Live Rooftop Plant Lifting at 60 Charlotte Street, London

60 Charlotte Street is a mixed commercial and residential building in London's Fitzrovia. The roof insulation was deemed unsafe and needed full replacement before the property could be sold. The problem was the rooftop was packed with live building services plant — air handling units, chillers and air conditioning condensers — all serving occupied spaces below. The heaviest unit was a chiller weighing 2,500kg.

Shutting the plant down wasn't an option. The building's business and residential occupants relied on these systems for heating, cooling and ventilation, and any extended outage would have been unacceptable. Every unit needed to remain wired, gassed and fully operational throughout the works.

The roof works had to be carried out in phases, section by section, which meant plant needed to be temporarily lifted, held clear of the working area while the insulation beneath was stripped and replaced, then set back down — repeatedly, across multiple zones over several weeks. All of this on a central London rooftop with limited space, neighbouring buildings in close proximity, and the usual constraints of working at height on a live site.

We designed and installed scaffold-based runway and gantry lifting systems on the rooftop, purpose-built to allow each piece of plant to be raised clear of the roof surface while remaining connected to its electrical supply, refrigerant pipework and controls. The scaffold structures were engineered to support the plant at height for extended periods while the roofing team worked beneath.

The works were planned in phases to match the roofing contractor's programme. In each phase, we lifted the plant serving that section of roof, held it in position on the gantry system while the old insulation was stripped and new insulation laid, then lowered it back onto its new base. This cycle was repeated across multiple zones until the entire roof was complete.

Careful coordination was essential throughout. The roofing contractor, the building's facilities management team and SLS all needed to work to a shared schedule. Every lift had to account for the live services running to each unit - cables and pipework had to have enough slack and protection to accommodate the temporary repositioning without damage or disconnection. We had to ensure that all plant was fixed and safe whilst suspended in the air.   

Working on a central London rooftop in a mixed-use building also meant managing noise, access and site welfare alongside the technical lifting work. Our team maintained clear communication with building management to minimise disruption to the occupants below.

Every piece of rooftop plant was successfully lifted, held clear, and repositioned across all phases of the roof insulation replacement. Not a single system was taken offline during the works - heating, cooling and ventilation services continued uninterrupted for the building's occupants throughout the entire programme.

The phased approach kept the project on schedule and allowed the roofing contractor to work efficiently beneath the raised plant. The scaffold gantry systems were dismantled on completion, leaving a fully insulated roof with all plant back in its permanent position.