The bellwether Markit/CIPS UK Construction Purchasing Managers’ Index eased from July’s 14 month peak of 55.8 to 52.9 in August.
Workloads are still expanding above the crucial 50 no-change mark but the rate of expansion was the weakest since May.
Commercial building was the best performing area of construction output in August, followed closely by residential work.
But the latest expansion of housing activity was the weakest since March.
Meanwhile, work on civil engineering projects decreased for the first time in five months.
Report author Tim Moore said: “The construction sector slipped back into a slower growth phase in August, with this summer’s catch-up effect starting to unwind after projects were delayed by adverse weather at the start of 2018.
“Civil engineering was the worst performing area of the construction sector, with output in this category falling for the first time since March amid reports citing a lack of new work on infrastructure projects.
“House building saw a particularly sharp slowdown since July, meaning that commercial construction was the fastest growing sub-sector in August.
“There are some encouraging takeaways from the latest survey, especially the resilient degree of new business growth in August and a strong upturn in staff recruitment.
“Survey respondents noted that they are confident about achieving organic growth at their businesses in the coming 12 months.
“The degree of optimism reported in August remained constrained by external factors, including domestic political uncertainty, stretched supply chains and shortages of suitably skilled labour.”