St Pauls Catholic Primary School, Thames Ditton — mechanical, electrical and alarm services enabling and reinstatement works supporting the installation of structural steel reinforcement to failing RAAC planks. Completed two weeks ahead of programme.
Working inside somebody else’s programme
Reinforced autoclaved aerated concrete (RAAC) has taken a number of school buildings out of use at short notice. Where planks are failing, the remediation is structural — but almost none of it can start until the building services running through the affected areas have been dealt with.
At St Pauls, a building contractor was appointed to install steel reinforcement supporting the failing planks in the school’s corridors. ComGas worked alongside them, responsible for the safe isolation and strip-out of all mechanical and electrical services in the affected areas, and for putting everything back afterwards.
The new steel supports sit approximately 100mm from the load-bearing wall. That dimension governed the whole M&E scope: every service running at high level through those corridors had to be moved clear of it and then returned to service.
Mechanical: heating and domestic water services
- Existing hot and cold domestic water services running at high level within corridors and WCs were isolated and adjusted as necessary to suit the new steel installation
- Existing carbon steel LTHW heating flow and return services were adjusted as required to suit the proposed steel installation
Electrical: containment and wiring
- Existing electrical containment within the corridors was adjusted to suit the installation of the new steel supports
- Wiring was removed or adjusted as necessary to enable the steelwork to be installed
Alarm services
- Existing fire alarm cabling and components within the corridor were adjusted and modified to suit the new steel installation
- Existing intruder alarm cabling and components within the corridor were adjusted and modified to suit the new steel installation
Reinstatement
Following the steelwork, ComGas reinstalled all services to full working order — water services, heating flow and return, electrical containment and wiring, and the fire and intruder alarm systems serving the corridors.
The value of the enabling contractor on a job like this is measured in how little the structural team has to wait. The project completed two weeks early, allowing the main contractor to hand over and the school to return staff and pupils to their classrooms ahead of schedule.
Corridors and classrooms back in use
With the steelwork complete, the corridors and classrooms were handed back with every service working again: heating flow and return, hot and cold water, electrical containment and wiring, and the alarm systems serving the affected areas.
Why this scope needs one contractor
The scope crossed four disciplines — domestic water, heating, electrical, and alarm systems — in the same short stretch of corridor, on the same programme, against the same steel. Split across separate specialists it becomes a coordination exercise with several parties waiting on each other.
ComGas covers mechanical and electrical services under one appointment, which is why this kind of multi-discipline enabling package sits naturally with us. It is a recurring requirement in the education estate as RAAC surveys and remediation programmes continue.
ComGas has also carried out a separate plant room refurbishment at the same school: St Pauls Catholic Primary School — boiler and water heater replacement.
