Replacement PVC Insert Strip for Aluminium Stair Nosings, Per Metre

Replacement PVC insert strip for aluminium stair nosings, sold by the linear metre in 15 colours. This is the coloured strip that sits in the channel of the nosing and takes the wear: the part that goes shiny, fades, splits or lifts long before the aluminium does. Replacing it restores the step edge without disturbing the nosing, the floorcovering or the stair itself.

Four sizes cover the standard UK channel dimensions: 50 x 4mm and 50 x 2mm for single-channel nosings, 38 x 4mm and 38 x 2mm for twin-channel nosings. Measure your channel before ordering.

Which size fits my nosing?

Channel width tells you 50mm or 38mm. Channel depth, which follows the gauge of the nosing, tells you 4mm or 2mm.

Twin-channel nosings need two strips. A twin-channel profile has two 38mm channels running side by side with a bare metal rib between them, and both have to be filled. Order twice the length of stair you are covering: a 900mm step needs 1.8m of strip.

How to measure

1. Width. Lift out a short piece of the old strip and measure across the empty channel, lip to lip. It will be close to 50mm or close to 38mm.
2. Depth. Lay a steel rule across the top of the nosing and measure down to the bottom of the channel, or measure the thickness of the old strip. 4mm means a heavy duty profile, 2mm a standard one.
3. Length. Measure the width of one step, multiply by the number of steps, and double it if the nosing is twin channel. Add a little for cutting.

Replacing a worn insert

1. Lift the end of the old strip clear of the lip with a thin flat-bladed screwdriver or putty knife, then pull it back along the step at a shallow angle.
2. Scrape and vacuum the channel. Grit or old adhesive left behind will stop the new strip sitting flat.
3. Cut the new strip a few millimetres shorter than the step width, using a sharp knife against a steel rule or heavy shears.
4. Lay it into the channel at one end and press it home along the step, pushing it under the lip on both edges. A rubber mallet or a timber block helps with 4mm strip.
5. Check that the strip finishes level with the top of the metal along the full width.

No adhesive is needed in a standard dovetail channel. On a flight, do every step at once: a single new strip among worn ones is more obvious than the worn ones were.

Choosing a colour

The insert is the visual edge marking on the stair, so contrast matters more than the shade. Approved Document M and BS 8300 both ask for a step edge that is visually distinguishable from the tread and riser, and the working rule used in specification is a difference of at least 30 points of light reflectance value between the insert and the floorcovering either side of it. A dark strip on a pale floor, or a pale strip on a dark floor, does that. Matching the insert to the carpet looks neat and defeats the purpose.

Screens and lighting shift colour, so treat the photographs as a guide rather than an exact match. If you are matching an existing flight, keep a short offcut of the old strip to compare against.

Specification

• Material: extruded PVC insert strip
• Widths: 50mm (single channel) and 38mm (twin channel)
• Thicknesses: 4mm for heavy duty 5mm-gauge nosings, 2mm for standard 3.5mm-gauge nosings
• Colours: 15, including black-and-yellow Hazard
• Supplied: by the linear metre, in continuous lengths, cut to size on site
• Use: internal stairs. For wet, dusty or heavy-traffic stairs choose a gritted insert, and for external steps choose an exterior gritted insert; both are listed separately

This strip is a replacement part for an aluminium nosing that is already fitted. If the aluminium itself is bent, loose or corroded, or the fixings have pulled out of the step, the nosing needs replacing rather than re-inserting.

Colours

• Premium Black - a deep matt black
• Apple Green - a bright mid green
• Aura - a soft powder blue
• Beige - a warm neutral stone
• Brown - a mid chocolate brown
• Dark Blue - a deep navy
• Dark Green - a deep bottle green
• Dark Grey - a deep charcoal grey
• Hazard - black and yellow
• Mid Grey - a neutral mid grey
• Red - a strong signal red
• Sage Green - a muted grey-green
• Sahara - a warm sand
• White - an off-white
• Yellow - a bright safety yellow

Questions

Which size do I need?

Two measurements decide it. First, measure the width of the empty channel in your nosing: a single-channel nosing takes a 50mm strip, and each channel of a twin-channel nosing takes a 38mm strip. Second, check the depth of the channel, or the thickness of the old strip if you still have a piece of it: heavy duty nosings (5mm gauge) take a 4mm strip, standard nosings (3.5mm gauge) take a 2mm strip. If the old strip has gone and you are unsure, a 4mm strip in a 2mm channel will stand proud and lift at the edges, and a 2mm strip in a 4mm channel will sit below the metal and rattle, so it is worth measuring the channel depth with a steel rule before ordering.

How much do I order for a twin-channel nosing?

Twice the length of the stair. A twin-channel nosing has two separate channels side by side and needs two 38mm strips running the full width of each step. A 900mm step therefore takes 1.8m of strip, not 900mm. Single-channel nosings take one strip, so the metres you order match the metres of nosing.

Can I replace the insert without taking the nosing up?

Yes, on almost every aluminium nosing. The strip is a separate part that sits in a channel in the metal and is held by a dovetail lip along each edge, so the old one lifts out and a new one presses in while the nosing stays screwed to the step. That is the whole point of the design and it is why a worn stair can be brought back to standard in an afternoon rather than being ripped out.

How do I get the old strip out?

Start at one end of the step. Slide a thin flat-bladed screwdriver or a putty knife under the end of the strip and lift it clear of the lip, then pull it back along the step by hand at a shallow angle. It usually comes out in one piece. If the strip has gone brittle and is breaking up, work along it in sections and scrape the channel clean afterwards, because grit or old adhesive left in the channel will stop the new strip seating flat. Vacuum the channel out before you fit.

How do I fit the new strip?

Cut it a few millimetres short of the full step width so it is not fighting the ends, lay it into the channel at one end, and press it home with the heel of your hand working along the step. On a 4mm strip a rubber mallet or a block of timber helps. Push it under the lip on both edges as you go. No adhesive is needed on a standard channel. Finish by checking that the strip is level with the top of the metal along the whole step.

What tools do I need to cut it?

A sharp trimming knife against a steel rule, or a pair of heavy shears, will cut PVC strip cleanly. Score the face first and then bend it back rather than trying to cut through in one pass, which gives a straighter edge. Cut on a board, not on the finished step.

Which colour should I choose?

For safety, contrast is what counts, not the colour itself. Building Regulations Approved Document M and BS 8300 ask for a step edge that stands out visually from the tread and riser, and the usual working rule is a difference of at least 30 points of light reflectance value between the insert and the floorcovering either side of it. In practice that means a dark insert on a pale floor or a pale insert on a dark floor. Matching the insert to the carpet may look tidier, but it removes the edge marking that the nosing exists to provide. Where the stair is a known hazard, Hazard or Yellow is the clearest choice.

Is Hazard the same black and yellow used on safety tape?

It is the same convention: a black and yellow diagonal split that reads as a warning at a glance. It is specified on plant room steps, loading bays, back-of-house stairs and anywhere the step edge needs to be treated as a hazard rather than simply marked. It costs more per metre than the plain colours because of the way the strip is made.

Will this strip make my stairs slip resistant?

The strip is the wearing surface your foot lands on, so replacing a worn, polished or missing insert restores the grip the nosing was installed to give. A smooth PVC strip is the standard internal specification. Where the stair gets wet, dusty or very heavy traffic, a gritted insert gives more bite than smooth PVC, and for external steps a gritted exterior insert is the right specification. We list both of those separately.

How long does an insert last?

On a normal internal commercial stair, years. What kills an insert early is grit tracked in from outside, wheeled traffic and cleaning chemicals, all of which abrade or bleach the surface. The visible signs that it is due for replacement are a polished shine on the walking line, the colour washing out, the strip lifting at the ends, or the metal lip showing through. Replacing the strip is far cheaper than replacing the nosing, and on a flight it is worth doing every step at once so the stair looks even.

Does the strip come in one continuous piece?

Yes. Order the total number of metres you need and we supply it as continuous lengths for you to cut on site, rather than pre-cut pieces. That way you choose where the joins fall, which matters on a stair where every step is the same width.

Will this fit a nosing from another manufacturer?

Very often, yes, because 50mm and 38mm channels at 2mm and 4mm depth are the common sizes across UK aluminium nosings. It is not guaranteed, though, as channel profiles and dovetail lips vary. Measure the channel width and depth of your existing nosing and compare them with the four sizes above. If the measurements sit between our sizes, the nosing is a non-standard profile and the strip will not seat properly.