Technical Bulletin: Ground and Floor Surfaces

What other surface considerations affect wheelchair travel?

In addition to slip resistance requirements, wheelchair users are affected by the rolling resistance of the surface of the floor and--on exterior surfaces--by cross slope. If the rolling resistance of flooring is high, wheelchair users must avoid those areas or expend extra energy maneuvering across the surface. In a limited study of wheelchair rolling resistance, the force needed to traverse four different surfaces was measured: concrete, linoleum, low-pile carpet (loop, 0.1-inch pile height, 10 stitches/inch, 16-ounce face weight excluding backing and glue, on jute), and high-pile carpet (cut, 0.5-inch pile height, 10 stitches/inch, 40-ounce face weight excluding backing and glue, on ActionBac).

Although the study was not intended to be comprehensive, the results provide some guidance in selecting carpet. With the force needed to traverse bare concrete as a baseline, the increase in force needed to cross each surface was measured to be: +3% for linoleum; +20% for low-pile carpet, and +62% for high-pile carpet. From these results it appears that linoleum and concrete equally require minor effort; low-pile carpet requires a noticeable. though moderate, increase in effort; and high-pile carpeting requires a significant increase in effort. Although the slip resistance ratings of carpet fall within the recommended ranges for use on ramps, its rolling resistance makes most types an inappropriate finish for sloped surfaces.

Exterior ramps and walks will generally be constructed with a cross-slope (perpendicular to the direction-of-travel slope) in order to provide  positive drainage. Because the effects of cross-slope are particularly difficult for persons using wheelchairs--particularly along a steep running slope--ADAAG provisions limit accessible routes to a 2% cross-slope.