A stair nosing is a profile fixed along the front edge of a step. It protects the most heavily worn part of the staircase, puts a slip-resistant surface where the foot actually lands, and marks the edge clearly enough to be judged at a glance.
Most of what is written about stair nosings blurs the line between what the law requires and what a British Standard recommends. This guide keeps them separate, because on a specification that distinction is the difference between a defensible decision and an expensive one.
What a stair nosing actually does
Edge protection. The front 40mm or so of a tread takes the most concentrated wear on any staircase. Unprotected, timber splinters, concrete spalls and tile chips — and a broken edge becomes the trip hazard the stair was built to avoid.
Slip resistance. Grip comes from an insert or a bonded aggregate, not from the body of the profile. This is the part that wears and, on most systems, the part you can replace.
Edge definition. Most stair falls happen on descent, and most happen because the edge was misread rather than because it was slippery. A contrasting nosing tells the eye where each step ends. Grip and contrast matter equally, and contrast is the one people forget.
What UK rules actually require
Four separate things get quoted as though they were interchangeable. They are not.
What is law
The Workplace (Health, Safety and Welfare) Regulations 1992, regulation 12. Every floor and traffic route in a workplace must be of suitable construction and must not be slippery so as to expose anyone to a risk to their health or safety. This is the duty that actually bites, and it applies to the stair as it is today, not as it was on the day it was built.
The Building Regulations, via the Approved Documents, where you are building new or carrying out a material alteration.
What is guidance
Approved Document K covers stair geometry — going, rise, and how far a nosing may project over the tread below, for which 25mm is the figure to work to.
Approved Document M covers access. It is the source of the 55mm × 55mm contrasting band across tread and riser, and it applies to buildings other than dwellings. If you take one dimension away from this guide, take that one.
What is a standard, not law
BS 8300-2:2018 is referenced by Part M but is not legislation. It defines adequate visual contrast as a difference of at least 30 points of Light Reflectance Value between the nosing and the surrounding tread. Ask suppliers for the LRV figure — two colours that look different to the eye can measure very close.
The Equality Act 2010 creates a duty to make reasonable adjustments. It does not itself specify stair nosings, and it replaced the Disability Discrimination Act — so "DDA compliant" is trade shorthand rather than a current legal test.
How slip resistance is measured
Two numbers circulate, and they do not convert into one another.
| Pendulum Test Value | R rating | |
|---|---|---|
| Standard | BS 7976, now BS EN 16165 | DIN 51130 |
| Contaminant | Water | Motor oil |
| Footwear | Rubber slider | Safety boots |
| Test in situ | Yes | No, lab only |
| HSE recognised | Yes, the preferred method | No |
The HSE benchmark is PTV 36 or above in the wet: 0–24 is high slip potential, 25–35 moderate, 36 and above low. Specify 65 or above where oil, grease or food waste is likely.
A single R10 rating can correspond to pendulum results anywhere from 20 to 60 — the whole range from dangerous to safe. Treat a supplier who can only quote an R rating as having answered half the question.
A defensible non-domestic specification therefore reads: a 55mm × 55mm profile, clearing 30 LRV points against the tread, achieving at least 36 PTV wet.
Materials compared
| Material | Wet grip | Corrosion | Appearance | Best for |
|---|---|---|---|---|
| Aluminium | Good, via inserts | Excellent | Wide, anodised or coated | General commercial and domestic |
| GRP | Excellent, 65–80+ PTV | Excellent | Functional only | External, industrial, marine |
| Stainless steel | Depends on finish | Excellent | Industrial, premium | Heavy duty, hygiene-critical |
| Brass | Moderate | Good | Premium, patinates | Heritage, hotel, retail |
| Rubber and PVC | Good, falls with wear | Poor under UV | Limited | Budget, indoor, curved steps |
Aluminium is the default for good reason: corrosion resistant, available in every profile shape and finish, and the insert is replaceable. See the aluminium stair nosing guide.
GRP has the highest wet grip of the common materials and is unaffected by salt or chemicals, which makes it the answer for external, marine and wash-down stairs. See the GRP guide.
Rubber and PVC are cheap and quiet underfoot but degrade under UV, so keep them indoors.
Profile shapes
- Square or straight edge — full vertical face, protects tread and riser. The standard commercial profile.
- Rakeback — the vertical face angles back under the tread. Suits stairs with an existing raked riser and reads as less bulky from below.
- Bullnose — rounded leading edge. Softens a sharp corner, wears evenly, common in refurbishment, care homes and hotels.
- Tile-in — a thin leg beds into tile adhesive so the nose finishes flush with a tiled tread. Specify by tile thickness.
- Push-in and channel — captures the edge of a thin covering such as LVT or laminate. See the vinyl and LVT guide.
- Illuminated — carries an LED strip. Escape routes, cinemas, stepped seating.
- Tread covers — not a nosing at all but a full-width sheet, for stairs where the tread surface itself has failed.
Sizing and gauge
Width — the part sitting on the tread — is the main decision:
- 20–36mm — slim profiles for LVT, thin tile, domestic stairs where bulk matters
- 30–40mm — general residential
- 50–70mm — commercial and high traffic
- 55mm — the Part M figure, on both tread and riser, for non-domestic buildings
- 70–100mm — industrial and retrofit over damaged edges
Gauge is the metal thickness, and it is what separates a profile that survives trolley traffic from one that dishes under it: 1.5mm for light domestic duty, 2.5–3mm for general commercial, 5mm for industrial stairs.
Stock lengths generally run 2.4m to 3.22m and are cut on site. Measure every step individually — flight widths commonly vary by several millimetres in older buildings — and leave 2 to 3mm clearance at each end for thermal movement.
Grip, inserts and contrast
The insert does the gripping. Carborundum and silicon carbide are the hardest wearing; PVC is the commercial default and easy to clean; rubber is softer and better underfoot in barefoot areas; GRP carries its aggregate through the body so grip survives as the surface wears.
On contrast, the cheapest safety improvement available is choosing a nosing colour that differs sharply from the tread. Yellow for hazard areas and loading bays, black against pale concrete, white in healthcare and food production. Photoluminescent profiles charge from ambient light and glow after it goes out, with no wiring, which suits escape routes and heritage buildings.
Which nosing for which setting
- Offices and retail — anodised aluminium, 50–55mm, PVC insert, contrasting colour. Browse commercial stair nosings.
- Schools and hospitals — heavier gauge, Part M band, high contrast, replaceable inserts
- External steps and fire escapes — GRP or marine-grade aluminium, stainless A4 fixings, drainage considered
- Warehouses and plant — heavyweight profiles at 5mm gauge, coarse grit
- Pools and changing rooms — GRP with fine grit, which grips wet without being abrasive to bare feet
- Domestic — slim aluminium or push-in profiles matched to the floor covering
Installation in outline
Screw fixing is the default for concrete, timber and steel, and for anything commercial, external or carrying wheeled traffic. Adhesive suits smooth, sound, dry indoor substrates where fixings must be invisible — but it needs the substrate below about 4% moisture content and above 5°C to cure, which rules out most winter external work.
Space fixings at roughly 150mm centres on concrete, never fewer than three per step, always one near each end, and keep them out of the centre wear line. Tighten to flush plus about a quarter turn; over-torquing dishes aluminium and cracks GRP.
The full method, including substrate preparation, cutting by material and the mistakes that cause callbacks, is in our step-by-step installation guide.
Maintenance and service life
Clean to suit the traffic — weekly in a busy public stairwell, monthly domestically. Keep polish and wax off the inserts, which is the fastest way to undo the slip resistance you specified. Check fixings annually.
On service life, separate the components, because quoting one number for a two-part product is what makes published figures contradict each other:
- Anodised aluminium extrusion — twenty years or more in commercial service
- The insert — the wear part, typically ten to fifteen years, sooner in heavy public use
- GRP — a single piece, guaranteed ten years across our range and routinely beyond that indoors
Where slip risk has been formally assessed, a periodic in-situ pendulum test is how you evidence that the stair still performs rather than assuming it does.
Frequently asked questions
Are stair nosings a legal requirement in the UK?
Not as a standalone product requirement. What is legally binding is regulation 12 of the Workplace (Health, Safety and Welfare) Regulations 1992, which requires that floors are not slippery so as to expose anyone to risk, and the Building Regulations where you are building or materially altering. Approved Document M sets the 55mm × 55mm contrasting band for non-domestic buildings. A nosing is the usual way of satisfying those, not a separate obligation.
What does "DDA compliant" mean?
It is trade shorthand, not a legal standard. The Disability Discrimination Act was replaced by the Equality Act 2010. In practice what applies is Approved Document M plus the Equality Act duty to make reasonable adjustments.
What PTV should I specify?
At least 36 in the wet, which is the HSE benchmark for low slip potential, and 65 or above where contamination is likely. Dry figures tell you very little because almost every surface passes dry.
How wide should a stair nosing be?
30–40mm suits most domestic stairs and 50–70mm most commercial ones. Where Approved Document M applies, work to 55mm on both tread and riser. Never choose a width that leaves an uncomfortably shallow walking surface behind it.
Can nosings be fitted to existing stairs?
Yes — retrofit is the normal case rather than the exception, provided the step edge is sound enough to hold a fixing. Where the edge is crumbling, repair it first; a nosing is edge protection, not a structural repair.
Which material should I choose?
Aluminium for general indoor commercial and domestic work, GRP for anything external, industrial or regularly wet, stainless for heavy-duty and hygiene-critical settings, brass where appearance leads. Environment decides it more than budget does.
Where to start
Four questions settle most specifications: what is the environment, how heavy is the traffic, does Part M apply, and what is the stair finished in. Those decide material, width, gauge and fixing between them.
Browse the full stair nosing range by material, profile and width, or send us the step dimensions, the covering and the setting and we will specify against them.