Aluminium Stair Edge Trim, Pre-Formed Side Angles and Landing Strip

On an open-string staircase, the exposed side of every step is the detail that gives the job away. Floor covering left raw at the string edge frays, lifts and collects dirt within months, and no amount of care with the nosing afterwards will hide it. These pre-formed aluminium stair side angles solve that at the right point in the sequence: they go on before the floor covering and before the stair nosing, giving each step a formed metal edge to be laid up to. The range covers square-front steps at 90 degrees, rake back steps at 83 degrees, and a separate straight landing trim in 2.5m lengths for the flat edge at the head or foot of a flight.

Why it works

The angle is formed, not bent on site

Each angle arrives already formed to the angle between tread and riser, with legs of 350 x 350mm and a depth of 42mm. A trim folded on site rarely holds a consistent line down a flight, and the eye reads the string of a staircase as a single diagonal. A pre-formed angle repeats the same corner on every step, so the run stays straight.

Aluminium takes the traffic the edge actually gets

The exposed side of a step is where trolleys clip, cleaning machines run and feet catch on the turn. Aluminium holds a defined arris under that treatment where a covered or timber edge crushes, and cuts cleanly with a fine-tooth blade, so mitres and butt joints close up rather than leaving a gap that fills with grit.

Fitting first protects the work that follows

Because the trim goes on first, the covering is cut to a solid metal edge instead of a fragile one, and the nosing lands on finished work. Get the order right and replacing the covering later does not disturb the edge detail.

• Pre-formed to 90 degrees for square steps or 83 degrees for rake back steps
• 350 x 350mm legs, 42mm depth, mill aluminium or black coated
• Separate 2.5m landing trim, 42mm face, for flat landing edges
• Fitted before the floor covering and the stair nosing
• Cuts and mitres with standard site tools

Where it's used

Open-string stairs in offices, schools, student accommodation, healthcare buildings and apartment blocks - anywhere a flight has a visible side rather than a wall on both sides. The landing trim suits the flat edge at half-landings and at the head of a flight, and straight side runs where no angle is needed. Both are common on carpet tile and sheet vinyl refurbishments.

Specifications

Choosing the right option

Start with the step profile. Hold a spirit level against the riser: if it sits plumb under the tread, the step is square and you want the 90 degree angle. If the riser leans back so the tread overhangs, it is a rake back step and the 83 degree angle follows it. Getting this wrong leaves a wedge of shadow at every corner.

Then count what you need. The angles are supplied as individual pieces, so order one per exposed step side - two per step where a flight is open both sides. The landing trim comes in straight 2.5m lengths, so measure the edge and allow for cutting waste.

Finish is a matter of the scheme: mill aluminium reads bright and disappears against pale strings, while black coated holds a defined line against light carpet.

Installation, use and care

Set the trims out before any covering goes down. Offer each angle up to the step, mark and cut, then fix with a construction adhesive or mechanical fixings to suit the substrate. Where the covering gauge needs the trim held clear of the deck, dual-height positioning clips are available separately for gauges from 3.5mm to 8mm. Lay the covering up to the fitted trim, then fit the stair nosing over the top. In service, clean with a damp cloth or neutral floor cleaner; avoid abrasive pads on the coated finish.

Frequently asked questions

Is this the same as a stair nosing?
No. A stair nosing protects the front edge of the tread; this trim finishes the exposed side of the step at the string. On most jobs you fit this first and the nosing afterwards.

How do I know whether I need 90 or 83 degrees?
Check whether the riser is plumb or raked. A plumb riser under a square tread takes the 90 degree angle; a raked riser with an overhanging tread takes the 83 degree rake back angle.

What length is each piece?
The angles are pre-formed with 350 x 350mm legs and supplied as individual pieces. The landing trim is a straight 2.5m length.

Can it be used on external steps?
Performance in external conditions is not published for this line, so we do not specify it for outdoor use. Ask us before ordering for an exposed site.

Are the positioning clips included?
No. The dual-height clips that set the trim to the covering gauge are a separate item; tell us the gauge you are working to and we will confirm what you need.

Ordering and delivery

Every option is priced individually above: select the profile, finish and quantity, and the price updates as you go. Orders are picked and despatched from stock. If you are pricing a full flight and want the count checked against your step schedule, send it over and we will work it through.