A flat walkway with a slip on it is embarrassing. A step with a slip on it is an ambulance. That is not a dramatic way of putting it, it is just where the consequences differ, and it is why exterior steps get more texture than the path they belong to.
Why steps are different
Three reasons, all mechanical.
Weight transfer. On flat ground your weight lands roughly over your foot. On a step it lands on the front of the foot at the nosing, which is the smallest contact patch and the one furthest from the centre of the tread.
The nosing collects water. It is the exposed edge, it dries last, and in February it holds a film of ice long after the tread has cleared.
Recovery is not available. Slip on a path and you usually catch yourself. Slip on a step and there is nowhere to put the other foot.
So the specification changes. Same system, more aggressive texture on treads and nosings than on the run of the walkway.
How anti slip texture actually works
An additive is broadcast into or mixed with the final topcoat. As the coat cures, the particles sit slightly proud and give the surface a controlled roughness.
The two things that get chosen are what the additive is and how much of it goes in.
Aluminium oxide is hard and aggressive. Excellent grip, and it is unkind to bare skin and to mops.
Polymer grit is softer and rounder. Less aggressive, much more comfortable underfoot, easier to clean.
Silica sand is the traditional option and sits between them.
For an exterior walkway with shoes on it, an aggressive additive is fine and correct. For a pool deck where people are barefoot, it is not, and the choice flips.
The trade against cleanability
More texture is more grip and more places for dirt to sit. A very aggressive surface outdoors collects grit, needs a stiff brush rather than a broom, and holds moss in shade.
That is a real trade, and it is a conversation to have per area rather than a single decision for the whole property. Steps aggressive, main walkway moderate, a covered porch lighter still.
The parts people forget
The landing at the top. Coming out of a door onto a slick landing is the same problem as the steps and it gets missed constantly.
Where the walkway meets the driveway. A transition between two surfaces with different grip is its own hazard, especially at night.
Under a downspout. That patch is wet more than anything else on the property, stays green, and is exactly where people walk.
Handrail bases. Not a coating question, but if we are working on your steps and the rail is loose, we will mention it.
Winter
A textured coated step is better than bare concrete in ice, and it is not a substitute for clearing and treating it. Nothing is. What the coating does is stop water getting into the concrete, so the step is not spalling and crumbling at the nosing, which is its own hazard by year ten.
Related
- Patios and walkways
- Pool deck slip resistance, where the trade off flips
- When exterior work can be done
Reference
Exterior concrete deteriorates fastest at exposed edges through freeze thaw, which is why step nosings fail first. See the Pennsylvania Aggregates and Concrete Association on scaling.