About this calculator
This calculator estimates material quantities for a plasterboard partition wall on a metal CW/UW frame — enter the wall dimensions, the frame profile width and stud spacing, the board size, and the number of sides/layers, and add any openings (doors, windows) separately so they are deducted from the calculated area. It works on one wall at a time, not a room outline, so there is no room-shape option here — shape does not enter this calculator's math.
Formula
wall area = length × height
openings area = Σ (opening width × opening height)
net area = wall area − openings area
Openings are deducted as net area, and each opening is checked so that its sill height plus its own height cannot exceed the wall height (error if it does), and the total openings area cannot exceed the wall area (also an error). Same check order as the wall-tiles, plaster, paint, and wallpaper calculators.
CW studs (vertical, length = wall height):
CW stud count = floor(wall length / stud spacing) + 1
+ opening count × 2 (one extra stud at each opening edge)
CW total length = stud count × wall height
CW stock pieces = ceil(CW total length / profile stock length)
This is a direct formula, not a "fencepost with remainder" count — the last stud lands exactly at the wall's far edge only when the spacing divides the wall length evenly.
UW track (horizontal, floor + ceiling): UW total length = wall length × 2, with the
same ceiling-divide-by-stock-length piece count.
UA reinforced profiles are placed only at door openings (sill height = 0): two profiles per such opening, each cut to that door's own height.
Boards:
boards per side (excl. waste) = ceil(net area / (board width × board height)) × layers per side
waste boards per side = ceil(boards per side (excl. waste) × waste% / 100)
boards per side (incl. waste) = excl. waste + waste boards
boards total = boards per side × number of sides
Waste is applied once per side, not once for the whole total — so the total always equals exactly boards-per-side times sides, with no separate rounding of the same waste twice.
Consumables:
screws = ceil(net area × sides × layers per side × screws/m² / 1,000,000)
joint compound = net area × sides × compound coverage (kg/m²)
The joint compound formula is not multiplied by layers — only the exposed face of each side is finished with compound and tape, regardless of how many board layers sit underneath it.
Joint tape = board-to-board seams (a straight grid, no offset) + the wall's own perimeter, multiplied by the number of sides:
board columns = ceil(wall length / board width)
board rows = ceil(wall height / board height)
vertical seams = (columns − 1) × wall height
horizontal seams = (rows − 1) × wall length
perimeter = 2 × (wall length + wall height)
joint tape = (vertical + horizontal + perimeter) × sides
Acoustic sealing tape = the UW track's own real (not stock-rounded) length.
Insulation (when enabled): area = net area; volume = net area × insulation thickness. Both are zero when disabled.
Build-up depth = profile width + board thickness × layers per side × number of sides. Insulation thickness is not added — it fills the cavity the frame's own width already accounts for, not an extra layer on top of it.
Worked example
Defaults: wall length 4 m, height 2.6 m, no openings, CW/UW profile width 75 mm, stud spacing 600 mm, profile stock length 3000 mm, board 1200×2600 mm, thickness 12.5 mm, 2 sides, 1 layer, insulation off, 12 screws/m², 1.5 kg/m² joint compound, 10% waste.
wall area = 4000 × 2600 = 10,400,000 mm² (no openings, so net area is the same)
CW stud count = floor(4000/600) + 1 = 6 + 1 = 7
CW total length = 7 × 2600 = 18,200 mm
CW stock pieces = ceil(18,200 / 3000) = 7
UW total length = 4000 × 2 = 8,000 mm
UW stock pieces = ceil(8,000 / 3000) = 3
No UA profiles (no door openings)
board area = 1200 × 2600 = 3,120,000 mm²
boards per side (excl. waste) = ceil(10,400,000 / 3,120,000) × 1 = 4
waste boards = ceil(4 × 10 / 100) = 1
boards per side (incl. waste) = 5
boards total = 5 × 2 = 10
screws = ceil(10,400,000 × 2 × 1 × 12 / 1,000,000) = ceil(249.6) = 250
joint compound = 10,400,000 × 2 × 1.5 = 31,200,000 mg ≈ 31.2 kg
board columns = ceil(4000/1200) = 4; board rows = ceil(2600/2600) = 1
vertical seams = 3 × 2600 = 7,800 mm; horizontal seams = 0
perimeter = 2 × (4000+2600) = 13,200 mm
joint tape = (7,800 + 0 + 13,200) × 2 = 42,000 mm = 42 m
acoustic sealing tape = 8,000 mm = 8 m
insulation off -> area = 0, volume = 0
build-up depth = 75 + 12.5(≈13) × 1 × 2 = 101 mm
The calculator returns exactly this for these inputs: 10 boards total (the headline value), 7 CW studs (7 stock pieces), 3 UW stock pieces, 250 screws, ≈31.2 kg of joint compound, 42 m of joint tape, 8 m of acoustic sealing tape, and a 101 mm overall partition thickness.
FAQ
Are openings (doors, windows) deducted from the board, frame, and consumable quantities? Yes, from every area-based quantity (net area → boards, screws, compound, joint tape, insulation) — this differs from the vented-facade calculator, where openings are not deducted from any quantity. CW stud count also increases: one extra stud at each opening edge (two per opening).
Why are CW and UW profiles reported separately from UA? UA is a heavier-gauge, reinforced profile used only to stiffen door (sill height 0) jambs — it is not just another CW stud, so it gets its own line.
What does "stock pieces" mean? CW/UW/UA are sold in fixed-length profiles (3000 or 4000 mm). "Stock pieces" is a simple ceiling-divide of the total length needed by the chosen stock length — not a cut-optimized nesting plan. Real offcuts may let you reuse material across more than one piece, so the actual purchase may end up slightly lower.
Why doesn't joint compound scale with the number of layers, while screws do? Screws fix every board layer separately to the frame or the layer beneath it, so the screw count grows with the number of layers. Joint compound and tape only finish the visible, top surface of each side, regardless of how many layers sit underneath it.
What determines the screw and joint compound consumption? Screw density (per m²) and joint compound coverage (kg/m²) are values you enter, with sensible defaults — not figures from a standard or a specific product's data sheet. They depend on the board fixing pattern and the specific compound product.
Assumptions and limits
No single standard fixing CW/UW stud spacing, board fixing pattern, screw density, or joint
compound coverage for a metal-frame plasterboard partition was found — these depend on each
board/frame manufacturer's own technical approval, not one universal figure, so
meta.standards is deliberately left empty.
CW/UW/UA "stock pieces" is a simple total-length division by the profile's stock length, not a cut-optimized nesting plan — if the wall height exceeds the profile's own stock length, a single stud may genuinely need more than one stock piece (a splice), which this simplified division does not reflect exactly.
Screw density (per m²), joint compound coverage (kg/m²), and the waste percentage are user-supplied estimates with sensible defaults, not standard-derived constants — real consumption depends on the specific product and fixing pattern.
Joint tape is calculated against a straight board grid with no offset (every row starts at the same vertical line) — real installations commonly stagger boards so seams don't align across layers, but that changes seam layout, not total seam length.
Openings are drawn schematically — the calculator does not collect their horizontal position along the wall, so the diagram spaces them evenly in input order, each centred in its own equal slot. For a large wall (many studs or boards) the diagram is simplified to stay legible, which does not affect the quantity math, only the drawing.
Insulation area and volume are exact geometry (net area × thickness) when insulation is enabled — both zero when disabled. Build-up depth is likewise exact geometry (profile width plus board thicknesses), not an estimate.