Lighting in a sauna… put some thought into this. I have a few bright ideas that may help you.
dimmer: every sauna i’ve ever built has a light in it. Every light is switched via a dimmer, just outside the sauna door on the changing room wall. WHY? soft light is most preferred in a sauna. the softer the better. I like to nude up in a sauna and if i’m taking a sauna with guys, I don’t want the lighting to make me feel like i’m in a doctor’s office. get it? A dimmer light allows for brighter light when reading in a sauna, and a brighter light is good when looking for a bottle opener or some product you lost under the bench.
candle: I have a good friend who has built saunas in remote areas, sans electricity. Build your sauna with a window on the wall to the changing room (instead of a window in your sauna door). The window sill in the changing room is a great spot to mount a candle holder. The soft light from the candle casts a wonderful glow in your sauna room (and doesn’t melt the candle!).
window: a lot of hard core sauna nuts don’t like any light in their sauna, just a window facing the lapping shoreline on their pristine lake. Who wouldn’t like that!!? I have that gig at my lake sauna, and it’s priceless. But indoor or an urban environment, a window to the changing room is the best gig. Just imagine you’re at the lake!