Project overview
Surespan supplied a combined access and smoke ventilation package for the Canada Water project in London, integrating EXI-VENT roof access/AOV systems with a hydraulically operated flush floor access hatch. The result is a coordinated solution designed around safe maintenance access, smoke ventilation performance and high-capacity floor access in one cohesive specification.
The requirement
Large, mixed-use developments demand access solutions that remain dependable long after handover. At roof level, the project required units that could perform as automated smoke vents while also supporting routine maintenance access without compromising usability. Separately, a flush floor access opening was required to provide a large clear opening, accommodate a recessed infill build-up, and withstand substantial wheel loading for operational activity.
The Surespan solution
Surespan delivered a two-part solution: thermally broken EXI-VENT roof access/AOV units and a Grade 316 stainless steel flush floor access hatch engineered for heavy-duty use.
1) EXI-VENT roof access + AOV systems (thermally broken)
The roof-level solution used large-format EXI-VENT units designed as part access hatch, part AOV, with the two functions separated by an integral fixed rain gutter to support weather management and practical use.
Key performance and usability features included:
- Dual-function configuration: one section dedicated to access and one to AOV performance
- Access section: manual, gas-spring assisted lift with an 85° opening angle for safe roof entry and egress
- AOV section: electrically operated with a 140° opening angle via DC actuator
- Smoke ventilation metrics:
- Geometric free area aligned with Approved Document B design intent
- Aerodynamic free area aligned with EN 12101-2 requirements, with wind deflectors where applicable
- Thermal build-up: insulated lid construction using 50mm PIR insulation, with a quoted U-value of 0.43 W/m²K
- Upstand strategy: insulated upstand detailing with purpose-made flashing and an aluminium curb liner to support common waterproofing interfaces
- Finish: powder coated in RAL 7016 (inside and out) for a consistent architectural appearance
- Handling and installation: removable lifting eyes to support safe positioning on site
2) Hydraulically operated flush floor access hatch (Grade 316 stainless steel)
For floor-level access, Surespan supplied a large, hydraulically operated, double-leaf flush floor hatch designed to provide a substantial clear opening while supporting a recessed infill build-up and demanding operational loads.
Key design features included:
- Large clear opening when fully open, supporting functional access below
- Sequential hydraulic operation of the lids using hydraulic cylinders
- Trolley-mounted manual hand pump and quick connection coupling to support practical site operation
- Recessed pan design to receive a thick infill build-up (e.g., terracotta brick slips installed by others)
- Heavy-duty loading capability: rated for slow moving wheel load up to 5 tonnes
- Durability details: hidden hinge design with EPDM sealing and a satin polish to visible trim/hinges
- Water management: a self-draining design with an integral drainage channel and hose adaptors for connection to drainage by others
Controls and interfaces (AOV package)
To support straightforward operation and commissioning, the AOV package incorporated a complete control and interface set, including:
- OS2 control panel with battery back-up
- Comfort switch (local control)
- Smoke detector and base
- Manual call point / fire switch for life-safety interfacing
This supports clear day-to-day operation for building teams and practical integration with wider fire safety strategies.
Outcome
The Canada Water project received a coordinated access and life-safety package designed for long-term usability across roof and floor interfaces. With thermally broken EXI-VENT units providing smoke ventilation performance alongside practical roof access, and a high-capacity flush floor hatch engineered for heavy-duty loading and recessed infill build-ups, the completed specification supports safe access, robust performance and reliable operation throughout the building lifecycle.
Products used
- EXI-VENT thermally broken roof access + AOV systems
- Hydraulically operated flush floor access hatch (Grade 316 stainless steel)
- AOV controls and interfaces: control panel with battery back-up, comfort switch, smoke detector, and fire switch/MCP
