Steam riser flange in floor

algis

I have a steam riser that goes through the bathroom in an old 6 story NYC coop (1920s) building.

I recently retiled the bathroom, but found my tiles were cracking around the steam pipe even though I allowed 1/4" around the pipes. What I later realized was that the pipe is expanding up and down with a flange below the previously poured screed and the my newly poured screed and tiles going up and down for the ride.

My question is: How is the area around a steam pipe usually (or properly...) prepared for tiling? I'm guessing it should there be clearance right round for the pipe flange so the entire pipe can expand up and down... unless there is some sort of thermal expansion slip joint directly below and a flange is secured to each floor.


Photo shows flange under screed that has been cleared around its circumference - there is an even larger diameter flange directly below that flange

Btw: thermal expansion of cast iron (thermal expansion coefficient = ~6.5e-6) over 6 stories (60') over 150 degF = 6.5e-6 * 150 degF * 60' * 12"/' = almost 3/4" --> unless the pipe is secured at the middle floor (I'm on the third floor), there must be some sort of expansion slip joint every 6 floors or so..

JohnNY

That's the pipe tapping on the bull of the tee that used to feed a radiator that is apparently no longer there. A bit of pipe insulation around the tee would allow for the necessary expansion.

Hap_Hazzard

I'd trim the tile to leave a gap around the pipe fitting, throw a split escutcheon around it and call it a day.

algis

Awesome! Thanks guys!

dopey27177

Typically a pipe sleeve should have been installed. The sleeve maintains the space needed to prevent the the upward movement of the pipe.

Jake

ethicalpaul

Thanks for this knowledge @JohnNY and @dopey27177 --

Here is some info I found on wiki for it: https://en.wikipedia.org/wiki/Sleeve_(construction)

I see the insulation is to prevent fire spread, cool.

But hey Jake, the sleeve allows the pipe to move up and down with expansion rather than to prevent it, right?

A (to me) pretty good explanation of the issues: https://www.metraflex.com/white_papers/understanding-the-dynamics-of-riser-design-in-skyscrapers/