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Application

A stair tread is an edge test.

Every tread has an exposed nosing that takes the load of a foot and the impact of everything dropped on it. It is the one place a cut stone edge will fail first.

Tread
25–30 mm
Nosing
Cast, not cut
Riser
20 mm
Joint
Shadow line

Travertine look stair treads are specified at 25 to 30 mm with a formed bullnose or square nosing cast into the piece rather than cut, so the edge is not a weakened arris. Risers are usually 20 mm, and joints between tread and riser are set to a shadow line.

Why the nosing is cast

A cut nosing exposes the aggregate at the arris and leaves a sharp edge that chips. A cast nosing is moulded with a radius or a bullnose, so the edge has the same density as the body and no cut line to fail along.

The dimensions that matter

ElementTypicalNote
Tread thickness25–30 mm30 mm where the tread is cantilevered
GoingPer stair designUsually one panel cut per step
Nosing projection20–30 mmCast with the tread
Riser20 mmSet behind the tread nosing
JointShadow gapAvoid a flush butt at the nosing

Slip on stairs

A honed or fluted tread gives grip; a polished tread does not. On a public stair, the nosing is often the place for an insert or a groove, and that detail should be formed or machined before the panel leaves the plant rather than cut on site.

Questions buyers ask

What thickness should stair treads be?
25 mm for a supported tread, 30 mm if any part is cantilevered or the stair is in a public building with heavy traffic.
Can the nosing be cut on site?
It can, but a site-cut arris is the weakest point of the tread. Cast nosings arrive with the radius formed and the edge at full density.
Is travertine suitable for public stairs?
Yes, with a honed or fluted finish and a nosing detail for grip. Polished surfaces are not appropriate on a public stair.

Send the drawing. We will return a joint layout.

Panel layout, area, substrate and required delivery date are enough to start. Quotation within 24 hours.