What dimensions are required for a Platform step for mobility frame and walker access?

Last Updated 21st January 2020

In Australia there are no Building Standards that provide recommended dimensions. Historically this was a supplementary recommendation in AS1428.2 –1992 which was revised when the current part one was aligned with the Building Code and the Access to Premises Standard.

Platform step specifications do not comply with riser and tread lengths within the Australian Building Code and should only be used to replace low rise stairs external to the home.

If the premises is a class 1 or 2 building under the Building Code of Australia (these types of buildings are the typical freestanding home, terrace and domestic dwelling but are not flats) you can still install a platform steps for four wheeled walker access as platform steps (approximately 1100mm square) are much cheaper than ramps and allow the client to mount one step at a time more safely.

However, because these are non-stanard solutions it is important that luminance contrast and  non-slip edging on the steps be incorporated as should a suitable railing.

Internally lift access of some variety is preferred. Within AS1428.2 –1992, Figure 9 showing the 'Preferred configuration of steps for users with walking frames' p 13.

These dimensions were as follows:

•     Riser height: 95-105 mm
•     Tread depth: 575 - 600 mm
•     Strip of colour contrast on step nosing: 50-75 mm
•     Material slip resistance rating: R10-R15*

*R ratings result from testing shoe-trafficked areas over a surface lubricant, where a person walks back and forth on a platform (in a laboratory). The higher the rating, the more a surface may be considered anti-slip. Generally, R10 is the accepted minimum for external areas.

It is also worth considering having two walkers one at the top for internal use and the other at the bottom for outdoor use. A lightweight walker if appropriate can be folded easily and is generally easier to carry up the steps.