Treads are the most important element of every staircase, considering that it is the tread surface that is most exposed to wear and tear, and is also most exposed to bending depending on the bending of the substructure. The most common tread thickness is 3 cm, but depending on various conditions, they can be made from 2 cm (in the case of narrow stairs with a rigid base where there is no bending). When treads are laid on metal substructures where bending of the base is significantly more pronounced, it is necessary to choose a stone with high bending strength for the treads, it is necessary to choose a thicker stone, and often it is necessary to strengthen the treads by installing reinforcing strips.
Depending on the floor plan projection of the stairs, treads can be regular or irregular. Correct treads are easily defined geometrically, and a list of measurements or a simple sketch is sufficient for ordering. Irregular treads are impossible or too complex to describe geometrically, so in that case, in order to create a tread, it is necessary to create a template.