Is terrazzo slippery when wet?

A polished terrazzo floor is slippery when wet, and that is a property of the polish rather than of the stone. A honed or matt cement-bound floor is not, which is why wet areas are specified matte. The figure that matters is the wet rating, and it has to be quoted for the finish being supplied rather than for terrazzo in general.

Reference photograph of a terrazzo surface, s57. Not a photograph of our goods. — Honed and matt surfaces are where slip resistance is specified. Polish is not.

Reference photograph of a terrazzo surface, s43. Not a photograph of our goods. — A dark aggregate reads as slipperier than it is, because there is no reflection to judge it by.

Reference photographs. They show the material and the finish; they are not photographs of goods we made, and the colour on screen is not a colour-match.

The figures, and where each one comes from

Finish	Wet behaviour	What we would specify
Polished	low friction when wet	not for a wet area
Honed	moderate, sealed	acceptable with a matt sealer
Matt	highest of the three	where a wet rating is required
Ground	highest, unsealed	where the substrate will be dry
Epoxy	varies with the topcoat	request the wet rating in writing

Why the processes are not interchangeable

A sealer does not make a polished floor safe when wet; it can make it worse, because a filled and polished surface is closer to a wet plastic surface than a ground one is. This is the single most common terrazzo specification error we see, and it is invisible on a sample because a sample is dry.

What these figures are, and what they are not

⛔ WE DO NOT HOLD A WET SLIP RATING AND THIS PAGE DOES NOT GIVE YOU ONE.
Published classifications for polished surfaces on wet floors are adverse and this site is not going to quote a class for a finish it has not tested. When we hold a wet and dry rating for our own panels, measured to a named standard, it will be on /download/ with the method on it.

Measured data sheets and test reports

If you are specifying this

These are the forms we actually supply for this question, with production photographs where we have them:

Send a specification Ask for a sample