The person spoke on condition of anonymity because no announcement has been made.
ESPN.com first reported that Dalembert had reached terms with Houston, a two-year deal worth $13.7 million that included a team option for the second year.
The 6-foot-11 Dalembert averaged 8.1 points and 8.2 rebounds for Sacramento last season. He played his first eight seasons in Philadelphia after the 76ers made him a first-round pick in 2001.
The Rockets were desperate to land a big man after NBA commissioner David Stern killed a three-team deal that would have brought Pau Gasol to town.