Construction spending grew 0.6% to a seasonally adjusted estimated annual rate of $851.6 billion in September, the Commerce Department reported Thursday.
Spending in August was a revised $846.2 billion.
Economists polled by Thomson Reuters expected a 0.7% increase.
Year-to-date construction spending is up 8.9%.
Private construction was up 1.3% in the month, while public construction fell 0.8%