How the calculation works
The formulas
The table is centred and aligned to the room. Chair projection is measured outward from the table edge, so clearance behind a chair is smaller than table-edge clearance. The desired gap is your own planning target.
End clearance = (room length − table length) / 2
Side clearance = (room width − table width) / 2
Behind-chair clearance = table-edge clearance − chair projection
Assumptions to check
- Doors, other furniture, wheelchair manoeuvring, and local access requirements need separate review.
- For a round table, the diagram uses its diameter and a uniform chair projection.
A worked example
A 1.8 × 0.9 m table in a 5 × 4 m room leaves 1.6 m at the ends and 1.55 m at the sides. With 0.5 m chair projection, behind-chair gaps are 1.1 m and 1.05 m.