August was the hottest month so far this year for new-home sales, the Building Industry Association’s Los Angeles-Ventura Chapter reported Thursday.

Throughout Los Angeles County, 281 newly built homes closed escrow in August, up 24.9 percent from July’s revised figure of 225. But August closings slipped 17.8 percent from 342 in August 2010.

Prices across the county were weaker both month-to-month and year-over-year. Median new-home sale prices fell 5.8 percent to $362,500 countywide in August from $385,000 in July and were off a significant 21.9 percent from the August 2010 median price of $464,250.

In the Santa Clarita Valley, August 2011 proved better on both the month and the year as 27 new homes closed escrow compared to only 15 in July and 23 a year earlier.

SCV new-home prices slipped 10.7 percent in August to $457,000 from July’s  $512,000 but were 8.4 percent better than last year’s median price of $421,500.

BIA chapter CEO Holly Schroeder welcomed the monthly volume increase but described overall sales as anemic.

“The ongoing weakness in new-home construction is a major reason why the regional and state economies have not shown the kind of strong growth we typically see after a recession,” she said. “We are continuing to work closely with city and county officials to demonstrate the need to reduce fees and provide incentives for builders to begin construction on more new homes, condos and apartments.”

In the home resale market for the same period, volume was up on the year but prices were down. The Southland Regional Association of Realtors reported last month that 19.4 more previously owned homes changed hands in August 2011 than in August 2010, but the median price fell 10.2 percent over the year to $372,500.