First thing to ask him would be did he put a preslope under the bench. If not, have him take it out and do so. I don't like framed benches in a shower...say nothing of a steam shower! Best is to build it out of concrete block and, yes it should be contained within the pan material.

I think he intends for the bench seat to be sloped, is that what you mean? Do you know if it's a big deal to remake (or extend) the copper pan to go under the bench? This seems to make the most sense for the long term. How long before it would become a problem, any idea? thanks!

phylhl-- Let me guess-- you're in Mass.? Copper pans, are, for all intents and purposes, outlawed just about every place else. The only reason they're still allowed in Mass. is because the plumbers union makes alot of racket to KEEP them legal. They've been outlawed elsewhere for three reasons. First, they're usually flat bottomed, and as TileTech alluded to, the pan membrane must be sloped so as to make sure all water that gets into the pan goes to the weep holes. Which brings me to point 2-- there are NO WEEPHOLES in copper pans. Any water that gets into the pan stays there, making for the perfect breeding ground for mold, mildew, and bacteria. Lastly, over time, the lime in the cement used to form the shower pan will corrode the copper, and I don't have to tell you the mess that'll make.

Good points, Bill. I would suggest you trash the idea of a copper pan....they were real popular about 30 years ago.

Get a good tile man in there and simply have him build a bench outta cinder blocks and bricks. He should slope it slightly to the drain. Now he forms a mud bed, tied in with a Kerdi Drain and coats the whole shebang, including the bench with Kerdi or Hydroban...as well as the walls. You can now install tiles on the floors and walls and expect it to last a lifetime. No preslope needed in this install and no mold problems either!

Well, the copper pan was spec'd by the architect. Any suggestions on how to mitigate the risks at this point?

Hi - mid-remodel and our builder put in the copper pan. it does not extend under the shower bench, but stops before the bench. The bench is made of wood. This will be a steam shower, about 5' long. Bench is opposite the wet wall but we will have a rain shower head on ceiling, so the bench will be splashed and of course when steaming, could become wet.

That sounds like a recipe for disaster, and a complete rebuild of your shower in a few years.

I agree. Tell your architect he has no idea what the hell he's doing, and you can tell him I said that. I completely missed the part about it being a steam shower! You need to have a completely watertight AND VAPOR TIGHT membrane that is completely integrated with the shower pan membrane! Between the fact that the bench is separate from the pan membrane,, and the fact that it's next to impossible to integrate the shower membrane with the pan membrane, this is a complete recipe for disaster, just as terricks said. Seriously. Tell him I said he has no idea of what he's doing. let him email me, or even post to me here in open forum. I'll back up what I'm saying with spec.

Bad enough when there are fly by nights installing these bathrooms!! But when someone SPECS OT OUT LIKE THIS?????

DAMN!!