The Swelt and Swole is a hybrid facility and Theron's personal "home" in nowhere. The facility has a multitude of functions. Primarily it is a temple to Sarenrae, however it also includes a Gym for physical training, as well as an Arena to hold friendly competitions (and also serve as a point of income broadcasting as a spectator sport).
The facility is designed to keep the internal temperature at a "comfortable" temperature, around 110° F, by means of a series of flexible lenses and and light diffusion features in the roof. Acknowledging that this might be a bit much for the races of the material plane, there are rest areas placed around the facility that are much cooler, and there are plenty of water sources around to keep people hydrated and safe.
The facility is designed to keep the internal temperature at a "comfortable" temperature, around 110° F, by means of a series of flexible lenses and and light diffusion features in the roof. Acknowledging that this might be a bit much for the races of the material plane, there are rest areas placed around the facility that are much cooler, and there are plenty of water sources around to keep people hydrated and safe.