[jlos]

I disagree with the other comments here about your extra work. Your time outside work is your own and there are a dozen reasons why there are days a nap will be beneficial (kids of almost any age come to mind). However, you probably have enough time to nap just not the place to do so.

Most jobs will give you close to an hour for lunch and maybe even another short break during the day. That's plenty of time to nap, so long as there is somewhere quiet, private, and somewhat dark to lean back and shut your eyes for 15 minutes.

Sleeping is kinda like going to the bathroom in that you need a few fixtures and some privacy. All that is needed is someway to recline with your feet up (typically better for naps than lying directly down anyway) with some privacy. That's probably reasonable to ask for as long as its during the time you already get for a break.