In researching the installing of adequate vapor barriers for steam showers, I learned that the manufactures of steam generators specifically provide no instructions or assistance. Their feeling seems to be there is too much liability in this and too much opportunity for contractors to do the right thing, but do it wrong, then blame them.
For that reason, the information I’m providing here was obtains from various contractor websites and is a mixing of various ideas I came across.
Perhaps the single most important aspect is there are at least two strong layers of moisture barrier above and beyond what is usually done for showers.
The Solera Group provides expert bathroom remodeling services in the greater San Jose metro area.
Slope the Ceiling
The steam will rise and condense on the ceiling. If the ceiling is flat, drops will randomly drop on the person taking the steam shower. By sloping they ceiling you cause those drops to flow to the wall where they come down without falling on the person.
This is a two person job. Install 6 mil plastic directly onto the studs in the walls and the joists in the ceiling. Use plastic sheets as large as you can in order to minimize the need for seams. This requires two people, one to stretch the plastic, the other to attach it.
Never forget that water flows down, and similar to how roof tiles are installed, start at the bottom and go across.
Every location where the plastic is punctured is to be caulked with pure silicon caulk.
Where you must overlap, overlap by at least 12 inches and always keep in mind that water flowing down must fall INTO the shower enclosure, never away from it.
This is as true of the ceiling as it is of the walls.
Photo credit: Website of Superior Sauna and Steam
Install standard cement board, and seal the seams with mesh tape and thinset.
Every inch of the exposed cement board is to be coated with a roll on water proof barrier product such as Hydro Ban.
Install tile and grout as for any shower. If using a porous natural stone, apply a high quality sealant to seal the stone. As this will need to be repeated every two years, I suggest steam showers NOT be finished with porous natural stone. If you forget or put this off, the damage the steam causes can be a serious problem down the road.
The various fixtures (valve, shower head, steam shower digital controls, etc) come with o rings or gaskets. Use them. If they’re broken or missing, replace them.
Need help with your bathroom remodel? Please contact us…..