Full Foam Insulation. Full foam insulation consists of filling the area between the shell and subfloor completely with a thick layer of solid, rigid foam. These types of spas rely solely on the foam for their structural support. Over 70% of hot tubs manufactured today use this method of insulation because it is an effective way to insulate, as well as support, hot tubs. Unfortunately, there are some major drawbacks to full foam insulation.
Full foam insulation creates a nesting area for rodents and insects, especially in the winter. It is never recommended to move a full foam spa indoors after it has been previously installed outdoors. In addition, full foam insulation contributes to the depletion of the ozone layer, which is unhealthy for the environment.
Full foam insulation also makes it extremely difficult, and in some cases nearly impossible, to correct problems that may occur. This is because the insulation completely fills the spa's understructure and covers the plumbing and fixtures, making the process of detecting problems very difficult, time consuming, and costly.
Layered Insulation. Layered insulation is the method of installing layers of insulating material between the cabinet walls and the spa shell. In addition to being friendlier to the environment, layered insulation does not provide a nesting area for insects and rodents. Most importantly, this form of "blanket" insulation, if done properly, can eliminate all of the problems that are associated with repairing full foam spas.
Manufacturers create layered insulation in a variety of ways using a number of materials. Some manufacturers use a thin layer of foam, which does not provide an adequate insulating value, and creates the same problems for repairing spas as seen in full foam insulation. It is important when considering spas with layered insulation to look for materials with high insulating values. Ideally, look for manufacturers who use multiple layers of insulation.
If the spa is designed with removeable walls, it will allow you to easily move the layers of insulation aside when the spa requires any type of service. This makes finding the problem simple and little time is needed to correct the problem. Generally, with most service calls, one service technician can make a repair within one hour, greatly reducing repair costs. Though this may appear to be the ideal method of insulation, beware that most manufacturers try to cut corners. The use of an inexpensive, single layer of insulation and no insulation along the base can result in expensive heating bills.
