need more...This roof garden requires a lot of hands-on maintenance."

According to the article, soil for a typical green roof is only about 2-3 inches thick, with no maintenance, while the Conference Center has shallow soils averaging 18 inches thick and deep soils averaging 4 feet thick. "Does the increased maintenance required of a rooftop garden cancel out any energy and resource savings? Probably," Striefel concludes.

This leads to another big feature of green roofs that appears to be missing here; water and energy savings. This is especially critical in the high-desert climate of Utah. Clean, potable water for irrigation comes at a premium. "The LDS Conference Center block, all of which is over structure, requires regular maintenance, supplemental water, and a long-term commitment to resources. It will probably never save enough energy or water to offset its high initial cost or the costs of day-to-day maintenance," Striefel continues.

While the classification of what this roof garden actually is may be in question, there are still several benefits to be found. The heat island effect and storm runoff are both reduced by the vegetation and the cavernous auditorium below is insulated by the soil above. Unfortunately we don't know how much these features help since no effort was made to monitor any water or energy savings, meaning that it was not a priority for the design team.

Finally, regarding the choice to go with native plants rather than the formal, manicured flowers covering the rest of Temple Square, the Church made the right move, which leads me to believe that aesthetics wasn't the only motivator for the roof gardens. Compared to the rest of Temple Square, this meadow changes with the seasons and presents a more realistic and natural beauty in keeping with the environment of the Salt Lake Valley.

As the Conference Center illustrates, the Church appears willing to incorporate green features, but is not yet sold on sustainability as a way of building to conserve the earths natural resources. I believe that an important milestone will be reached when the Church recognizes the value of green building features on a global scale for all LDS building projects. Temples and meetinghouses are an enormous untapped resource where the church could be a global leader in sustainability and conservation efforts and provide a valuable example to communities where these buildings take a prominent role. Read more on "Is the Conference Center Green?"