Aluminium Stair Nosing 2.75m | 90mm Bullnose Twin Insert

This is the 2.75 metre stock length of the heavy duty bullnose stair nosing: a double-channel profile extruded in aluminium alloy at a 5mm gauge, with a 90mm tread plate and a 39mm riser leg. The manufacturer specifies it for medium weight carpet and heavy duty vinyl - the two coverings that take the worst of the wear on a public stair. If you are refurbishing a stairwell that sees hundreds of journeys a day and the edges are already scuffed back to the screed, this is the weight of section that job needs.

Why it works

The gauge does the work

At 5mm, the wall thickness of this extrusion is roughly double that of a domestic stair trim. That matters at the nose, where the load of every descending foot lands on a few millimetres of metal: a thin section deflects, works loose at the fixings, then rattles. The bullnose front is rolled rather than squared, which spreads the contact patch and removes the sharp arris a square edge presents on the way down.

Two channels across a 90mm tread

The double channel puts two parallel bands of PVC insert across the tread instead of one. On a 90mm tread that gives grip across most of the depth a foot actually lands on, and a wider block of colour - which is what makes the step read as an edge from the top of a flight.

Contrast is a specification, not a preference

The manufacturer publishes a Light Reflectance Value for each insert colour and advises a minimum 30-point LRV difference between adjacent surfaces, citing the Equality Act 2010 duty in public buildings and workplaces. That turns insert choice into arithmetic: read the LRV of your floor covering, then pick an insert at least 30 points away from it.

Where it is used

Office and retail stairwells, schools, colleges and university buildings, hospitals and health centres, libraries and community halls, and the shared cores of apartment blocks and student accommodation. It also suits refurbishment work where a previously unprotected concrete or timber edge is being brought up to standard at the same time as a recarpet.

Specifications

Insert colours and published LRV

These figures are the manufacturer's own, from its insert colour chart and its Stair Nosing Insert LRV Data Sheet (rev. January 2022). On-screen colour is for reference only - check a physical sample before committing a specification.

Choosing the right option

Start with the length. Measure the widest step and add an allowance for the saw cut. This 2.75m bar covers most commercial stair widths in one piece; if your steps are wider or narrower, the 2.44m and 3.22m bars are the same profile, listed together on their own page.

Then the insert. Work out the LRV of the finished tread covering and pick an insert at least 30 points clear of it. A dark carpet takes Yellow, White, Oyster, Aura or Sahara; a pale vinyl takes Premium Black, Dark Blue or Dark Grey. Hazard is the banded high-visibility option, kept for plant rooms, loading bays and back-of-house routes.

The finish is a visual decision - the extrusion underneath is the same. Mill Finish is the plain unanodised option, the least expensive, and the one held as standard stock; the anodised finishes are chosen to sit with ironmongery and trims specified elsewhere in the building, and are made to order, so talk to us before committing to one on a deadline.

Installation, use and care

Make good any irregularity in the step with a repair mortar, clean and dry the surface, then dry-fit the nosing and mark through the fixing holes with the profile pushed hard against the riser. On concrete or stone, drill and plug. Apply a cartridge adhesive to the underside, reposition, screw down firmly, then press the insert in to cover the screw heads. The manufacturer asks for weekly cleaning with a mild detergent in water, and warns against polishes, which reduce the anti-slip properties, and against solvents, steam cleaners and power washers.

Frequently asked questions

Is 39mm the tread or the riser?

The riser. The manufacturer gives this profile as tread 90mm by riser 39mm: the 90mm is the plate that sits on the going, the 39mm is the leg covering the vertical face of the step. Some listings for this profile quote 39mm as a tread width, which is wrong - two insert channels plus the rib between them could not fit across 39mm.

Can it be used outside?

The standard PVC insert is an interior specification and no exterior performance data is published for it. The manufacturer makes a separate GRP exterior insert range for external steps, so an outdoor stair should be specified on that basis instead.

Does it carry a slip rating?

No R value or DIN 51130 classification is published for this line. The only slip figure is the pendulum test in the table above, carried out on a linished tread sample rather than a named insert colour. We have not tested it ourselves and make no claim beyond what the manufacturer publishes.

Does the price change with insert colour?

Only for Hazard. Every other insert colour costs the same, so price is set by the metal finish. Hazard is surcharged by the manufacturer per insert channel, and because this is a double-channel profile that surcharge applies twice. It is already built into the Hazard prices shown, so what you see is what you pay.

Can I have it cut to a step width?

These are supplied as full 2.75m stock lengths for cutting on site. Aluminium of this gauge cuts cleanly with a fine-tooth blade in a mitre saw; file the cut end before fitting.

Ordering and delivery

Choose the finish first, then the insert colour: the price for that exact combination is shown before you add it to the basket. Order one bar per step - count the steps rather than measuring the run. The same profile is also stocked in 2.44m and 3.22m.