What is chequer plate?
Chequer plate (US: checker plate), also known as tread plate or diamond plate, is a rolled metal sheet with a pattern of small raised ribs or teardrops on one side. The relief gives extra grip for feet and wheels. In Dutch it is called traanplaat, literally “teardrop plate”, after the elongated raised shapes. It is made in steel, galvanised steel, stainless steel and aluminium. Aluminium is also common with a “five-bar” pattern of short parallel ribs.
Where it is used
- Floors of platforms, walkways, loading docks and work areas.
- Treads of steel stairs and step-ups.
- Covers over pits, gullies and cable trenches.
- Load floors of trailers, vans and loading ramps.
- Kick plates, door protection and edge strips in workshops and commercial spaces.
Steel or aluminium?
| Steel | Aluminium | |
|---|---|---|
| Weight | heavy | about a third of steel |
| Strength/stiffness | high | lower, so thicker plate is needed for the same span |
| Corrosion | rusts unless galvanised or stainless | does not rust, forms an oxide layer |
| Working | easy to weld | easier to cut and drill, welding needs skill |
Practical tips
- Thickness: base the thickness on span and load. A plate that deflects feels unsafe and can bend permanently; floors or treads in public areas should be designed by an engineer.
- Ordering: check whether the stated thickness includes or excludes the raised pattern.
- Support: support large plates on a frame of angle or flat bar, fixed with countersunk bolts or welding.
- Water and dirt: water sits in the pattern. Outdoors, lay the plate to a slight fall or choose open grating if drainage matters.
- Limited grip: with oil, ice or wet leaves chequer plate can be slippery. For external stairs, dedicated anti-slip nosings or grating are often safer.
- Corrosion protection: galvanise or coat untreated steel outdoors; touch up cut and drilled edges of galvanised steel with zinc-rich paint.
Related terms
- Landing
- Stair tread
- Reinforcement
- Overhanging stair tread
Want to learn more about construction terms? Visit our knowledge base at fredsdiyplans.com.