What the Furniture Space Calculator actually calculates
Furniture footprint is item length times item width times quantity. The tool divides that sum by room area for occupancy and subtracts it for free floor, clamped at zero. Multiplying independently averaged lengths and widths may misrepresent mixed furniture sizes; the calculation also cannot detect overlapping items or disconnected free space.
The calculation path
The quantity-weighted furniture footprint is divided by room area to calculate occupancy.
Inputs that can change the answer
- Room length: Enter room length in m.
- Room width: Enter room width in m.
- Average item length: Enter average item length in m.
- Average item width: Enter average item width in m.
- Number of items: Enter number of items as a number; use the definition in the calculation method.
Checks that stay outside the formula
Aim to preserve continuous circulation paths rather than isolated pockets of free space.
A practical order for entering the data
- Enter the room length and width in metres.
- Enter the footprint dimensions and count for identical furniture pieces, or an area-equivalent representative item.
- Compare occupancy and unoccupied floor area, then check actual walking routes on a plan.
Engine check using the prefilled sample
Worked example: room length = 5 m, room width = 4 m, average item length = 1.8 m, average item width = 0.85 m and number of items = 3. Replace the sample dimensions with measurements from the room; split irregular areas into simpler sections where needed.
Results for these inputs
- Room area
- 20.00 m²
- Furniture footprint
- 4.59 m²
- Unoccupied floor
- 15.41 m²
- Floor occupancy
- 22.95 %