Nobody fails an inspection because of the middle of the floor. It is always the edges, the joints and the drains, and that is worth understanding before you spend money on a kitchen floor.
Why seams are the whole problem
A commercial kitchen floor gets hot water, animal fats, food acids and heavy foot traffic, then gets washed aggressively at the end of every service. Anything that can get into a joint will, and once it is in there it does not dry out and it does not wash out.
Quarry tile with grout has a joint every eight inches. Grout is porous, it degrades under repeated hot caustic washdown, and each degraded joint is a place where an inspector can put a probe.
A seamless resinous floor has no joints to lose. That is the argument in one sentence.
The coved base
Where the floor meets the wall, a right angle corner traps grease and water and cannot be properly cleaned. A coved base carries the floor up the wall in a radius, so the whole room can be hosed down as one continuous surface.
This is the single detail most worth paying for in a kitchen, and it is the one most often value engineered out of a cheap quote. If a proposal does not mention coving, ask why.
Thermal shock, which kills epoxy in kitchens
A kitchen floor takes boiling water and hot caustic wash over a slab that is at room temperature or colder. That is a hundred degree swing in seconds, repeatedly, every day.
Epoxy has a coefficient of thermal expansion quite different from concrete. Under repeated thermal shock it expands at a different rate from the slab it is bonded to, and eventually it delaminates in sheets.
Urethane cement is the standard answer because its thermal expansion is close to concrete. It moves with the slab rather than against it. It also goes down thick, takes an aggressive texture, and handles the chemical range a kitchen throws at it.
Slip resistance, specified rather than assumed
A kitchen floor is wet during service. The finish needs enough texture to be safe with wet shoes, and not so much that it cannot be cleaned properly, which is a real tension.
That balance is a specification decision made per area. A dish pit and a dry storage room should not have the same texture.
Drains and falls
Getting water off the floor is half the job. Two things go wrong regularly:
The coating stops short of the drain. There is a strip of bare or previously coated concrete around the drain body where everything then collects.
The fall is wrong. Water pools instead of running. A coating can correct a minor fall problem with a build up, but it is not a substitute for a floor that was laid to drain.
Downtime
Kitchens get coated overnight or between services, in sections. Urethane cement systems are back in service quickly, and the schedule gets planned before anyone arrives with a grinder.
Related
- Commercial kitchen floors
- Brewery floors, which share the thermal shock problem
- How we scope a commercial job
Reference
Preparation requirements for high build systems like urethane cement call for a deeper surface profile than thin residential coatings, as set out in Guideline 310.2R from the International Concrete Repair Institute.