Ask the Experts Q&As are culled from member inquiries to NTCA’s Technical Team. To become a member and make use of personal, targeted answers from NTCA’s Technical Team to your installation questions, contact Jim Olson at [email protected].
QUESTION
I am a member of your organization and a tile contractor. I am building a residential steam shower and I had a question regarding the slope of the ceiling.
I know it is supposed to be sloped 2″ per foot, but the customer does not want that. The GC is only having it sloped down about 4″ over 5 feet. When they sloped the shower they left about a 6″ flat spot before the slope starts.
Is this typical to see in a steam shower? The flat spot would correspond to the stone curb and pony wall where the glass will get mounted.
The only steam shower I’ve ever seen was sloped the whole distance of the ceiling until the tile ended.
I just want to make sure I address this now before it’s too late.
ANSWER
Thank you for being an NTCA member. Tile contractors like you are the backbone of our association. I am glad you contacted us with your question. The right time to raise the question is during the design phase and at last resort before the tile installation begins.
When it comes to steam showers, ceiling slope is among the most common questions we are asked.
Take a look at your 2024 edition of the TCNA Handbook and find methods SR613-24 and SR614-24 on pages 282 – 285.
Under the Requirements section in both methods you will find a bullet that reads: “Slope ceiling minimum 2″ per foot to avoid condensate dripping onto occupants; sloping ceiling from center can minimize rundown on walls.” This statement is clear on its face. The ceiling must be sloped a “….MINIMUM OF 2″ PER FOOT TO AVOID CONDENSATE DRIPPING ONTO OCCUPANTS…”.
This isn’t about aesthetics. The method recognizes that some steam showers are large, and a properly-pitched ceiling with a long run of 2″ / 12″ slope can shed quite a bit of condensation down the walls. The bullet statement helps mitigate this by noting “…sloping the ceiling from center can minimize rundown on walls.” Sloping from a center point can also provide a means to alter the design aesthetics while maintaining proper minimum slope of 2″ per foot to shed condensation to the walls.
Our tile industry standards and methods are written, vetted, balloted, published and followed by well-informed industry professionals to create beautiful installations that will function properly and stand the test of time. Any deviation from the standards and methods can add potential risk to performance or function or durability of the installation and to the installation contractor and their business.
The NTCA Reference Manual supports the TCNA Handbook and tile industry standards. Take a look at the Steam Rooms section on pages 270 – 271 of your copy of the 2024/2025 NTCA Reference Manual. In this Problem/Prevention/Cure section, find the Problem of “Water dripping off ceiling of steam room”. It states the Prevention for this Problem is: “Allow for minimum 2 in. per ft. slope on ceiling.” The Cure if this wasn’t adhered to during the design and installation phase is “Re-design steam room.”
Let me state this a slightly different way:
• Water dripping from the ceiling of a steam shower is a PROBLEM
• The way to PREVENT the PROBLEM is to follow the TCNA Handbook Methods SR613 or SR614 and allow for minimum 2″ per foot ceiling slope to the wall(s).
• If dripping condensation exists in a steam shower with an improperly sloped ceiling the CURE is to re-design the steam room.
Again, the tile industry published and recognized methods and references for steam showers are very clearly written for good reason. Ceiling slope in a steam shower must be a MINIMUM of 2″ per foot slope to the wall to prevent condensation from dripping on the occupants. No “un-sloped” level areas of the ceiling are described or allowed. If they were allowed, they would have been written into the method.
