Multiple developers are pitching office tower projects to deal with a shortage of downtown office space in Portland.

Harsch Investment Corp. and Gerding Edlen are both considering large projects, and even TMT Development is rumored to be resuscitating their Park Avenue West Office Tower that has remained a hole in the ground since spring 2009.

In an era of a historic housing crash and recession it seems strange to be talking about a real estate boom in any sector. Yet, downtown Portland has maintained a tight vacancy rate of less than 10 percent.

Even Shorenstein Properties LLC's completion in June of the 341,000-square-foot First & Main building did not appreciably bump vacancy rates. That was due largely to the arrival of several government agencies displaced by the renovation of their former home.

"Because we've been in such a difficult economic environment for a couple years, people haven't wanted to play a lot of offense," said David Squire, managing director of the Grubb & Ellis commercial real estate office in Portland. "But if you look at the numbers, it's tight out there. If you're a large user needing 50,000 square feet or more, you're out of options."

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