Sizes a plaster of Paris ceiling from the area you are covering and the thickness you build.
Painting, tiling and finishes. 5 questions answered below, each with the arithmetic behind it and the limits of what the tool decides. Open the POP Ceiling Calculator tool.
A POP ceiling is priced by three things that are easy to confuse: the board area that covers the room, the framing that holds it, and the compound that joints and finishes it. A room count gets none of them right, and an area alone misses the framing entirely, which is where a ceiling budget usually goes wrong. The calculator takes each room's length and width, builds the area and the perimeter from them, and carries both into the quantities. Ceilings are not floors. The area decides board and compound, the perimeter decides screed, channel and trim, and the height of the room decides nothing at all except the scaffold you will need. Because a long narrow room and a square room can share an area and differ by several metres of perimeter, the tool keeps the two measurements apart and prices each against its own rule.
A living room six metres by four and a half gives twenty seven square metres and a perimeter of twenty one metres. A second room three metres by nine gives the same twenty seven square metres but a perimeter of twenty four metres. Board quantities are identical, and the framing differs by three metres of screed and trim, which is the difference the room count would have hidden. At a board size of one and a half by one and a bit metres covering close to two square metres per board, the first room needs fourteen boards before waste. Compound follows the joints those boards create, and trim follows the twenty one metres, not the area.
Multiply each room's length by its width for the area, then add the perimeter for the framing, and it is the second figure that a quick estimate usually forgets. The calculator takes the dimensions room by room, converts the total area into boards at the size you specify, and converts the total perimeter into screed, channel and trim. Compound then follows the joints the chosen board size creates, so a smaller board raises both the board count and the compound.
It uses the dimensions of the design you are building, so a simple flat ceiling is priced accurately and a design with steps, coves or curves needs those features measured as extra runs. Measurement is yours to take, and the arithmetic on top of it is the calculator's. That division matters on a decorated ceiling, because the design detail is geometry rather than something a rate per square metre can carry.
They are not included. The estimate covers board, framing, compound, tape and trim, which is what you need to order before the work starts. Labour follows the design and the access, and scaffold depends on the ceiling height and what is underneath. Both are priced separately, and putting them into a material estimate produces a number that is accurate for neither.
Not reliably. Two rooms of the same count can differ by several square metres and by more in perimeter, which is what drives the framing. Entering each room's length and width takes a minute and gives an area and a perimeter the estimate can actually use. A room count is a budgeting shorthand, and the calculator is designed to replace it with the measurement the order depends on.
Screed, channel and trim follow the perimeter of each room, so a long narrow room needs more of all three than a square room of the same area. The calculator takes the perimeter from the dimensions you enter and prices the framing against it. This is why an estimate built from area alone under orders on circulation spaces, corridors and long living rooms, and why the perimeter appears as its own line.