Speaking of Christmas trees, the state’s new building code commissioner knows a thing or two about them.

John P. Leyden, who most recently was building official for the Town of North Kingstown, started the $78,537-a-year state job Oct. 16. He co-owns, with his brother Brian, a Christmas tree farm in West Greenwich.

As building code commissioner, Leyden, 43, will be responsible for making sure all state building projects, such as the yet-to-be-built train station near T.F. Green Airport and the new dorms at the University of Rhode Island, comply with building codes. Leyden is helping to update the state building code, a new version of which is expected to be sent through the General Assembly next year. He also answers questions from municipal building officials and helps make sure the building code is interpreted the same way by officials in different municipalities.

It’s a busy job, but Leyden is doubly busy this time of year. He brings along a change of clothes to the office each day so he can head straight to the tree farm, which his father, Bob Leyden, started more than 60 years ago. The farm now has affiliated retail lots in East Greenwich and Cranston.

Between Thanksgiving and Christmas, Leyden’s life outside of his day job is “nothing but Christmas trees,” he says.

Leyden was hired to replace Daniel DeDentro, who retire. Before his North Kingstown job, Leyden held several municipal posts: first as a structural building inspector for the City of Providence, then as building official for the City of Cranston, then as the alternate building official back in Providence. Before his time in government, Leyden worked in the construction industry, starting in 1979 with William Bloom & Sons, where his father was a superintendent.

Leyden holds an associate’s degree in architectural technology from the New England Institute of Technology and is vice president of the Northeast Region Coalition for the International Code Council, representing building officials in the New England states and New York.

Leyden is an East Greenwich native, and lives there. His wife, Maureen, is a flight attendant for Continental Airlines. They have two daughters, Lauren, 25, and Caitlin, 16.