How it is calculated
The wall area (length × height minus openings) is multiplied by the number of sides and layers, plus 5 % for cuts, and divided by the area of one board (1.2 m wide). Studs stand at the chosen spacing plus one at the end; the track runs along the floor and ceiling. Screws are counted at about 25 per square metre of board, which matches the usual 250 mm spacing.
Boards = area × sides × layers × 1.05 ÷ (1.2 × board height)Studs = wall length ÷ spacing + 1Track = 2 × wall lengthExample
A 4 m partition 2.7 m high with one layer on each side needs 7 boards of 1.2 × 2.7 m, 8 studs (21.6 m), 8 m of track and about 540 screws.
Tips from practice
- Choose board height equal to the ceiling height to avoid horizontal joints.
- Use moisture-resistant boards in bathrooms and kitchens.
- Add extra studs around doors and where you will hang cabinets.
Questions and answers
What stud spacing should I use?
600 mm is standard for a single layer of 12.5 mm board. For tiles, heavy loads or thin boards use 400 mm.
How many screws per board?
A 1.2 × 2.7 m board needs roughly 70–80 screws at 250 mm spacing along studs and edges.
Do I need two layers?
Two layers give better sound insulation, strength and fire resistance. One layer is enough for most simple partitions.
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