Prefab systems are part of a complete piping system designed and manufactured to jobsite dimensions in order to minimize field welds. Prefab systems are delivered to the jobsite as part of a completely pre-engineered system. Thermacor can also offer stress analysis reports, heat loss/gain calculations or design help for this system as well as with others. This system is the highest quality option available. The contractor has only to assemble the numbered pieces as shown on our engineered site drawing, and then field insulate the joints.