A growing labor shortage in the commercial real-estate industry is driving up the costs of some projects and could complicate lawmakers’ plans for a $1 trillion infrastructure-spending program, contractors say.

“Ever since we came out of the great recession, many folks in our industry have been saying: it’s coming, it’s coming, it’s coming,” said George Nash Jr., director of preconstruction for Branch and Associates, a Roanoke, Va., contractor. “Today the problem is there.”

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