Two Steel Staircases with a Customer Designed Tread Pattern - Purley on Thames

Bespoke external steel staircase with custom pattern cut treads, Purley on Thames

A converted barn style property in Purley on Thames, near Reading, had two external timber staircases that had reached the end of their life. Both were replaced with our galvanised and powdercoated steel staircase with metal railings. The part of the job the customer cared most about was the treads, because he designed the pattern on them himself, and that pattern was then cut into every tread and every landing on both flights.

What we made

Two separate external staircases for the same house, built to the same design so they read as a pair:

A garden side flight rising to the first floor terrace, with its own top landing
A narrower flight in the side passage, serving a first floor door
Steel stringers, treads and landings throughout, with the customer's pattern laser cut into the flat plate before folding
Vertical bar balustrade with decorative forged detail, and a continuous steel handrail
Hot dip galvanised, then powder coated black
Removal and disposal of both existing timber staircases

Get a price for something similar

This is our Galvanised and Powdercoated Steel Staircase with Metal Railings, made to your rise and your opening, with a cut tread pattern as a priced extra.

See prices and options

The customer drew the pattern

Most stair treads get specified rather than designed. You pick chequer plate, or open mesh, or solid plate with a nosing, and the decision is over in a sentence. Here the customer wanted something of his own, so he worked up a flowing leaf and stem motif and we laser cut it into the steel.

It was not applied to the treads afterwards. The pattern is cut right through the tread plate, so what you are looking at is the tread itself with material removed, not a panel sitting on top of one. That matters for how it wears. There is no surface layer to scuff off, chip, or peel in a Berkshire winter, because there is no surface layer.

Each tread starts life as a flat steel plate. The pattern is laser cut into it while it is still flat, and the plate is then folded to form the tread. Doing it in that order is what keeps the pattern crisp and identical from the first tread to the last, and the fold is what turns a cut sheet into something stiff enough to stand on.

Custom pattern laser cut into steel stair treads, providing drainage and anti slip grip on an external staircase — Laser cut right through the plate, not printed or applied to it. You can see the gravel below through the treads.

The same pattern runs across the landings

A pattern that stops at the treads looks like a feature that ran out of budget. The landings were cut to match, so the design carries all the way from the bottom step to the top of the flight. Landings are the largest flat areas on a staircase and they are what you look down on, so they are the place the pattern actually gets seen properly.

Steel staircase landing cut with the same custom pattern as the treads, viewed from above — The top landing, cut with the same pattern so the design runs the full length of the stair.

A cut pattern does three jobs at once

The pattern started as a decorative decision, but cutting it right through the plate brings two practical benefits that a solid tread does not have.

It drains. An external staircase is a horizontal surface sitting outside all year. Rain lands on it, and on a solid plate tread that water has to find an edge to run off. Here it drops straight through. Standing water on a tread is the thing that freezes overnight, so a tread that empties itself is a tread that is less likely to catch you out in January.

It grips. Every cut edge is an edge your shoe can bite on. Across a tread that adds up to a great deal of edge, working in every direction rather than just across the stair the way a single nosing strip does. It is the same principle as open mesh flooring, which is used on industrial access stairs precisely because perforation and grip go together.

It looks like nothing else on the street. Which was the original point.

Why the timber had to come out

Both existing staircases were dark stained timber and both were failing. On the garden side flight the treads had already been replaced once with bare new timber, which is usually the sign that the stair is being kept going rather than maintained. The frames were going the same way.

Timber outdoors is on a clock. It absorbs water, it moves with the seasons, and the places it fails first are exactly the places that matter, which are the tread ends, the stringer housings, and the base of any post sitting in gravel or soil. A steel stair that is galvanised and powder coated does not have that clock running.

The original timber external staircase before replacement, with treads already renewed in bare timber — Before: the garden side timber stair, with pale new treads already fitted into the old dark frame.

Both old staircases were taken out and removed from site by us. That is worth saying plainly, because a replacement stair quote that covers only the new stair leaves the customer standing in a garden with a dismantled timber staircase and no plan for it.

Galvanised first, powder coated second

The finish here is hot dip galvanising followed by powder coating in black. Those are two separate processes and they are doing two different things.

Galvanising is the corrosion protection. The steel goes into molten zinc and the coating bonds metallurgically to it, inside the hollow sections as well as outside, so the protection reaches the places a brush or a spray gun never will. Powder coating on its own is a film sitting on the steel. Scratch it through to bare metal on an external stair and rust starts underneath it and spreads outwards beneath the paint.

Powder coating is the appearance. Galvanising alone is a bright mottled silver that works on an industrial fire escape and looks out of place on a private house. Over the top of galvanising it gives you the colour you want with the protection already underneath it, so a chip in the powder coat exposes zinc rather than steel.

Galvanised and powder coated steel staircase showing the support post and bolted stringer connections — The landing is carried on a steel post, with bolted connections rather than site welding.

You can see the bolted connections in that photograph. Everything that could be made in the workshop was made in the workshop, and what arrived on site was a set of components that went together with fixings. Site welding on a galvanised and powder coated stair means burning off the finish you have just paid for and patching it by hand.

Two staircases, one design

The side passage flight is narrower, steeper and in a far tighter space, hemmed in between the house and a woven screen. It is a different staircase, but it is not a different design. Same tread pattern, same bar balustrade, same handrail, same black finish.

That consistency is easy to get wrong when two stairs are quoted and built as separate jobs. Treated as one project, the second stair simply inherits the decisions already made for the first.

Second external steel staircase in a side passage, matching the patterned treads and bar balustrade of the first — The side passage flight, built to the same design in a much tighter space.

The old timber staircase in the side passage before it was removed and replaced in steel — Before: the side passage timber stair it replaced.

Can you have your own pattern?

Yes. This one was drawn for this house, but there is nothing stopping anyone else asking for the same thing, including asking for this pattern.

Practically, we need artwork we can drive a laser from, which means a clean vector outline rather than a photograph or a scanned sketch. The cutting itself is not the hard part. What makes a pattern work or not work on a stair is the balance of solid to cut area, because the tread still has to carry load, and the size of the openings, because they need to be small enough to be safe underfoot and to stop anything useful falling through.

It is a priced extra rather than a standard option, and the cost depends on the pattern and the number of treads, so it is worth asking rather than assuming. Send us the details and we will price it.

What the regulations ask of an external stair like this

This is a staircase to a private dwelling, so Approved Document K is the reference point. The headline requirements are that guarding to the flight is at least 900mm, guarding to a landing or balcony is at least 1100mm, and no gap anywhere in the guarding allows a 100mm sphere to pass. A handrail sits between 900mm and 1000mm above the pitch line, and the rise and going have to be consistent for the whole flight.

Open riser stairs have one extra condition, which is that the gap between treads must also refuse a 100mm sphere. Because our treads are folded from plate rather than cut from bar, the back of each tread tray folds down and closes that gap, so the stair meets it without separate riser bars running across the flight. It is the single most commonly missed requirement on a replacement external stair, because the old timber one being replaced very often did not meet it.

Our staircase building regulations guide covers the full set, and our note on photographs and building regulations explains why you should not take dimensions off a project photo.

Get a price for something similar

We have been making bespoke steel staircases, balconies and balustrades from our Sheffield workshop for 35+ years, and we deliver and install across the UK. If you have an idea for a tread pattern, or a timber staircase that is on its way out, send us photographs and rough dimensions and we will come back with a price. Email sales@diomet.co.uk or use our contact page.

Steel Staircase with Metal Railings, the staircase on this page
Steel Staircase with Glass Balustrade, the same stair with glass instead of bars
Galvanised Steel Access Staircase, left galvanised for industrial and access use
Galvanised and Powdercoated External Handrail, where only the handrail is being replaced
Metal Railings, to carry the same bar design across a terrace or boundary

If you are not sure what to send us, how to get a price from us sets it out.

Frequently asked questions

Does cutting a pattern into the tread weaken it?
It removes material, so it has to be designed around. The tread thickness, the span and the proportion of solid to open area are all part of that. The fold that forms the tread tray does a lot of the work here, because folding a flat sheet into a tray is what makes it stiff. Even so, a pattern is not dropped onto a standard tread without checking it, which is why we price patterns individually rather than offering them as a tick box.

Will the cut pattern catch heels or stick shoes?
The openings are sized to avoid it. That sizing is one of the things that gets adjusted when a customer's artwork is turned into something cuttable.

Can I have the pattern on the treads but a plain landing?
You can, and it costs less. We would normally suggest matching them, because the landing is the piece you see most.

Do you always remove the old staircase?
Only if it is in the quote. It usually should be. Ask for it to be priced in, along with disposal, so there is no gap between the stair coming out and the new one going in.

How long does a galvanised and powder coated stair last outside?
The galvanising is the part doing the long term work and it is measured in decades rather than years. The powder coat is the part you may eventually want to refresh for appearance. Our material finishes page goes through the options.

Do you work outside Sheffield?
Yes. We are based in Sheffield and work across the UK. This job was in Purley on Thames in West Berkshire.