Full foam insulation, traditionally, has been used for many years. The hot tub industry is moving away from that technology. Not only is that material not recyclable but it makes repairs very difficult, expensive and often the siding is glued to the foam making repairs impossible without damaging the spa. Once the foam has to be compromised in a repair, there is no way to recuperate your insulation value. Base and perimeter insulation, commonly referred to as Heat Lock, are not only highly efficient and exceed the California Energy Guide standard, which all of the best hot tub manufacturers are required meet, but it makes access for repairs very easy, less expensive and the insulation value is not compromised. The insulation can be removed during the repair and then replaced after the completion, returning the hot tub to its original condition with no damage to your spa.