Canteen alcove: 18 seats versus an accessible route
Southshore College wants to convert a disused tuck-shop alcove into a student study-and-eat space. The alcove is 4.2 m long × 2.6 m deep with a 2.7 m ceiling. One long wall has a 1.8 m window with a 900 mm sill; the opposite wall is shared with the gym and contains a fire-exit door that must stay clear of obstruction. The property manager's brief asks for seating for 18 students, a clear accessible route from the corridor entrance to the fire exit, power for six devices, and a budget of NZ$6,000. Student designer Hemi's first plan uses four 700 × 700 mm tables with fixed benches on both sides, arranged in a 2 × 2 grid with 900 mm between tables and 700 mm to each wall. The property manager likes it because it reaches 18 seats. The special needs coordinator has asked to see the plan before it goes to the board.
1. Evaluate Hemi's layout against the brief. Identify the conflict and support it with measurements.
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The layout fails on the one requirement that is not negotiable - the accessible route. The plan is only 2.6 m deep, and the tables plus benches occupy about 1.4 m of that depth. With 700 mm to each wall, the leftover circulation is well under the 1.2 m a wheelchair needs as a clear route, and the fire exit is effectively blocked for anyone using a chair or a walking frame. A 900 mm gap between tables is fine for an ambulant student walking sideways but fails as a passing or turning space.
Seat count also doesn't hold up. Eighteen seats need at least 10.8 m of bench edge at 600 mm per person, and this room's usable perimeter is nowhere near that. The plan only 'hits 18' by seating people two-deep on bench runs with no knee clearance and no space to get out - a plan that works on paper at a scale of 1:50 but fails at 1:1.
The judgement is that the brief contains an internal contradiction. Seat count is a wish; the accessible route is a compliance floor. Hemi should report the conflict, not conceal it inside a drawing that appears to satisfy both.
2. Propose a revised layout and recommend what Hemi should say to the property manager.
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Revised layout:
- A continuous bench along the window wall, 600 mm deep, giving about 7 seats with the sill as a backrest line - massed seating where it is brightest.
- One island bench 1.4 × 0.8 m set parallel to the gym wall, with stools on the room side only, giving 4–5 more.
- Keep a 1.2 m clear route running the full 4.2 m length from the corridor door to the fire exit, unobstructed and marked on the plan.
- One end of the island bench at 750 mm height with 800 mm clear knee space, so a wheelchair user sits with the group rather than at a separate 'accessible' table.
- Power in floor-mounted or bench-top trunking along the window wall, kept out of the route.
That yields about 12 seats, 14 at a squeeze, against the brief's 18.
What to tell the property manager: lead with the number and the reason - '12 seats, because the 1.2 m route to the fire exit is required and 18 seats cannot coexist with it in a 4.2 × 2.6 m room.' Offer the alternative: a second alcove, or a bench along the corridor. A designer who brings the constraint and a fallback is easier to approve than one who brings a drawing that quietly breaks the Building Code.
3. What drawing conventions and views should Hemi present to the special needs coordinator to make the circulation argument visible?
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A 1:50 plan is the core drawing, but it must be annotated, not just drawn: overall dimensions, the 1.2 m route shown as a clear corridor with a dimension line and a note ('clear route - no furniture'), bench depths, table heights, and knee clearance under the accessible end.
Add a 1:20 section through the island bench showing 750 mm height, 800 mm clear width and 600 mm knee depth - the coordinator can check that in a second, whereas a plan alone can't show it.
Add a small-scale figure or a plan-view template of a wheelchair footprint (750 × 1200 mm) placed on the plan. It converts an argument into an observation: the viewer sees the fit or sees the clash without needing to trust Hemi's arithmetic.
Conventions matter here: consistent line weights (cut elements heavy, furniture light), a north arrow and scale bar, a title block naming the revision, and a key. Hemi should also show the rejected layout small, labelled 'does not meet route requirement', so the board sees the comparison rather than a single unexplained proposal.