Finishes calculators
21 finishes calculators: tile count, wall tiling, filler, paint, flooring, wallpaper rolls, ceiling framing, plasterboard, skirting, sealant, tile adhesive, grout and drywall partitions.
What this group solves
Finishes are small units in large numbers — tiles by the piece, wallpaper by the roll, filler by the bag, studs by the length — so one wrong factor means hundreds of units of drift. Waste varies enormously: 5-8% for tiling with pattern matching at corners, 10-12% for diagonal layouts, 15% or more for patterned wallpaper, and effectively none for paint once coverage is known. Every tool exposes the waste factor, with a sensible default you can raise.
Ceilings and partitions work the other way: lay out the framing first (main runners, cross tees, hangers), then the boards, then the accessories. Drywall partitions need single or double stud rows plus reinforcement at openings and corners. Stepped ceilings must be measured on the developed area, never the plan projection — that single mistake is the most common loss in a finishes package.
Finishes have a distinctive profile: areas are easy, waste is not. Every material's net quantity follows from area and unit size, and what actually drives the price is the laying pattern and its waste factor. The same 800×800 tile runs 3-5% waste laid square and 10-12% laid diagonally; the same roll of wallpaper differs by a whole roll depending on whether it has a 32 cm repeat. So fix the layout, then the quantity, then openings, corners and trims.
Which one for your case
| How many cans of paint and how many coats | Paint Coverage Calculator |
| Floor or wall tiles — pieces and boxes | Tile Calculator |
| Timber or SPC flooring priced by the square metre | Flooring Quantity Calculator |
| Wallpaper rolls and pattern repeat | Wallpaper Roll Calculator |
| Suspended ceiling grid and board quantities | Ceiling Grid Calculator |
| Metal stud partitions — studs and plasterboard | Steel Stud Partition Calculator |
| Ventilated stone facade modules and quantities | Stone Dry-Hanging Calculator |
| Sealant or grout consumption | Sealant Quantity Calculator |
Where this group goes wrong
- Taking paint area as floor area × 3 across the board. The real factor is 2.8-3.2 and openings must be deducted; two coats cover 8-10 m²/L, not the 12-14 m²/L of a single coat. Using the single-coat figure buys barely half of what is needed.
- Dividing area by unit face area and forgetting waste. 300×600 wall tiles waste 5-8% laid square and up to 12% diagonally; small 100×100 mosaics reach 15% because so much is cut.
- Counting ceiling boards but not the grid. Main runners at 1.0-1.2 m centres come to about 0.9 m/m², cross tees at 400 mm to about 2.5 m/m², hangers 1-2 per m², plus perimeter trim by the metre — these are the lines most often missing from a ceiling price.
- Pricing a stone facade by wall area without regard to module size. A 1200×800 module and a 1000×1000 module waste very differently, and mullion count is the module count plus one — not the wall length split evenly.