The headline purchasing managers' index for the sector has slid from 60.8 to 60, while analysts had expected to see a small increase to 61.
Momentum in the sector has been tremendous, with January seeing a high of 64.6. Any number above 50 implies an expansion in the sector; one above 60 suggests that it's roaring.
Tim Moore, senior economist at Markit, says that the sector is "enjoying its strongest overall phase of expansion since the summer of 2007."
World First's Jeremy Cook cites the end of the renovation and restoration work needed following the winter floods in the South West, which has seen the growth of construction slow down.