Domestic water repipe in foam roof

We are thinking of rerouting our domestic water supply up and over an existing foam roof to get rid of a slab leak. Has anyone in Cupertino Fairgrove done this procedure? We would like to cut into the foam and bury pipes under the refoamed repair to avoid freezing but I am told the code in Cupertino requires pipes to be elevated above the roof.
Any advice would be appreciated.