Accessible Stairs and AS 1428.1: Opaque Risers, Nosing Strips and Handrails (NSW Guide)
An accessible stair under AS 1428.1 is a stairway that people who use a mobility aid, who have a vision impairment, or who need steady guidance can use safely and independently. The most common stair rejection we see is a feature stair that passes the NCC and fails AS 1428.1. Here is which stairs have to comply, what each part needs, and what your certifier will check.
The short answer
Where a stair must comply with AS 1428.1, it needs opaque risers, a compliant nosing with a 50 to 75 mm contrast strip, handrails on both sides with extensions, and tactile ground surface indicators at the top and bottom. Under NCC Part D4 this applies to stairways except those in areas exempted by D4D5. Fire-isolated stairs only need the nosing strip. NSW projects stay on NCC 2022 Amendment 2 until 1 May 2027, and the Premises Standards reference AS 1428.1:2021 from 29 July 2025.
Which stairs have to comply
D4D4 in plain words
NCC 2022 Amendment 2 Part D4, clause D4D4, requires every stairway, except in areas exempted by D4D5, to comply with clause 11 of AS 1428.1. Fire-isolated stairways only need the nosing provisions in clause 11.1(f) and (g). Confirm the exact wording in the edition that applies to your certificate. NSW adopts NCC 2025 on 1 May 2027.
Fire-isolated stairs
Fire-isolated stairs need the contrast nosing strip. They do not need the full opaque riser, handrail or TGSI package that applies to other accessible stairs.
Exempt areas under D4D5
Areas that D4D5 exempts from access do not need an accessible stair. See our page on D4D5 exemptions for warehouses and industrial buildings for the detail on what can be left inaccessible.
Houses and sole-occupancy units
Class 1a houses follow the Housing Provisions for stair construction, including the 125 mm sphere rule, not AS 1428.1. Stairs inside a Class 2 sole-occupancy unit are also treated differently. Common areas of Class 2 buildings still follow Part D4.
Risers: why open risers fail an access report
NCC D3D14 stops riser openings that would let a 125 mm sphere pass between treads. AS 1428.1 requires opaque risers where the stair must comply. An open-riser steel-and-timber feature stair in a foyer or office fit-out can pass the NCC construction rule and still fail the access report. The practical fix at design stage is a solid or genuinely opaque riser infill. Perforated metal or glass only works if it meets the opaque requirement in the Standard.
Treads and nosings
AS 1428.1 controls the nosing profile and limits overhangs and sloping risers. Slip resistance is set by NCC D3D15 and AS 4586. The nosing strip must be a single continuous colour, 50 to 75 mm deep, set back no more than 15 mm from the front edge, and provide at least 30% luminance contrast. If the strip is not set back, it cannot extend more than 10 mm down the riser. For the contrast calculation see luminance contrast and AS 1428.1.
Common defects at occupation certificate include strips that are too narrow, set too far back, use two colours, or are missing entirely on timber stairs.
Handrails on accessible stairs
An accessible stair needs a handrail on both sides. Height is 865 to 1,000 mm above the nosing line. The grip is circular or elliptical, typically 30 to 50 mm diameter under AS 1428.1-2009, with at least 50 mm clearance from the wall. The rail extends past the top and bottom of the flight and ends so it cannot catch clothing. Continuity across landings is required. NCC D3D22 sets a lower baseline of one side on narrower stairs and both sides when the stair is 2 m or wider; AS 1428.1 is stricter for accessible stairs. For ramp handrails see ramp handrails and kerb rails.
TGSIs at the top and bottom
NCC D4D9 and AS/NZS 1428.4.1 require tactile ground surface indicators at the top and bottom of stairs, except on fire-isolated stairs. See our page on TGSI compliance audits for layout and contrast detail.
Mezzanine stairs in warehouses and fit-outs
Whether a mezzanine stair must be accessible depends on whether the area is required to be accessible or is exempt under D4D5. Egress rules in Part D3 still apply. Where full AS 1428.1 compliance is not practical, a Performance Solution can be the workable path. See what is an NCC Performance Solution and disability access Performance Solutions.
What a certifier checks, and when
At Construction Certificate the stair sections and details should show riser infill, nosing detail with strip dimensions and luminance contrast values, and handrail details with extensions. At occupation certificate the built stair is checked against those details. The access report should state the status of each stair.
How Sydney Access Consultants helps
Sydney Access Consultants reviews drawings at DA, CC and CDC, prepares a stair-by-stair schedule in the access report, and can carry out a pre-occupation certificate audit. Where a stair cannot reasonably meet Deemed-to-Satisfy, we document a Performance Solution. See access reports for DA and CC, services and what certifiers want in an access report. Ask about a drawings review on (02) 9586 3111.
Frequently asked questions
Do accessible stairs need closed risers in Australia?
Yes. Where a stair has to comply with AS 1428.1, which under NCC Part D4 covers most stairways in buildings other than houses, the risers must be opaque. The NCC's general stair rule only stops openings that would let a 125 mm sphere pass between treads, so an open-riser feature stair can meet the NCC's construction rules and still fail an access report. Fire-isolated stairs are treated differently and only need the compliant nosing strip.
What are the AS 1428.1 stair nosing requirements?
Each tread needs a nosing strip of a single continuous colour, 50 to 75 mm deep, set back no more than 15 mm from the front edge, with at least 30% luminance contrast to the background. If the strip sits right at the edge, it cannot extend more than 10 mm down the riser. The nosing profile itself is also controlled, so check overhangs and sloping risers against clause 11 of AS 1428.1-2009, the edition NSW projects still use until NCC 2025 starts on 1 May 2027.
What handrails does an accessible stair need?
An accessible stair needs a handrail on both sides, set between 865 and 1,000 mm above the nosings, with a round or elliptical grip, at least 50 mm clear of the wall and continuous across landings. The rail must extend past the top and bottom of the flight and end so it cannot catch clothing. These rules come from AS 1428.1 and go further than the NCC's general handrail clause, which only requires one side on narrower stairs.
This page is informational for practitioners. It is not legal advice. Confirm current clause wording in the NCC edition and Australian Standard that apply to your certificate.