Due to the weight of the water placed in your hot tub it is important that your hot tub has a strong foundation to sit on.  This is why our spas have a fully framed in floor and a double reinforced 3" thick resin floor which is why our manufacturer offers a 20 year shell structure warranty

As you can see in the pictures below some manufacturers don't provide any structural support for their foundation and only use their framing to hold panels on the hot tub.

Foundation

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