Property / Whole-house area
Every floor. One clear total.
Measure irregular floors, record deductions and combine units accurately.
Whole-house floor area
Build each floor from non-overlapping sections. Add every storey separately; totals convert all measurements to a common unit.
Measure horizontally to the inside face of the external walls. Split an L-shaped or irregular floor into rectangles and triangles that do not overlap. This approach includes internal walls within your measured outline.
Use one approach consistently across the house. Switching the approach changes the description, not your measurements. Record your treatment of stairs, voids, low ceilings, garages and outbuildings below; their inclusion depends on the purpose and measurement standard.
Ground floor: Enter both dimensions for every section. Complete this floor before viewing the house total.
Check the dimensions against a sketch: the calculator cannot detect overlapping sections, missed spaces or inaccurate measurements. For triangles, use the horizontal perpendicular height, not a sloping side. Decimal feet: 10 ft 6 in = 10.5 ft. Measurements stay in the unit entered when a unit is changed.
This is a measured-area worksheet; it does not certify compliance with a survey standard. RICS measurement guidance. Entries are held on this page only; copy your measurements before leaving or reloading.
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