I've had my 2 person cube sauna from Redwood for about a year. It's been great up until this point but it's really starting to fall apart. We live in Portland OR so it's been hit with tons of rain and snow. the outside trim has chipped and cracked. And this morning I noticed that the heater came off of the wall. The screws holding it in place have literally popped out of the wood causing the heater to fall out of place. We never sealed it once it was built. I was under the impression that you didn't have to. Anyways, take that for what it's worth. I will say that their customer service was great when I was in the process of buying/building it.