As noted in NZBC Clause D1 Access Routes, accessible stairways and accessible ramps shall have handrails provided on both sides of accessible stairways and on both sides of accessible ramps where the ramp slope is steeper than 1 in 20.
Any stairway which exceeds 2.0m in width shall have handrails on both sides and, where the width exceeds 4.0m, shall also have an intermediate handrail provided at the centre of the stairway.
Under NZBC, handrails shall be designed to comply with the following:
• Handrails shall have the same slope as the pitchline, begin no further than the second riser from the lower end of the Stairway, and extend the full length of the stairway they serve.
• Where the handrail serves an accessable stairway or ramp, a 300mm (minimum) horizontal extension shall be provided at each end of the handrail.
• Handrails shall be positioned between 900mm and 1m above the pitchline.
• A clearspace between a handrail and an adjacent wall or other obstruction must be between 45 to 60mm as shown below.
• Handrails are to have no obstruction to the passage of a hand along the rail.
Please note that there are more requirements stated under the NZBC and that the above list is only a selection of them.
The comparison below shows the requirements detailed in NZBC Clause D1 versus the Moddex Assistrail AR150 System.