Indoor Dog Park The evolution. Furball Fitness headquarters began as a big ol’ empty warehouse! After sweeping away the dust, I power-washed this baby top to bottom. Then, it was time to transform the place. Roll out the turf! Piece by piece, the AirDrain ventilation and drainage system was installed. And now the other side! This under-layer allows for cleanliness through proper disposal of waste. The final product: Furball Fitness’ indoor dog park!