How to Tile a Bathroom Floor: The Complete Guide from Layout Plan to Last Grout Line

Bathroom floors are small. That's supposed to make them easier. It doesn't.

A small floor means every cut is visible. Every sliver along a wall is noticeable. Every misaligned row catches the eye because there's nowhere for it to hide. And bathrooms come loaded with obstacles — toilets, vanity bases, shower trays, door frames, pipe penetrations — each one demanding cuts that larger, simpler rooms never need.

Most bathroom tiling mistakes don't happen during tiling. They happen before it. Wrong tile count. No layout plan. Starting in the wrong spot. Discovering the walls are out of square after three rows are already down. These are planning failures, not tiling failures — and they're the reason so many DIY bathroom floors end up with thin slivers at the edges, mid-project supply runs, and the quiet frustration of a floor that looks almost right but not quite.

This guide covers the entire job from start to finish — but it starts where the mistakes start: with the plan. Get the layout right and the rest of the project flows. Skip the layout and every step after it gets harder.

Step 1: Measure and Map Your Bathroom

Before you think about tiles, you need to know exactly what you're working with. Bathroom measurements are trickier than they look.

Take the Room Dimensions

Measure the full length and width at the widest points. Then measure again at two or three other positions along each axis. If the numbers differ, your walls aren't square — and in bathrooms, they often aren't. A 10mm (⅜″) difference across a 2-metre (6 ft 7 in) span doesn't sound like much, but it means your tile grid will slowly drift out of alignment with the walls as you work across the room. You need to know this before you start, not after Row 6.

Write down the actual measurements, not the rounded ones. If the room is 2,340mm by 1,870mm (7 ft 8 in × 6 ft 2 in), write that. You'll need the real numbers when you plan the layout.

Mark Every Obstacle

Sketch the room on paper (it doesn't need to be pretty) and mark:

• Toilet flange position and footprint. You'll be tiling around this — the toilet comes off before tiling and goes back on after.
• Vanity base (if it's staying). Some people tile under the vanity, some tile up to it. Decide now — it changes the layout.
• Shower tray or wet area boundary. If there's a step-up or a tray edge, measure its position precisely.
• Door frame and threshold. The tiles need to meet the threshold cleanly. Measure how far the frame protrudes from the wall.
• Pipe penetrations. Radiator pipes, waste pipes, any plumbing coming through the floor. Mark each one.

Every obstacle creates cuts. The more accurately you've mapped them, the better your layout plan will be — and the fewer surprises you'll get during installation.

Check for Out-of-Square Walls

Here's the quick test. Measure the diagonal from corner to corner in both directions. If the two diagonals are equal, the room is square. If they differ, it's not.

A room that's out of square means the gap between the tile grid and the wall changes along the length of the wall. On one end, the border tile might be 80mm (3¼″) wide. On the other end, it might be 60mm (2⅜″). If you don't plan for this, the tapered edge can look awkward — especially against a straight vanity or shower tray.

Step 2: Choose Your Tile Size and Pattern

This is where aesthetics and practicality need to shake hands — because what looks great in a showroom photo might not work in your specific bathroom.

Tile Size in Small Spaces

Large-format tiles (300x600mm (12×24″) and above) can make a small bathroom feel bigger because there are fewer grout lines breaking up the surface. But they come with trade-offs in tight spaces: fewer tiles means each cut wastes a bigger proportion of material, and large tiles are harder to fit around obstacles like toilet flanges and pipe penetrations. In a narrow bathroom, a 600mm (24″) tile might leave you with an awkward thin strip along one wall.

Standard tiles (200x200mm to 300x300mm (8×8″ to 12×12″)) are more forgiving in small rooms. More grout lines, but more flexibility in how the grid lands — and cuts waste less material per piece.

Mosaic tiles and small-format hex work beautifully in bathrooms aesthetically, but be aware that the sheer number of edge cuts increases (even if each one wastes less material) and grouting takes significantly longer.

Pattern in Small Spaces

For most bathroom floors, a simple straight lay or staggered bond gives the cleanest result with the least waste. Diagonal, herringbone, and chevron all look stunning — but they increase cuts, waste, and complexity. In a bathroom with multiple obstacles, adding a complex pattern on top of all the obstacle cuts can make installation significantly slower.

If you want a more interesting pattern, factor the extra waste into your material order. A staggered bond might waste 8 to 12 percent; a herringbone in a small bathroom with obstacles could push past 25 percent.

Step 3: Plan Your Layout Before You Buy

This is the step most tiling guides skip — and it's the step that prevents the most expensive mistakes.

Why Layout Planning Matters More in Bathrooms

In a large open room, a minor layout issue might be invisible. In a bathroom, there's nowhere to hide. The border tile width along the most visible wall, the way the grid centres on the doorway, the alignment around the toilet flange — these details are on full display in a space where people stand, sit, and stare at the floor every single day.

Getting the layout right means checking three things before you order tiles:

1. Where's your centre line? Most tilers start from the centre of the room, not from a wall. You find the midpoint of the room in both directions, snap two perpendicular lines, and build the grid outward from there. This ensures the border tiles on opposing walls are roughly equal — so if you can't avoid a cut, at least the cuts are balanced.

2. How wide are the border pieces? Lay out the grid from the centre line and check what's left at each wall. If any border piece is less than half a tile width, shift the entire grid by half a tile. This is the single most important layout check in any tile project. A 30mm sliver along the wall next to the doorway will haunt you every time you walk in.

3. How does the grid interact with obstacles? Check where the tile joints land relative to the toilet flange, the vanity edge, and the shower tray. Sometimes shifting the grid by 20mm avoids a difficult cut around an obstacle — saving time and a tile.

Dry-Laying vs. Planning on Screen

The traditional method: dry-lay the tiles on the floor. Set them out from the centre line, check the borders, adjust. This works — but in a bathroom, it means carrying tiles into a small space, arranging them around obstacles you can't move, and somehow seeing the overall pattern while you're kneeling in a room barely big enough to stand in.

The faster method: a lot of DIYers now plan the layout on screen first. You enter the room dimensions and tile size, place the obstacles, and the planner shows you the full layout — every tile, every border cut, every obstacle interaction. You can shift the starting point and watch the border widths change in real time. You can check whether the grid centres on the doorway. And you get a precise tile count and cut list based on the actual layout, not a percentage guess.

For a simple square bathroom with no obstacles, dry-laying is fine. For a bathroom with a toilet, vanity, shower tray, and door frame — which is most bathrooms — seeing the layout on screen saves significant time and catches problems that are hard to spot from the floor.

If you want to see how your tile lands in the room before you order, try mapping it in a layout planner. Enter your bathroom dimensions and tile size, place the obstacles, and you'll have a material count, a cut list, and a clear picture of the finished floor — all before you've bought a single tile.

Step 4: Order Your Tiles (The Right Amount)

Once your layout is planned, your material order becomes straightforward.

If you have a layout-specific tile count: Order that number, rounded up to the nearest box, plus 2 to 3 extra tiles for breakage and future repairs. Done.

If you're estimating from area: Calculate your bathroom's square metres, then add a waste buffer based on your pattern — 10 percent for a simple straight lay, 12 to 15 percent for a stagger, 15 to 22 percent for herringbone or diagonal. Buy full boxes. Don't open more boxes than you need (unopened boxes are easier to return).

Either way: Order everything from the same production batch. Tile colours can vary subtly between batches. Check the batch number on every box and make sure they match. In a small bathroom, even a slight colour shift is visible.

Step 5: Prepare the Subfloor

Poor subfloor prep is the second most common cause of tiling failures (after poor layout planning). In a bathroom, it's especially critical because of moisture.

Level Check

Lay a long straight edge or spirit level across the floor in multiple directions. The subfloor should be flat to within 3mm (⅛″) over 2 metres (6 ft 7 in). Dips and humps cause tiles to rock, crack under weight, or create lippage (where one tile edge sits higher than its neighbour).

If the floor isn't flat enough, use a self-levelling compound to correct it. Let it cure fully before tiling — rushing this step is how tiles crack six months later.

Priming

Prime the subfloor with an appropriate primer for your substrate (concrete, plywood, or existing tiles). Primer improves adhesive bond and prevents the subfloor from sucking moisture out of the adhesive too quickly.

Waterproofing

This is non-negotiable around wet areas. Apply a tanking membrane or liquid waterproofing to the floor area around the shower, bath, or anywhere water regularly lands. Extend it up the walls by at least 150mm (6″). Let it cure completely before tiling.

Even if your bathroom doesn't have a walk-in shower, a waterproof membrane across the entire floor is good insurance. Bathrooms get splashed. Over years, moisture seeping through grout and into an unprotected subfloor causes rot, mould, and tile failure.

Step 6: Mix Adhesive and Set Your First Tiles

Adhesive Selection

For bathroom floors, use a flexible, cement-based tile adhesive appropriate for your tile type and subfloor. Porcelain and large-format tiles generally need a white flexible adhesive with a longer open time. Natural stone may need a specific rapid-set or white adhesive to prevent discolouration.

Check the adhesive's open time — that's how long you have to lay tiles after spreading it before it skins over. In warm rooms, open time shrinks. Only spread adhesive over an area you can tile within the open time — usually about 1 to 1.5 square metres at a time in a bathroom.

Trowel Selection

Use a notched trowel sized to your tile. General guidelines: 6mm (¼″) notch for wall tiles and mosaics, 10mm (⅜″) notch for floor tiles up to 300mm (12″), 12mm (½″) notch for tiles over 300mm (12″). For large-format tiles, back-butter the tile as well as trowelling the floor (this ensures full coverage and prevents hollow spots).

Laying Sequence

Start from the centre line — not from the wall. Lay full tiles outward toward the walls, following the grid your layout plan established. Use spacers consistently (2mm (1/16″) or 3mm (⅛″) for floor tiles is typical).

Work toward the door. Plan your sequence so you don't tile yourself into a corner. In most bathrooms, this means starting at the far wall and working back toward the doorway.

Check each tile with a spirit level as you go. Press down any high spots. If a tile sits low, pull it up, add adhesive, and reset it. Fixing alignment now takes seconds. Fixing it after the adhesive has set means chipping out tiles.

Step 7: Cut the Boundary and Obstacle Pieces

This is where your layout plan or cut list pays for itself.

Boundary Cuts

If you have a cut list: Each border tile's measurement is already written down. Cut to the listed dimension, minus the spacer width. Dry-fit each piece before spreading adhesive.

If you're measuring on the fly: Place a full tile against the wall, mark the overlap, and cut. Leave the spacer gap. Check the fit before committing.

For straight cuts, a manual tile cutter handles most ceramic and porcelain. For curves or notches, use an angle grinder with a diamond blade or tile nippers.

Toilet Flange

The toilet should already be removed. Tile up to and around the flange. You'll likely need to cut two or three tiles into curved or semicircular shapes to fit snugly around the pipe. Mark the curve on the tile using a template or by scribing around the flange. Cut with an angle grinder or drill-mounted diamond hole saw.

Don't stress about a perfect fit here — the toilet base will cover the cuts. Get the tiles close to the flange, leave a small gap, and make sure the tiles are flat. The toilet mounting bolts go through the flange, not the tiles.

Door Frame

The cleanest finish is to cut the door frame casing so the tile slides underneath. Use an oscillating multi-tool or a handsaw placed flat on a tile (as a height guide) to trim the bottom of the casing. The tile should slide under the frame with a small grout gap.

Pipe Penetrations

For pipes coming through the floor, drill a hole in the tile using a diamond core bit slightly larger than the pipe diameter. If the hole falls near the edge of a tile, cut the tile in a straight line through the centre of the hole — lay one half, then the other, around the pipe. A pipe collar covers the gap.

Step 8: Grout

Let the adhesive cure for at least 24 hours before grouting. Don't rush this — walking on tiles before the adhesive has set can shift them.

Grouting Process

Mix the grout to a smooth, thick paste (like peanut butter). Spread it diagonally across the tiles using a rubber grout float, pushing it firmly into every joint. Work in small sections — roughly 1 to 2 square metres at a time.

After 10 to 15 minutes (check the grout manufacturer's instructions), wipe the surface with a damp sponge. Diagonal strokes, not along the joints — wiping along the joints pulls grout out. Rinse the sponge frequently. Two or three passes should clean the tile faces without disturbing the joints.

Let the grout haze dry, then polish the tiles with a dry cloth.

Sealing

If you've used cement-based grout, apply a grout sealer once the grout is fully cured (usually 24 to 72 hours). This prevents moisture absorption and staining. Reapply annually in wet areas.

Where the floor meets the wall, the shower tray, or the bath: Use flexible silicone sealant, not grout. These junctions move slightly over time, and rigid grout will crack. Match the silicone colour to your grout.

Step 9: Refit and Finish

Once the grout is cured:

• Refit the toilet. Use new wax ring or seal, reset onto the flange bolts, and tighten evenly. Don't overtighten — you'll crack the porcelain or the tile.
• Refit the vanity (if removed). Check that the plumbing connections are accessible.
• Install threshold trim at the doorway if the tile doesn't meet the adjoining floor seamlessly.
• Fit skirting or tile trim along the wall base if required.
• Clean the floor thoroughly. Remove any adhesive residue or grout haze with a tile-specific cleaner.

The Bathroom Floor Tiling Checklist

Here's the full sequence in order. Use this as your at-a-glance reference.

Where Most Projects Go Wrong (and How to Avoid It)

If you've read this far, you've noticed the pattern. The steps that cause the most problems aren't the tiling steps — they're the ones before them.

The most common bathroom tiling failures:

• No layout plan. Starting in a corner and hoping the border cuts work out. They usually don't.
• Wrong tile count. Area plus 10 percent in a bathroom full of obstacles. Under-orders are more common than over-orders. (Here's a better way to figure out how many tiles you need.)
• Ignoring out-of-square walls. Visible taper along the most prominent wall.
• Skipping subfloor prep. Tiles cracking or rocking months later.
• Rushing the adhesive cure. Walking on tiles too soon and shifting the layout.

Every one of these is avoidable with patience and planning. The tiling itself — spreading adhesive, setting tiles, grouting — is learnable. The planning is where the real skill lies. And the good news is that planning doesn't require experience. It just requires measuring carefully, checking the layout, and making sure your material order matches reality.

That's a weekend well spent.