Intro
In this enquiry, a university is converting a small teaching space into a wheelchair-accessible laboratory adjacent to a lecture theatre. The site is compact, multi-level and circulation-sensitive. The brief: deliver step-free access without compromising the usable room area or escape strategy.
The Challenge
Everything is tight. The stair flight is roughly 2070 mm wall-to-wall,
with handrails both sides and a total rise of ~329–350 mm to overcome. Ramp options proved impractical (circa 5.6 m at 1:16), and a traditional platform lift with separate steps risked reducing effective width. The client also needed a 1500 mm wheelchair turning circle on the upper level and a solution that respects the building’s escape philosophy (this route is ancillary/tertiary, not the primary theatre egress).
Space efficiency: With 2070 mm overall, handrail gaps allowed, and a 1057 mm platform, the scheme preserves ~800 mm of clear width during lift operation—aligned with the client’s tertiary-route intent (subject to fire engineer acceptance).
Maneuvering room: ~1.4–1.475 m setup from the top step riser supports a 1500 mm turning circle on the lab level.
Buildability & programme: A compatible stock unit can be adapted to the required rise, materially reducing lead time compared with a fully bespoke build.
Why This Matters
Retrofitting accessibility into dense education spaces is hard: every millimetre affects circulation, capacity and pedagogy. In this case, a narrow, low-rise stair could have forced either a long ramp that ate the room, or a bulkier lift that throttled the corridor. A hidden platform lift protects day-to-day movement, supports dignified independent use, and aligns with stakeholder concerns (fire engineering, user training, facilities) without sacrificing the lab’s usable area.
Q&A
Q1: Will fire officers accept reduced width when the lift is in use?
This corridor is intended as a tertiary route (not the primary theatre egress). With ~800 mm residual width during operation and the lift parked flush when not in use, acceptance typically hinges on occupancy calculations and the fire engineer’s judgement. The team agreed to consult Building Control and fire engineering early.
Q2: How much space is needed at the top step riser?
Plan for ~1400–1475 mm from the top step riser to provide safe access and a 1500 mm turning circle, while keeping clear of adjacent door swings (target ~300 mm offset).
Q3: What are the pit requirements?
The side section indicates a pit depth ~547 mm with ~840 mm behind the top step riser and ~1475 mm forward; an internal sump isn’t required here. Structural checks around party walls/foundations are still prudent.
Q4: Controls and user experience?
Key-controlled user fob for up/down, call stations at both landings, and an optional removable handheld post for hand-hold compliance—kept in a cupboard to maintain a clean aesthetic. An alert prompts staff/users if steps aren’t retracted after use.