There is provided an insulation system and method for a transport vehicle. The system has first and second frame members; a first rigid foam insulation member extending between the first and second frame members; a second rigid foam insulation member, where a first sidewall of the first insulation member integrates with a second sidewall of the second insulation member; and, a third rigid foam insulation member where the second sidewall of the first insulation member integrates with a first sidewall of the third insulation member. Each of the insulation members is surrounded by a protective layer. When the insulation members are integrated, the second and third insulation members impart one or more compression forces on the first insulation member and on the first frame member in order to secure the first insulation member in place without use of any fastener device.