We report on the effect of the extended geometry of a ring-dimple trap on the particle loss heating of a degenerate Fermi gas. If the Fermi level is slightly larger than the depth of the depression and a non-degenerate ‘halo’ is present, the overall heating rate is reduced compared to the bare ring case. We find that the experimentally measured heating rate of the overfilled dimples agrees well with a model of hole-induced heating caused by background gas impingement. This heating rate suppression is useful for experimental studies of fermionic superfluids in the weak pairing limit. In this case, achieving and maintaining low temperatures on long time scales is essential.