A spa 11 comprises a spa shell having a generally rectangular outer upper rim 12, a generally rectangular base pan 39 of smaller width and length than the generally rectangular outer upper rim 12, a plurality of vertical support members configured to support the upper rim 12 of the spa shell, and a plurality of force transfer members 53 angled to transfer force from a respective vertical support member 51 to an interior bottom surface of the base pan 39. The base pan 39 is centrally positioned beneath and within the perimeter of the outer upper rim 12, and includes a plurality of swept back lower side surfaces 37, each extending from a respective lower edge of a respective side panel to a lower edge of the base pan 39.
