# How many floor tiles do I need for a garage?

_Published by CAVE4MAN (https://cave4man.com) — storage, workshop and man-cave kit for UK home garages. The shop has not opened yet; nothing here can be ordered today._

_Updated 2026-09-19 · 7 min read_

**The short answer**

Count garage floor tiles by rows, not by area. Divide the floor width by the tile width and round up, divide the floor length by the tile length and round up, then multiply. That builds the cutting allowance in. Add a few spares for damage. The tile size comes from the listing of the tile you buy, and sizes differ.

**In this guide**

1. [Area divided by tile size gets the answer wrong](https://cave4man.com/guides/how-many-floor-tiles-for-a-garage#area-divided-by-tile-size-gets-the-answer-wrong)
2. [Measure the floor, not the garage](https://cave4man.com/guides/how-many-floor-tiles-for-a-garage#measure-the-floor-not-the-garage)
3. [A worked example, and where the numbers in it come from](https://cave4man.com/guides/how-many-floor-tiles-for-a-garage#a-worked-example-and-where-the-numbers-in-it-come-from)
4. [What the tile itself changes](https://cave4man.com/guides/how-many-floor-tiles-for-a-garage#what-the-tile-itself-changes)
5. [Where the count goes wrong](https://cave4man.com/guides/how-many-floor-tiles-for-a-garage#where-the-count-goes-wrong)

## Area divided by tile size gets the answer wrong

Floor area divided by the area of one tile is the sum most guides give, and it undercounts, sometimes by a lot. It assumes every offcut goes back into the floor, and with interlocking tiles that is not what happens. A tile cut to fill the last half-row along one wall leaves an offcut with an interlock on the wrong edges, and it usually cannot be turned and used to fill the last half-row along the other wall. The area sum treats it as if it could.

Counting by rows fixes that without a guess. Work out how many tiles fit across the width, rounding up, and how many fit along the length, rounding up, and multiply. Rounding up on both axes is the cutting allowance, built in and exact for your floor, rather than a percentage somebody added on top of the area sum because they knew it was low. The two methods are compared below on the same floor, and the difference is real tiles.


## Measure the floor, not the garage

Tiles go on the floor, so measure at floor level, which is not the same as measuring the room. A garage that is a clean rectangle at head height can be an awkward shape at the slab: a pier that stands proud of the wall, a step up to the house door, a boiler cupboard, a drain, and the door threshold, which on many garages is a raised lip rather than a flat edge. Each of those is an edge you cut around.

Take the longest length and the widest width at floor level and treat the floor as that rectangle for the count. Anything that intrudes into it is a cut, and cuts are already covered by rounding up. Then note the threshold separately, because whether the tiles run to the door or stop short of it, and whether they need a ramped edge there, changes the count along one row and is the question people forget until the last box.

1. **Clear the floor** — Move the car out and anything freestanding off the slab. You need a tape on the actual concrete, corner to corner, not a guess around a shelving unit.
2. **Measure the width at floor level** — At the widest point, wall to wall along the slab. If a pier narrows the floor partway down, ignore it for the count and treat it as a cut.
3. **Measure the length at floor level** — From the door threshold to the back wall. Decide now whether the tiles run over the threshold, stop at it, or finish with a ramped edge in front of it, because that sets where this measurement ends.
4. **Read the tile size off the listing** — Interlocking tiles are sold in several sizes and the count depends entirely on which. Read the tile’s stated length and width, and check whether the stated size is the tile edge to edge or the coverage once interlocked, which can differ.
5. **Do the row count** — Floor width divided by tile width, rounded up. Floor length divided by tile length, rounded up. Multiply the two whole numbers. That is the tile count including cuts.
6. **Add spares** — A handful of extra tiles, so that a section damaged by a dropped jack or a hot exhaust in two years’ time can be lifted and swapped from stock rather than matched to a batch that may no longer exist.


## A worked example, and where the numbers in it come from

Say the floor measures 2.6 metres wide and 5.4 metres long at slab level. For the example, take a tile that measures 400mm by 400mm. That is a size these tiles are commonly sold at; it is an illustration, not a specification, and it is not read from any particular product, so do the sum again with the size stated on the listing of the tile you actually buy.

By area: 2.6 times 5.4 is 14.04 square metres, and a 400mm tile covers 0.16 square metres, so the sum gives 87.75, rounded up to 88 tiles. By rows: 2,600 divided by 400 is 6.5, rounded up to 7 tiles across; 5,400 divided by 400 is 13.5, rounded up to 14 tiles along; 7 times 14 is 98 tiles. The row count is ten tiles more on this floor, and those ten tiles are the half-row of cuts along each of two walls that the area method assumed could be made from offcuts.

Change the tile size and the gap between the two methods changes with it. The worse the floor dimensions divide by the tile, the bigger the difference, which is why the row count is the one to trust: it is exact for your floor, and the area method is exact for nobody’s. A floor that happens to divide cleanly on both axes gives the same answer both ways, and that is the only floor on which the area method is right.

| Method | Sum on the example floor | Result | What it misses |
| --- | --- | --- | --- |
| Area | 14.04 m² divided by 0.16 m² | 88 tiles | Half-row cuts that cannot be reused |
| Rows | 7 across times 14 along | 98 tiles | Nothing, for a rectangular floor |
| Rows plus spares | 98 plus a few for damage | 98 and upwards | Nothing |


## What the tile itself changes

Two tiles that look the same size can count differently. Some listings state the tile edge to edge; others state the coverage once the interlocks are engaged, which is slightly less because the tabs of one tile sit inside the next. On a long run that difference adds up to a tile or more. Read which the listing means, and if it is not clear, measure a single tile once it arrives before ordering the rest.

Edge ramps and corner pieces are usually counted separately from the tiles, and they matter at the threshold and anywhere the tiled floor meets a bare one. Whether you need them depends on the decision you made when measuring the length: tiles that run all the way to the door and stop dead present an edge to the car tyre and to a foot in the dark, and a ramp is the fix.

Our interlocking tiles are polypropylene, click together without adhesive, and are sold per tile, so the count above is the order. Measure the floor first, because it is the floor that sets the number and not the garage type: a single garage is often quoted at around eighteen square metres, but yours is whatever the tape says, and the tape is the only figure that goes on the order.


## Where the count goes wrong

The commonest error is measuring the garage from a plan or an estate agent’s listing rather than the slab. Those figures describe the building, not the floor you can tile, and they are often rounded. The second is forgetting the threshold decision, which changes the length by a tile. The third is taking the tile size from a photograph of somebody else’s floor and assuming yours will match.

Freestanding shelving is the other thing to think about before ordering. A five-tier unit stands on the tiles, so if the tiles go in first the count includes the floor under it. If the unit is already there and staying, you can tile up to it and save a few tiles, but you cannot then move it without a gap in the floor. Tiling the whole slab and standing the unit on top is the version that lets you change your mind.

## Common questions

**How do I work out how many garage floor tiles I need?**

Measure the floor at slab level, then read the tile size off the listing. Divide the floor width by the tile width and round up, divide the floor length by the tile length and round up, and multiply the two. That count includes the cuts along two walls. Add a few spare tiles so a damaged section can be swapped later.

**Should I add extra tiles for cutting?**

If you count by rows and round up on both axes, the cuts are already in the count and you do not need a separate cutting allowance. If you divide area by tile area instead, you do, because that method assumes offcuts can be reused across both walls and with interlocking tiles they usually cannot.

**What size are interlocking garage floor tiles?**

They are sold in several sizes, and the same nominal size can be stated edge to edge or as the covered area once interlocked, which is slightly less. There is no single standard. Take the size from the listing of the tile you are buying, check which measurement it means, and do your count from that.

**How many square metres is a single garage floor?**

A single garage is often quoted at around eighteen square metres, but there is no standard size and yours may be well off that. Measure the slab at floor level from the door threshold to the back wall and wall to wall at the widest point, and count from those figures rather than from a typical number.

## Kit that does the job

- **Interlocking garage floor tiles** — £59.99, not yet on sale (https://cave4man.com/product/interlocking-floor-tiles)

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Guide page: https://cave4man.com/guides/how-many-floor-tiles-for-a-garage