A drywall partition is a system of boards, framing and fixings. The Drywall calculator distinguishes geometric wall area from the area actually boarded.
A 4 × 2.5 m partition is 10 m² per face. A 0.90 × 2.04 m door removes about 1.84 m², leaving 8.16 m² per face. Two faces therefore need 16.32 m² before allowance. With 10%, that is about 17.95 m².
A 1.20 × 2.50 m board covers 3 m², but a real layout may need more boards because offcuts are not always reusable.
Faces, layers and framing
Two faces and two layers are different parameters. A partition boarded on both sides with two layers per side can require four times the net area of one face.
Stud spacing changes the number of vertical profiles. Use the spacing required by the chosen construction system rather than selecting a larger spacing simply to reduce material.
Openings reduce board area but may require additional framing or reinforcement. Rails, studs and screws are therefore useful estimates, not a complete bill of materials.
For insulation inside the partition use the Insulation calculator. For finishing use the Paint calculator. A masonry alternative can be estimated with the Concrete block calculator.
Before ordering, define the wall system, subtract openings, set faces and layers, enter the actual board format and add a reasonable cutting allowance.