If you're asking thickness, thinking that you can refinish it at some point in time if need be – just remember, bamboo is a woody grass, it is not wood, and therefore does not refinish the same way wood does. Also, if gluing a solid bamboo to the subfloor, make certain to use a urethane adhesive, but even then, I would still be nervous about it absorbing moisture. I would recommend plastic, plywood, felt, and nailing the floor.
References :
Flooring manager, retail store – 10 years