Apartment vacancy rates in Greater Des Moines increased by 1 percent in January 2010 from January 2009, as rental concessions offered to new tenants rose.

CB Richard Ellis/Hubbell Commercial’s 2010 Apartment Survey said the East Des Moines submarket showed the greatest improvement, with its vacancy rate reduced to 6.1 percent from 8.1 percent.

The submarkets with the highest vacancy rates were Ankeny and Indianola, both of which posted a January 2009 vacancy rate of 9 percent.

The survey, conducted by Carlson, Gunderson & Associates Inc., reported the overall apartment vacancy rate in January at 8 percent.

In 2009, 531 new rental apartment units were added to the Greater Des Moines market, including 185 conventional apartments and 274 condominiums, which are being offered exclusively as market rentals. The remaining 72 units are low-income housing tax credit units located in West Des Moines.

According to the Carlson Gunderson survey, about 40 percent of the market-rate projects surveyed offered some type of rental concession to new tenants, an increase from 25 percent in January 2009.

The study, which covered a sample of about 20,769 conventional apartments in 276 projects, excludes senior housing, government or subsidized units, or projects with amenities such as meals.

From January 2009 to January 2010, the change in average rents ranged from an increase of 0.59 percent for efficiency units to an increase of 1.59 percent for two-bedroom units.