I am replacing the tub in my bathroom remodel, and the one i bought unknowingly was one without the overflow hole.
After reading this:
http://wiki.answers.com/Q/Are_bathtub_overflow_drains_required
It seems it is not necessary, so i bought a drain that pops up and down to close it to just bypass that trip lever. Then i took off the top half of the trip lever housing/overflow pipe and put a pvc cap over it (rational being this long pipe hits the tub where the hole should be and puts the whole assembly at a bad angle for the drain). After talking to my dad he was wondering if air needed to get through the overflow pipe to help it drain. Just confirming that there wont be an issue, i dont foresee one since the pipe will fill up to the level of the tub water anyway when you hit the drain...
After reading this:
http://wiki.answers.com/Q/Are_bathtub_overflow_drains_required
It seems it is not necessary, so i bought a drain that pops up and down to close it to just bypass that trip lever. Then i took off the top half of the trip lever housing/overflow pipe and put a pvc cap over it (rational being this long pipe hits the tub where the hole should be and puts the whole assembly at a bad angle for the drain). After talking to my dad he was wondering if air needed to get through the overflow pipe to help it drain. Just confirming that there wont be an issue, i dont foresee one since the pipe will fill up to the level of the tub water anyway when you hit the drain...