In the design of indoor winter sports facilities Computational Fluid Dynamics (CFD) simulations are used to calculate the velocity and temperature distribution throughout the space, in order to complement traditional mechanical design and increase confidence into the proposed design. This process is described here using the example of a competitive curling rink. In the introduction the capabilities and limitations of CFD simulations are briefly lined out. The physics of the model of the curling venue are described. Simulation results are presented for the velocity distribution and the temperature distribution for two different heat gain scenarios. The first scenario includes only heat gain from lights and represents the maximum potential to pre-cool the space before major events. The second scenario includes heat gains from lighting and people at maximum occupancy. The simulation results confirm that the design intent of uniformely low air speeds and temperatures can be expected to be achieved.