Lay boards out
Example: a 5 m × 4 m room is 20 m². A 3,000 × 1,200 mm board layout needs 8 whole boards before allowance; 10% makes 9 boards. The same pass estimates 15 × 3.6 m brandering lengths and 7 × 3 m cornice lengths.
Free South African ceiling-board calculator
Ceiling calculator.
Lay out every board.
Estimate RhinoBoard or gypsum sheets, steel brandering, cornice, screws, cover strip or tape and skim-plaster quantities for rectangular rooms.
Start calculating ↓□Boards · brandering · cornice
01Orientation-aware board count
02Steel brandering lengths
03Cornice and joint materials
04M-strip or skim finish
01
Ceiling materials
Build the shopping list
Measure each room separately. The tool compares both board orientations and keeps the lower whole-board count before adding your allowance.
02
The method
How the estimate works
Each output shows its assumptions so you can replace defaults with the dimensions, pack sizes and rates available to you.
Size the brandering
Gyproc's estimating guide calculates steel brandering from ceiling area, member length and a 0.38 estimating factor. This is not an installation spacing instruction.
Add joint materials
Tape or M-strip uses board edge length; screws and skim use the published ceiling-area estimating rates.
Check the system
Gyproc's RhinoBoard ceiling guide gives estimating guidance. Confirm the current system details before ordering: RhinoBoard 6.4 mm, RhinoBoard 9 mm, Gyproc Jointed system and the GypCeil M-Strip steel-brandering specification. Sources checked 25 October 2026.
Important boundary
Ceiling sheets are only one part of the system.
Roof structure, brandering support, insulation, moisture exposure, fire performance, lighting and access panels can change the specification.
See all calculators →Real questions
Questions homeowners ask
How many ceiling boards do I need?+
A dependable estimate lays whole boards out room by room, compares both orientations, then adds an allowance. Dividing total area by one board's area can undercount offcuts.
How far apart should ceiling brandering be?+
The referenced Gyproc 6.4 mm M-strip system uses steel branders at 400 mm centres. Other boards and systems can require different spacing.
How do I calculate ceiling brandering?+
The calculator gives a preliminary material takeoff, not a final brandering layout. For a 20 m² room using 3.6 m steel lengths, the area estimate is 20 ÷ (0.38 × 3.6) = 14.62, rounded up to 15 lengths. The 0.38 is an estimating factor; it does not tell an installer to space members 380 mm apart. Gyproc’s 6.4 mm GypCeil M-Strip steel system specifies a maximum of 400 mm centres, but other systems and conditions differ. Check actual runs, joiners, perimeter supports, suspension brackets, cut waste and the current manufacturer detail with the installer before buying.
Can I use the same board thickness and brandering for every ceiling?+
No. A covered-joint M-Strip ceiling and a skimmed or jointed ceiling are different specified systems. Roof support, moisture, fire rating, lighting and ceiling openings may require additional components or a different product. Use this calculator to plan quantities only after selecting an appropriate ceiling system. Ask the supplier or competent installer to confirm the board, spacing, fasteners and suspension details; have any fixtures and loads supported as the system requires, not from plasterboard alone.
How much cornice should I order?+
Add the room perimeter, divide by the stocked cornice length and round up. Include an allowance for mitres, cuts and damaged lengths.
Can the calculator specify the ceiling structure?+
No. It estimates finishing materials; the supporting roof or suspension system must be checked for the selected ceiling and site conditions.