# Flooring Calculator: How Many Tiles or Boxes for a Room

> A flooring quantity calculation turns a room's area into the number of tiles, carpet tiles or planks to order: floor area plus a wastage allowance for the laying pattern, divided by the area of one piece, rounded up to whole pieces and then to whole boxes.

## What it calculates

For a rectangular room and a chosen tile or plank size, the calculator gives:

- the **floor area** in square feet and square metres;
- the **number of pieces to order**, including wastage for the laying pattern;
- the **number of boxes**, rounded up to whole boxes;
- the **skirting run**, with door openings left out.

It works for vitrified and ceramic tiles, carpet tiles, and vinyl or wooden planks: anything
sold as pieces of a fixed size.

## Inputs

**Room length** and **room width** are the inside dimensions of the room, in feet.

**Tile or plank length** and **width** are the nominal size of one piece, in millimetres:
600 × 600 for a 2 ft vitrified tile, 500 × 500 for most carpet tiles, and the plank size from
the product for vinyl or wood.

**Pieces in a box** is printed on the box label or the product datasheet.

**Laying pattern** sets the wastage: straight lay, diagonal or brick-bond, or herringbone and
chevron.

The **assumptions** panel holds the wastage percentage itself and the total width of door
openings left out of the skirting.

## Method

1. Floor area = length × width, converted to square metres.
2. Area to order = floor area × (1 + wastage).
3. Pieces = area to order ÷ area of one piece, rounded up.
4. Boxes = pieces ÷ pieces in a box, rounded up.
5. Skirting = 2 × (length + width) − door openings.

## Assumptions

| Assumption | Default | Notes |
| --- | --- | --- |
| Wastage, straight lay | 5% | Edge cuts and a few spares |
| Wastage, diagonal or brick-bond | 10% | More cut pieces at the edges |
| Wastage, herringbone or chevron | 15% | Every edge piece cut at an angle |
| Door openings | 3 ft | One standard door; add the widths of all doors |

Wastage figures are planning allowances. Rooms with many corners, columns, ducts or
built-in furniture produce more cut pieces; large-format tiles produce more waste per cut.

## Limitations

- **Rectangular rooms only.** Split other shapes into rectangles and add the results.
- **No allowance for fixed furniture or kitchen units.** If flooring stops at fitted
  furniture, measure the floor that will actually be covered.
- **It does not set out the floor.** Where the first tile starts decides how big the cut
  pieces at the walls are, which affects both looks and waste.
- **It does not include adhesive, grout or underlay.** Those follow the product's own
  coverage figures.
- **Batch and shade.** Order the whole quantity, spares included, from one batch.

## Worked example

A 30 ft × 20 ft room, 600 × 600 mm vitrified tiles in boxes of 4, laid straight:

| Step | Calculation | Result |
| --- | --- | --- |
| Floor area | 30 × 20 | 600 sq ft (55.74 m²) |
| Area to order | 55.74 × 1.05 | 58.53 m² |
| Area of one tile | 0.6 × 0.6 | 0.36 m² |
| Tiles | 58.53 / 0.36, rounded up | 163 |
| Boxes | 163 / 4, rounded up | 41 |
| Skirting | 2 × (30 + 20) − 3 | 97 running ft (29.6 m) |

The order is **163 tiles in 41 boxes**. Laid diagonally instead, at 10% wastage, the same
room needs 171 tiles in 43 boxes.

## How engineers use it

A site engineer or quantity surveyor works from the floor finish drawing rather than a single
rectangle: each finish area is measured separately, wastage is applied by pattern and room
shape, and the setting-out point is fixed before ordering so that cut pieces at doorways and
along the main walls are a sensible size. The take-off also covers the items this calculator
leaves out: adhesive, grout, levelling, underlay, transition strips and skirting.

## When a professional design must replace it

Use the calculator to estimate quantities, compare tile sizes and check a supplier's
quotation. Replace it with a measured take-off from the finish drawings before a large order
is placed, especially where several finishes meet, the floor has a pattern, or the room is
irregular. Where the floor needs levelling or waterproofing first, that work is specified and
measured separately.

## Frequently asked questions

### How much extra flooring should I order for wastage?

It depends on the laying pattern and the room. A straight lay in a regular room wastes the least, a diagonal or brick-bond pattern more, and herringbone or chevron the most, because every piece at the edge is cut at an angle. Small rooms, many corners and large tiles all push wastage up. The calculator starts at 5%, 10% and 15% for the three patterns; change it to suit the room.

### Why should I keep spare tiles after the job?

Tiles from different production batches can differ slightly in shade and size. If a tile cracks later, a spare from the same batch matches; a new one bought years later may not. Keeping a few spares from the original order is cheap insurance.

### How do I calculate tiles for an L-shaped room?

Split the room into rectangles, run the calculator for each one, and add the pieces together before rounding to boxes. Use the higher wastage figure if the shape creates many cut pieces at the corners.

### Is skirting included in the tile count?

No. The calculator gives the skirting run in running feet and metres separately, after leaving out the door openings. Skirting is often a different product, or tiles cut into strips, so it is ordered on its own.

### Does the size on the box match the actual tile size?

Not always exactly. Tiles are sold by a nominal size and the actual size can be slightly smaller to allow for the joint. Use the nominal size for counting pieces, and the area per box printed on the label as a cross-check.

## Sources

- [IS 15622](https://standards.bis.gov.in/website/published-standards/department-wise) — Pressed ceramic tiles: specification

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Source: https://hagerstone.com/calculators/flooring-quantity-calculator