I have a Cal Spa PS5 that has full foam insulating most of the tub however there is little foam in the area of the pump etc and the skirting around the pump/spa pak area is not insulated at all. Can I insulate this area with styrofoam or will this area get too hot for the motor? My thought is this would obviously help retain more heat in the skirting and thus keep the heat loss down.

Any Thoughts???

Arctic spas insulate the cabinet VERY well and the shell very minimal, with the idea that the heat from the motor will help keep the hot tub warm. Motors can run in the heat hot tubs produce. You should safely be able to insulate the cabinet by the motor, but keep adequate space around the motor for airflow inside the cabinet.