The main drag on activity is coming from the residential market. Since 2000 the value of permits filed for residential structures have grown an astonishing 81%. Both single-family and multifamily permits have benefited from low mortgage rates and a healthy economy. However, the party is almost over.

Mortgage rates are on their way back up and as a result, the value of single-family permits will fall 2% this year and an additional 6% in 2006, to $23 billion, MHC Research & Analytics predicts. Like ENR, it is a unit of the McGraw-Hill Cos.