The art of foam filling hot tubs. This is the insulation which guarantees 4 important factors. 1) There is no wasted energy and the water temperature is retained until the cover is removed. 2) There is NO chance of the pipework within the hot tub leaking. All pipework, connections and joints are upgraded and then the full foam cements everything together. Therefore there is now no movement caused by inertia of pumps which would cause the pipework to leak. 3) The full foam reduces the noise of the water rushing through pipelines. There can be no complaints from neighbours while the hot tub is filtering in the dead of night. 4) The full foam cements everything together. The cabinet and shell would only be held together by a few rivets without the foam. With full foam all contact points between the shell and cabinet are locked together meaning that the shell cannot move or twist under the weight of water and people which is close to 2 tonne in weight.