Fixed ladders and cat ladders for roof access

Cat ladders for roof access

A cat ladder is a fixed ladder pitched between 75 degrees and vertical, bolted to the face of a building to reach a flat roof, a plant area or a tank. We build them to size from mild steel, with solid rungs welded into the stiles, and hot-dip galvanise them. Where the ladder is on show or gets hosed down we make it in stainless. The stiles carry on at least 1100 mm past the roof edge so you have something to hold as you step off, and where the ladder lands inside a guardrail we fit a self-closing gate. That guardrail is designed to the loadings in BS 6180. Rungs go in at equal centres between 225 and 300 mm, with at least 200 mm clear behind each one so your foot goes fully on.

Caged ladders and safety hoops

Once a ladder climbs more than a few metres you need something to stop a fall. BS 4211 is the British Standard for permanently fixed ladders, and it is what anyone inspecting the ladder will measure it against. The normal answer is a cage of steel hoops and straps welded to the stiles. The bottom hoop sits between 2.2 and 3 metres above the ground so nobody walks into it, and the hoops carry on up past the landing. On a climb of more than 6 metres the ladder is broken with a rest platform. Where a cage will not fit, a vertical fall-arrest rail with a sliding shuttle is the neater option, and we can build the ladder to take one. Tell us who will use the ladder and how often, and we will quote the right one.

Ship ladders and steep stairs

A ship ladder, or companionway, is pitched at about 60 to 75 degrees and has flat treads rather than rungs, so you can climb facing forward with a load. It suits a mezzanine, a plant deck or a loft where a normal stair will not fit but a vertical ladder is too awkward. Ours are usually 500 to 600 mm wide with a handrail each side, treads in chequer plate or open mesh never less than 100 mm deep, and a rise of 225 to 250 mm. Approved Document K limits where a fixed ladder or steep stair can be used in a house: in a loft conversion it may serve one room only, with handrails both sides, and only where there is no room for a proper stair. We check this at the survey before drawing anything.

Fixing the ladder to the building

The fixings matter as much as the steel. On brick or block we use resin anchors into the body of the wall, never into a mortar joint. On profiled cladding we fix through to the sheeting rails or the steel frame behind, not to the sheet. On a timber-framed wall we bolt through to the studs with a spreader plate on the inside. The feet stand on a concrete pad or a bolted steel base plate so the ladder cannot kick out. At the top the stiles are bracketed to the parapet, the kerb or a roof upstand and sealed against leaks. The survey checks all of this, where the ladder passes windows, pipes and cable trays, and whether it needs a lockable guard at the bottom to keep the public off it.

Finish, price and lead time

Every mild steel ladder for outside leaves us hot-dip galvanised. If you want a colour it is powder coated over the galvanising; stainless is brushed or polished. Finishing is done at trusted plants, and that round trip adds days, so we give you a realistic lead time with the quotation. The price comes down to height, whether it needs a cage or a rest platform, the material, and how we get at the wall: a ladder reached from a tower costs less than one that needs a platform lift. A ladder up the back of a warehouse in Croydon is a different job to one on a house in Oxted. Send photos with a rough height and you will have an estimate within the working day. The survey is free and the quotation holds unless the design changes.

Straight answers on ladders