Why slip resistance matters
Slip resistance on timber floors is controlled by the coating, not the timber itself. A freshly coated timber floor can be dangerously slippery when wet -- particularly on stairs. The National Construction Code (NCC) mandates minimum slip resistance ratings on all internal and external stairs in Australian buildings, and building certifiers increasingly require test certificates before issuing occupancy permits.
This guide covers the Australian standards, NCC requirements, available anti-slip coatings, how they're tested, and where to get certificates.
Australian standards for slip resistance
AS/NZS 4586:2013 -- Classification of new surfaces
The primary standard. Classifies pedestrian surface materials using three test methods:
- Wet pendulum test (Appendix A) -- a swinging arm with a wet rubber slider measures dynamic friction. Results classified P0 to P5. Most common test for timber floor coatings. Can be done in-lab and on-site.
- Oil-wet inclined ramp test (Appendix D) -- a person walks on a tilted, oil-lubricated surface. Results classified R9 to R13. Used for kitchens, food processing, and areas with grease contamination.
- Wet barefoot ramp test (Appendix B) -- for pool surrounds, showers, and barefoot areas. Classified A, B, or C.
AS/NZS 4663:2013 -- Testing existing surfaces
Covers in-situ slip resistance measurement of installed floors using the wet pendulum. Used for post-installation verification and compliance certificates.
HB 198:2019 -- Guidance handbook
Non-mandatory guide to floor coverings, finishes, and slip resistance. Complements AS/NZS 4586 with practical advice for specifiers and contractors.
P and R rating scale
| P class | PTV range | Slip risk | Typical use |
|---|---|---|---|
| P0 | <12 | Very high | Not suitable for pedestrian areas |
| P1 | 12-19 | High | Dry internal only |
| P2 | 20-24 | Moderate | Dry internal, low traffic |
| P3 | 25-34 | Low-moderate | Domestic stairs (tread), general commercial |
| P4 | 35-44 | Low | Stair nosings, ramps, wet areas |
| P5 | 45+ | Very low | External wet areas, pool surrounds |
| R class | COF range | Approx P equiv | Use |
|---|---|---|---|
| R9 | <0.38 | ~P2 | Dry areas only |
| R10 | 0.38-0.42 | ~P3 | General stairs/ramps |
| R11 | 0.43-0.49 | ~P4 | Nosings, commercial ramps |
| R12 | 0.50-0.54 | ~P4-P5 | Wet commercial |
| R13 | 0.55+ | ~P5 | Oil/grease areas |
NCC requirements for stairs and ramps
The National Construction Code (BCA Volumes 1 and 2) references AS/NZS 4586 for stairway slip resistance:
| Location | Minimum rating | Applies to |
|---|---|---|
| Stair treads and landings | P3 or R10 | All Class 1-9 buildings |
| Stair nosings and landing edges | P4 or R11 | All Class 1-9 buildings |
| Ramps (Class 2-9) | P4 or R11 | Commercial, multi-res |
| External wet areas | P4-P5 recommended | Pools, decks, walkways |
Key point for floor sanders: Most standard coatings (Bona Traffic HD, Mega, solvent poly) achieve P3 on smooth timber treads. But stair nosings need P4 -- requiring either an anti-slip coating or a physical nosing strip.
Anti-slip coating products -- all brands
| Product | Rating | Cert? | Notes |
|---|---|---|---|
| Bona Traffic HD Anti-Slip | P4 | Yes | Same durability as standard Traffic HD. Minimal visual change in satin. Industry standard for commercial stairs. |
| Intergrain UltraFloor SlipResistant | P5 (3 coats) | Claimed | Exceeds P4. Solvent-based. Heavy-duty for external and high-risk areas. |
| Synteko Nova Best Anti-Slip | R10 | Claimed | Water-based. R10 ~ P3. Treads only, not nosings. |
| Stellmann Non-Slip Clear | P3 | Yes | Independently tested. P3 only -- treads, not nosings. |
| Generic anti-slip additive | P3-P5 | Varies | Aluminium oxide / glass bead / polymer mixed into any polyurethane. Result depends on concentration. Not factory-controlled. |
| Resene Qristal ClearFloor + Grip | Unrated | No | Increased grip, no P/R class published. |
| Polycure / Loba / Pallmann / Feast Watson | -- | -- | No dedicated anti-slip timber variants currently published in Australia. |
Recommendation: For commercial stairs requiring P4, use Bona Traffic HD Anti-Slip -- the only product with a publicly available AS 4586:2013 test certificate at P4, compatible with the Bona system most floor sanders already run.
Getting a slip resistance test certificate
Building certifiers may require a formal certificate for commercial stairs, aged care, schools, and hospitality. Certificates must come from a NATA-accredited laboratory.
| Lab | Location | On-site? | Contact |
|---|---|---|---|
| Safe Environments (SlipCheck) | Sydney NSW | Yes | safeenvironments.com.au |
| Sliptest Australia | Multiple (3 labs) | Yes | sliptest.com.au |
| Stone Initiatives | Adelaide SA | Yes | stonemtg.com.au |
| Zerofal | Australia-wide | Lab only | zerofal.com.au |
| Australian Slip Testing | Logan QLD | Yes | Direct enquiry |
Typical cost: $300-600 per on-site visit. Request testing to AS/NZS 4663 (existing surfaces) or AS/NZS 4586 (new samples).
Practical advice for floor sanders
- Confirm stair requirements before quoting. Ask the builder or certifier whether they need a slip test certificate. If yes, quote Bona Traffic HD Anti-Slip and factor in $400-600 for testing.
- Nosings are the critical zone. Treads need P3 (most coatings pass). Nosings need P4 (most standard coatings fail). Use anti-slip coating on at least the nosing area, or install aluminium/rubber nosing strips.
- Don't use generic additive on commercial jobs without testing. The P rating depends on concentration and application consistency. Factory-formulated products are batch-controlled.
- Keep the certificate on file. If a slip incident occurs years later, the certificate proves the floor met the standard at installation. Professional indemnity protection.
- Re-coating doesn't reset the clock. Anti-slip additive is embedded in the film. When the coating wears through, slip resistance drops. Re-coat before bare timber shows in traffic zones.
Certificates, standards and resources
Test certificates
Australian standards
Find a NATA-accredited slip testing lab
- NATA accredited organisation search -- search "slip resistance" to find accredited labs near you