Basement Switchroom & Mains Upgrade
Following a major power failure caused by floodwater entering a basement switch room, Compass EP was appointed as Principal Contractor to deliver a mains infrastructure upgrade at Fortnum & Mason’s Piccadilly flagship store.
Location: Piccadilly, London
Delivery Role: Principal Contractor
Project Manager: Mace
On-site construction phase: 12 weeks
Delivered within a live trading environment and under strict operational constraints, the project was completed with no impact on customer trading and minimal disruption to back-of-house operations.
Context and Challenge
A floodwater ingress event into the basement switch room triggered a major power failure risk scenario, requiring a robust infrastructure upgrade to restore resilience and future-proof the site. This programme demanded careful phasing and disciplined stakeholder coordination to maintain continuous operations throughout delivery.
Scope of Works
Compass EP delivered a highly complex scope, including:
Construction of two new switch rooms
Installation of approximately 70 linear metres of 2500-amp busbar
Delivery and installation of 15 tonnes of new switchboards
Diversion and rewiring of 60 sub-distribution circuits
Diversion of existing services to facilitate construction works
Temporary power provision via generators to protect critical supplies
Live-Environment Delivery Context
All works were undertaken while the store remained fully operational, requiring close collaboration with the client and careful management around:
Public trading requirements
Back-of-house logistics
Restaurant service hours and guest experience
Private functions and event schedules
Restricted access and egress routes
Particular Project Constraints
Key delivery constraints included:
Live store environment and heightened health and safety controls
Restaurant operating hours: 07:00–00:00
Store logistics window: 04:00–14:00
Private functions and variable on-site stakeholder requirements
Access / egress limitations and sequencing constraints
Structural constraints: floor strengthening required for new panel placement
Critical power needs for frozen and chilled food products
Critical IT infrastructure requiring continuity protection
Generator-backed temporary power required to support critical supplies
Height and space restrictions driving bespoke switchboard design
Off-site storage and logistics requirements
Diversion of existing services to enable construction works
Delivery and Programme Performance
After 18 months of planning to overcome significant coordination and construction constraints, Compass EP completed the on-site construction phase in 12 weeks under the project management oversight of Mace. The programme demonstrates Compass EP’s ability to plan and execute complex infrastructure upgrades in live environments, safely, efficiently, and without disruption to trading operations.
The Result
The completed solution delivered substantial resilience, compliance, and future capacity improvements, including:
A new compliant non-essential mains switch room, complete with fire detection and fire suppression
A new compliant generator-supported essential mains switch room, complete with fire detection and fire suppression
A new fire-rated supply busbar from 11kV transformers to the new switch room (circa 70lm)
Upgraded emergency lighting to areas impacted by the construction of new switch rooms
An automated backup generator PLC providing load shedding and supply monitoring
Future-proofed switchboards designed to accommodate additional load requirements
Outcome
Most importantly, the project achieved a successful migration of power while maintaining full trading operations throughout, reinforcing Compass EP as a trusted delivery partner for mission-critical works in live environments.
Client Comments
“Justin and I caught up yesterday and wanted to recognise your brilliant leadership, expertise and support through the switch room project.” (F&M CFO)
“Thanks again for delivering such a complex and successful project, it is really appreciated and key with have such expert partners alongside us.” (F&M CFO)
“Thanks for the update and I would like to take the opportunity to thank you personally for your commitment and support in delivering this project. A credit to you and Compass as a team in achieving a successful migration of power whilst maintaining full trade to the store over the past 3 weeks.” (Head of Property)