For most homes and small commercial buildings in Kent, Surrey and South London, the right external staircase is a mild steel flight, hot-dip galvanised, then powder coated, with a layout chosen to suit three things: the height it has to climb, the ground it has to land on and the job it has to do. A straight flight suits a site with room to spare, a flight with a landing folds back where a straight run would reach too far, a spiral fits the tightest footprint, and a fire escape has to satisfy Approved Document B as well as Approved Document K.
Begin with the job the stair has to do
Before thinking about treads or colours, be clear about who will use the staircase and how often. A stair serving a flat above a shop is a front door, so it needs a comfortable going and a landing with room to put shopping down. A garden stair from a first-floor kitchen is used less often, so appearance matters more. An escape stair is designed for people in a hurry in the dark. A landlord splitting a house into flats needs a separate entrance, which is a Building Regulations job and usually a planning job too.
The main layouts and where each one works
Straight flights
A straight flight is the simplest to fabricate and the easiest to use. The limit is length. Climbing a full storey takes around fifteen or sixteen risers, and at a comfortable going the flight stretches more than three metres along the ground before the foot and handrail are added.
Flights with a landing
Where a straight run would reach too far, a quarter landing turns the stair through ninety degrees and a half landing turns it back against the wall. Both keep the footprint close to the building and let the stair arrive square to the door.
Spiral staircases
A spiral staircase climbs a full storey inside a circle of around two metres, which makes it the usual answer for a rear extension, a small courtyard or a narrow yard. Bulky items are awkward to carry, and the regulations set their own limits on tread width for spirals, so size it for how it will be used.
Fire escape staircases
A fire escape staircase looks similar to an access stair but is built to a stricter brief. It usually needs to be wider, to have a landing at every change of direction, to discharge to a place of safety away from the building and to be kept clear of windows and doors that could let fire out onto the route.
Materials and finishes that survive outdoors
An outdoor staircase lives in rain, frost and salt from gritted paths, and on higher ground such as Westerham Hill it takes plenty of wind as well. Mild steel is strong, easily welded and takes a durable finish, but left bare it will rust, so the finish is never an afterthought.
Hot-dip galvanising means the finished steelwork is dipped in molten zinc after fabrication. The zinc bonds to the steel and coats every weld, cut edge and the inside of hollow sections, which paint can never reach. Powder coating over the galvanising adds colour in any RAL shade and a second barrier against the weather. Galvanised and powder coated is the standard specification for the external staircases Steel Stairs and Gates makes. Stainless steel suits handrails where a bright finish is wanted. Treads should shed water rather than hold it, and infill to the balustrade can be steel bars, glass or timber, usually chosen to match what is already on the house.
Guarding, handrails and the regulations
Approved Document K sets the guarding height for a domestic stair at 900 mm inside the building and 1100 mm outside, with gaps small enough that a 100 mm ball cannot get through. Risers should be equal all the way up, and a handrail is needed on at least one side, or both sides on a flight a metre or more wide.
Building Control is usually involved for a stair serving a habitable floor, and the inspector will want scaled drawings and, for anything beyond a simple flight, structural calculations showing that the stair, its fixings and its foundation can carry the load. Steel Stairs and Gates produces both where needed as part of the design.
Planning permission is a separate question. In a conservation area or on a listed building, an external staircase will need consent. Elsewhere, a stair that overlooks a neighbour's garden or sits on the front of a house can still need an application, so check with the local authority before any steel is ordered.
What a site survey settles
A photograph and a rough height are enough for an estimate. Fabrication needs more. A free site survey measures the exact drop from threshold to finished ground, checks whether the ground is level, looks at what the stair will fix to and whether the wall will take it, and considers drainage so the foot of the stair does not stand in a puddle.
How the process works
- Send a photo and the approximate height to 07861 936 888 or info@steelstairsandgates.co.uk for a written estimate the same working day. Someone picks up the phone at any hour.
- Book a free site survey. The team works from 4 Fort Cottages on Westerham Hill and covers Kent, Surrey, South London and everywhere within ten miles of Warlingham, including Biggin Hill, Bromley, Croydon and Orpington.
- Receive scaled drawings, structural calculations where needed and a fixed quotation.
- The stair is fabricated, galvanised and powder coated, then installed by the same team that designed it.
The decisions that matter are made before any steel is cut. Send a photograph of the wall and the ground beneath it to 07861 936 888, or use the quote form, and Steel Stairs and Gates will send a written estimate the same working day.