The best replacement for steam bath is sauna.

The best alternatives to steam bath are rated as following:
★★★★★  sauna
★★  hot plate
★  water bath
★  sauna bath

Your alternative for steam bath is not listed? Suggest!
Speaking about steam bath, one probably shouldn't forget about jacuzzi.

Other search terms related to steam bath and their ratings are:
★★★★★ jacuzzi
You have in mind a companion for steam bath and it is not yet here? Propose!



Google Trends

Scale is based on the average worldwide traffic of steam bath in all years. Click on graph for more.
steam bath
sauna
hot plate