The architecture industry may want to hold its collective breath, lest the faintest breeze jostle loose the growth in demand for design services registered by the American Institute of Architects' (AIA) September Architectural Billings Index (ABI). After months of minor improvements, the ABI rose by more than two points in September to a score of 50.4—the first time design activity has shown real growth since January 2008.

The AIA reports that inquiries for new projects also increased dramatically in September, rising 12.3 points to its highest level since July 2007 with a score of 62.3. Most of the growth has occurred in the commercial/industrial sector, which registered a 56.3 score on the ABI, while institutional work scored 47.9, followed by multifamily residential at 47.0 and mixed practice at 44.2. The regional breakdown shows the Northeast leading with a score of 56.7, followed by the Midwest at 51.0, the South at 47.0, and the West at 44.5.

Despite such promising signs of improvement, AIA's chief economist, Kermit Baker, Hon. AIA, cautions that it's still too early to tell whether this growth will continue. "We will need to see consistent improvement over the next few months in order to feel comfortable about the state of the design and construction industry," he noted in a statement about the ABI.

Demand for architecture services has been slowly increasing, and while it's possible that the recent growth is sustainable, many other roadblocks are still preventing a faster economic recovery, Baker added.