Materials take-off
Enter an area and read off the sheets, the weight, the framing, the joint length and the fixing rules for the job. Every figure carries a line saying where it came from — published by Cemtone, or worked out here from a published figure.
The take-off
JavaScript is switched off. The figures below are a worked example for 500 sq ft (46.45 m²) of interior wall at 6 mm — the controls arrived in. They will not change when you change a field. Everything the calculator uses is published further down this page, so the take-off can be done by hand: divide the area by 2.9768 and round up.
Take-off for interior wall
500 sq ft — 46.45 m² at 6 mm
16 sheets · 384 kg · 97–136 m of framing · 58 m of joint
Fixing rules that apply here. Gap between boards 2–3 mm. Screws 200–300 mm apart along an edge, 300–400 mm apart in the field. 75 mm clear of a corner. 30 mm clear of an edge. Drill pilot holes — do not punch them.
The board starts 100 mm above floor level.
Published by Cemtone
Every figure in this block is Cemtone's own. The calculator does arithmetic on these and nothing else.
Every sheet is 1220 × 2440 mm, which is 2.9768 m². Custom sizes can be manufactured to suit a project — ask, if a sheet that fits the module beats a sheet that needs cutting.
| Thickness | Weight per sheet | Weight per m² |
|---|---|---|
| 6 mm | 24 kg | 8.1 kg |
| 8 mm | 32 kg | 10.7 kg |
| 9 mm | 36 kg | 12.1 kg |
| 10 mm | 40 kg | 13.4 kg |
| 12 mm | 48 kg | 16.1 kg |
| 15 mm | 60 kg | 20.2 kg |
| 18 mm | 72 kg | 24.2 kg |
| Application | Thickness | Framing centres |
|---|---|---|
| Interior wall | 6, 8, 9 or 10 mm | Verticals 400 ±10 to 600 ±10 mm · horizontals 2440 mm |
| Internal wall underlay | 8, 9, 10 or 12 mm | Verticals 400 ±10 to 600 ±10 mm · horizontals 2440 mm |
| Ceiling | 6, 8 or 9 mm | 400 ±10 to 600 ±10 mm |
| External wall / facade | 10, 12, 15 or 18 mm | Verticals 400 ±10 to 600 ±10 mm · horizontals 2440 mm |
| External / internal floor | 12, 15 or 18 mm | 400 ±10 × 400 ±10 mm grid |
| Floor underlay (interior) | 9, 10 or 12 mm | 400 ±10 × 400 ±10 mm grid |
| Sub roof | 9, 10, 12 or 15 mm | As the roof tile manual directs — no centres published |
| Wet area, under ceramic tile | 8, 9, 10 or 12 mm | Verticals 400 ±10 to 600 ±10 mm · horizontals 2440 mm |
Sub roof is the one application with no framing figure. Cemtone publishes framing and spacing for a sub roof as whatever the roof tile manual directs, so the calculator returns no linear metres for it rather than borrowing a number from another application.
Published by Cemtone
These five hold for every application, at every thickness.
| Rule | Figure |
|---|---|
| Gap between boards | 2–3 mm |
| Screws along a board edge | 200–300 mm apart |
| Screws in the field of the board | 300–400 mm apart |
| Clear of a corner | 75 mm |
| Clear of an edge | 30 mm |
Drill pilot holes — do not punch them.
| Application | In addition |
|---|---|
| Interior wall | Board starts 100 mm above floor level |
| Internal wall underlay | Board starts 100 mm above floor level |
| External wall / facade | Board starts 100 mm above floor level |
| Wet area, under ceramic tile | Board starts 100 mm above floor level · bonding coat, then 1–4 hours to set before the adhesive · tiles not larger than 600 × 600 mm |
| Ceiling | Nothing beyond the five rules above |
| External / internal floor | Nothing beyond the five rules above |
| Floor underlay (interior) | Nothing beyond the five rules above |
| Sub roof | Nothing beyond the five rules above |
No screw is specified. Cemtone publishes how far apart the screws go and how far they stay off an edge and a corner. It does not publish a type, a gauge, a length or a corrosion grade, so this page gives none. Take the screw itself from the engineer's specification.
Provenance
Two kinds of number appear in the panel. Cemtone's own, and arithmetic done here on Cemtone's own. The second kind is marked Derived wherever it appears.
| Figure | Where it comes from |
|---|---|
| Sheet size and area | Published. 1220 × 2440 mm, which is 2.9768 m² |
| Weight per sheet | Published. 24, 32, 36, 40, 48, 60 and 72 kg per sheet at 6, 8, 9, 10, 12, 15 and 18 mm, and 8.1 to 24.2 kg per m² |
| Valid thicknesses | Published per application |
| Framing centres | Published per application |
| Gaps, screw spacing, edge and corner clearances | Published, and the same for every application |
| Sheets required | Arithmetic: area ÷ 2.9768, rounded up to a whole sheet |
| Total weight | Arithmetic: sheets × the published weight per sheet |
| Framing, linear metres | Derived from the published centres — not a Cemtone figure |
| Joint length and mesh tape | Derived from the published sheet size — not a Cemtone figure |
| Fixing positions | Derived from the published spacing — not a Cemtone figure |
| Price | Not published. Cemtone publishes no prices, so this page shows none. Ask Cemtone |
| Waste allowance | Not published. The field starts at nought and this page recommends no figure |
| Putty or adhesive quantity | Not published. There is no coverage figure, so no quantity is given |
| Screw type, gauge, length or grade | Not published. Spacing only |
Framing. From the published centres for the application. On a wall that is one vertical per 400 to 600 mm of length running the full height, plus one horizontal per 2440 mm of height running the full length. On a floor it is the 400 × 400 mm grid, counted both ways. On a ceiling Cemtone publishes a single frame spacing, so one direction is counted and no cross-member is assumed — the joists are taken as running across the length you entered. A sub roof gets no figure at all.
Give a length and a height and the frame is set out on that face, including the member at each end of a run. Give an area alone and the figure is a rate per square metre, which cannot know where the ends are and so leaves those members out. The panel says which of the two it used. The pair of numbers is the widest published centres and the tightest.
Joint length and mesh tape. From the sheet module. Give a length and a height and the boards are laid out on that face — 1220 mm across the length, 2440 mm up it — and the joints between them are measured. Give an area alone and the figure is 1.2295 m of joint per square metre, which is half the perimeter of one sheet over the area of one sheet. Mesh tape runs the same length as the joint.
Fixing positions. From the published spacing and nothing else. On each sheet: a line of fixings 30 mm in from every edge, spaced at 200 to 300 mm, and a grid inside that line spaced at 300 to 400 mm. Corners are left clear by the published 75 mm. The low figure uses the widest published spacing throughout, the high figure the tightest. It is not a Cemtone figure. On site every fixing goes into framing, so the frame set-out, not this arithmetic, decides how many are really used — which is why the spacing rules are printed above in full and the count is offered second.
Waste. Whatever you type is added to the area before the sheets are counted, and to nothing else. Framing and joint length stay on the area you entered, because an offcut of board is not an offcut of stud.
These are general manufacturer recommendations. All site installation work shall be carried out in accordance to engineer specifications.
The board itself — what it is made of, and which thickness belongs on which job — is on the board page. The fixing detail frame by frame, application by application, is on the installation page. A quantity, a custom sheet size or a price is a question for Cemtone.