im guessing this is for guinea pigs? if so, it's fantastic. they really need this much space, but everyone gets them at a pet store and puts them in a tiny little cage *****Id need to make a higher version for our rabbits****
IKEA Kallax expedit DIY cage for my guinea pigs and hedgehog. It is 17.1 sqft total for three levels; which is larger than the suggested minimum size for 4 cavies. Mine can run full tilt and love to do laps up and down the levels; this dispels the idea that each level is too "small" because they can't run. It's still bigger than a 2x6 C&C cage and all the same natural behaviors are exhibited.