US Patent 9750376 Portable spa construction

Spa side panels are trapezoidally-shaped and mounted in respective grooves defined by adjacent tapered corner pieces and their mounting brackets to accommodate differences in coefficients of expansion of the respective parts and prevent structural damage. Angled force transfer members are configured to mate with swept back side surfaces of a spa base pan to achieve a pedestal appearance, and the bottom surface of the base pan is constructed to reduce heat transfer to the spa support surface.