Is this the best for my rabbits health?

Okay, my rabbits have an outdoor hutch, and they have a wooden built in box. Wood is the worst! It absorbs everything and it smells and rots. And of course my rabbits have to use it as a litter box instead of a shelter box like its supposed to be. I'm going to put a roasting pan inside of the box and dump a whole bunch of pine shavings in it. So that they dont have to go on the wood and the wood wont absorb theyre pee... is this the best to do?