Metal railings for walls, steps, ramps and boundaries

Heights and gaps: what Approved Document K asks for

Where there is a drop of more than 600 mm at a house, Building Regulations expect guarding. Approved Document K puts the minimum height at 900 mm on stairs, ramps and landings and 1100 mm at the edge of a balcony, roof or raised terrace, measured from the surface people stand on. Where children under five could be about, no gap in the railing should let a 100 mm sphere through, and there should be nothing a child can climb, which rules out horizontal mid rails on most domestic jobs. In practice that means uprights spaced so the clear gap stays under 100 mm and a bottom rail kept low. On commercial premises the heights are much the same but the design loads go up, so we size the bars and posts for each run.

Loads: BS 6180 and why the fixings matter

A railing is only as good as what holds it to the ground. BS 6180 sets the horizontal load a barrier has to take at the top rail: 0.36 kN per metre for a house, 0.74 kN per metre for most commercial floors, and more where crowds gather. That load has to get through the post, into the fixing and into something solid. On concrete or sound brick we use base plates with resin anchors. On a stone coping we core drill and grout the posts in. Where the wall is old and soft we go down past it to a footing, or run a flat bar along the top and fix through it at intervals. For a garden boundary, posts concreted into the ground are the simplest fixing of all.

Step and ramp railings

Outside steps need a handrail on at least one side, and on both sides once the flight is over a metre wide. Handrail height is 900 mm to 1 metre above the pitch line of the steps, and it should be something you can actually grip, so we use a round tube or a shaped flat on top of the guarding rather than a sharp bar. Ramps follow Approved Document M: handrails both sides at 900 mm to 1 metre, a kerb or upstand at the open edge, and rails that run on past the top and bottom by 300 mm on commercial premises. We side fix into the flank of concrete steps, base plate onto the treads, or concrete posts in at the ramp edge, whichever gives the most solid result for your ground.

Period styles: Victorian, Edwardian and estate railings

Many of the railings on London and Kent terraces were cut off for scrap in the war and never put back, and the stubs are often still in the coping. We make replacements the way the originals were made: 40 by 10 flat bar top and bottom rails, 12 or 16 mm square bar uprights, cast or forged spearhead, urn or fleur-de-lis finials, collars where the bars pass through, and a row of short dog bars at the base if the pattern had them. Bow-top railing suits schools and parks; hoop-top and Edwardian panels suit larger houses. Estate railing is the rural boundary type, round bar rails threaded through flat bar posts, made to follow the ground. Send a photo of a surviving original or a neighbour's run and we will draw to match.

Materials and finishes

Mild steel is the right material for nine railings in ten: it takes a galvanised coat, it welds cleanly and it holds a crisp profile on finials and scrolls. For outside work every run is hot-dip galvanised at the plant, then polyester powder coated in a RAL colour; black is traditional, anthracite and dark green are common, and any colour is possible. Galvanising alone gives a plain grey finish that suits a farm boundary or a yard, and the zinc keeps protecting the steel where it gets scratched. Stainless steel, grade 316 for outdoors, suits a modern house and comes brushed or polished, with glass panels between posts where you want the view kept. Paint brushed onto fresh zinc rarely lasts, which is why a powder coat baked on over the zinc is our standard finish.

Survey, price and lead time

Send photos and a rough length and we will put a written estimate together within the working day. The free survey then measures the run properly, checks what the posts will fix into, looks at the levels so the top rail runs true over a sloping wall, and notes anything that affects the drop and therefore the height. You get a drawing and a fixed quotation that only changes if the design changes. Length and height set the base price; bar spacing, finials, scrolls, curved sections, core drilling into stone and matching an existing pattern add to it. Fabrication takes weeks rather than days once the drawing is signed off, with galvanising and coating on top, and fitting a typical domestic run is a day or two on site.

Straight answers on metal railings