Construction activity in the Twin Cities metro area during the month is up slightly from the previous month, but down compared with last year. With no permits issued for large apartment buildings, single-family houses helped pick up some of the slack at a time when builders are busy putting foundations in the ground before the hard-winter freeze. The Builders Association of the Twin Cities said that there were 289 permits issued to build 378 new units during a four-week period ending on Oct. 24. That included 264 single family homes and 25 permits to build multi-family buildings with 16 units or less. The industry continues to suffer the wrath of a struggling economy and competition with falling prices on existing homes, but things could be worse. And they were. So far this year permits are down 2 percent and the number of units is off 22 percent compared with last year, but by both measures the industry is better off than it was during 2009, what will likely be in the worst of the downturn.