Oahu’s condominium market stayed hot in August, as buyer demand for condos hit its highest level in more than a decade after a price record set in July.

The Honolulu Board of Realtors said in a report released Wednesday that the number of condo sales on Oahu jumped 20 percent to 575 last month compared with 481 a year earlier.

There hadn’t been as many sales for a single month since August 2006 when 580 condos were sold in the midst of the prior housing market boom on the island. The all-time monthly record was set in August 2005 at 831 sales.

“Although this August’s condo sales did not break the record-high of 831 … it is still the highest we’ve seen in 11 years,” Sue Ann Lee, president of the Board of Realtors and a broker with Properties of the Pacific, said in a statement.

As for prices, condos sold for a median $419,000 last month, up 5 percent from $398,000 a year earlier. The record was $425,000 in July.

In Oahu’s single-family house market, the number of sales rose 5 percent to 362 in August from 344 in the same month last year, while the median price also increased by 5 percent to $786,250 from $747,500 in the same period. The record was $795,000 in June.

Local residential real estate brokerage firm Locations described Oahu’s housing market in its own report this week as exhibiting “strong and steady growth” in August driven by buyers competing for relatively limited inventory.

Condos, which include townhouses and units in high-rise buildings, are generally more affordable than single-family homes and have been in more demand than single-family houses, though both segments in the market have had more sales during the first eight months of this year compared with the same period last year.

For condos, sales this year through August are up 6.2 percent compared with a 3.8 percent gain for single-family houses.

“Condos and townhouses are becoming an attractive alternative for homebuyers due to the affordable price,” Lee said.

A higher pace of condo sale growth also has been aided by developers completing several new condo towers last year that have added inventory to the resale market. Projects completed last year include The Collection, Symphony Honolulu, Waiea and 400 Keawe, with roughly 1,100 units between them. By comparison, developers built far fewer single-family homes on Oahu last year.

Locations said in its report that the 11-year high for condo sale volume was remarkable because the number of units on the market available for sale is relatively low. In August, there were 1,918 condos on the market. That’s the highest inventory for any month in nearly two years, but it compares with 2,707 units on the market in August 2006 when there were about as many condo sales as there were last month.

Because of relatively low inventory, as well as other factors that include low unemployment, record tourism and low interest rates, Oahu home prices are expected to continue rising this year and for the next couple of years, according to projections by the University of Hawaii Economic Research Organization.

This year through August, the median condo sale price is $401,000, up 3.2 percent from $388,500 in the same period last year. The single-family home median sale price is up slightly more, 3.7 percent, and rose to $757,000 from $730,000 in the same time frame.