Caster tread and size
Wheel material
The wheel material of your casters should be an important consideration if you have floors that require protection. Floor-friendly casters will be a bit more expensive, due the materials being used, but will cost far less than the repairs on your tile, linoleum, laminate or hardwood floors.
For residential or office-use casters, use the following chart to help determine the tread material for your application.
E: Excellent; F: Fair: NR: Not Recommended
Wheel & Caster Size
Furniture and residential casters generally range from 1-1/2" to 3" in height, medical and institutional generally range from 2" to 5" and industrial/ commercial go from 2" to 16". The larger the wheel, the easier it will transverse small obstacles or debris, such as grout lines between tile. The larger wheels will swivel and roll more easily.