The 25-year-old external concrete staircase at Kenneth Steel House, serving as the primary four-storey fire escape for Avon & Somerset Police, Bristol, has undergone a complete structural overhaul.

The staircase had been suffering from concrete carbonation – a chemical process where carbon dioxide reduces the concrete’s alkalinity, leading to corrosion and expansion of the embedded steel reinforcement and causing cracking and spalling. Given its role as the primary emergency escape route, the refurbishment had to be carried out while keeping it fully operational.

We implemented a carefully phased 4-week programme, working on one flight at a time, fitting ‘stair boards’ for the stairs we were working on, and coordinating with the client to maintain safe, uninterrupted access at each stage.

Valued at £60,000, the project included breaking out deteriorated concrete, mechanically cleaning corroded rebar, applying a corrosion-inhibiting resin treatment, and re-encasing it using a high-performance Sika repair mortar. We also repaired the aluminium balustrades and the stairwell’s flat roof, applied a durable textured slip-resistant coating to all walking surfaces, and redecorated throughout to restore its professional appearance. The result is a structurally sound, safe, and modernised fire escape that will serve the building for many more years to come.

Compliant with national security protocols, our field-based teams also underwent thorough external security vetting via the National Contractors Vetting Service see earlier article - run by Warwickshire Police for England, Scotland, Wales, and Northern Ireland - which conducts checks on individuals who require access to sensitive and restricted environments, such as police premises, through their work.

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