Construction employment increased by 28,000 jobs in August, following a dip in hiring and spending in July, according to a workforce survey by the Associated General Contractors of America.

The association says construction job growth would have been even higher but a majority of respondents report a hard time finding qualified workers.

"Construction firms have stayed busy, adding employees in the past year at nearly twice the rate of employers throughout the economy, but more than two-thirds of contractors report difficulty finding craft workers as the number of unemployed, experienced construction workers hit a 17-year low in August," Ken Simonson, the association's chief economist, said in a statement.

"Although construction spending has fluctuated recently, many contractors are still looking for qualified craft workers and project managers."