For years we just used the basement for extra storage.
During the COVID lockdown there was a lot of free time to do household projects, so I took on the chore of clearing out the basement.
There were boxes plus bags down there from when we first moved in! Most of it went right into the trash bin. If I hadn’t needed it for almost a decade, why bother keeping it at all? When it was all said plus done there was a huge room open plus waiting to be repurposed. The only thing keeping the part from being a Rec Room or a spare family room was the water boiler. The water boiler sat in the corner, plus generated so much heat plus moisture it would be difficult for the room to remain occupied for long periods of time. This was why it was being used for storage in the first locale, because the water boiler made it too moderate down there. In a fit of inspiration, I realized I could kill 2 doves with 1 tile plus use the water boiler as the source for a home sauna. The water boiler would provide ambient heating plus high levels of humidity, so if I could amp that up a little more the whole basement would be an amazing wet sauna. I called an Heating in addition to A/C professional to get his expert opinion, plus he said the water boiler would be perfect for this idea, then he did advocate a modern humidity cut-off switch, so that if the air quality became dangerously damp the water boiler would turn off.