Large tiles in the bathroom: advantages and installation constraints

A clean, minimalist finish that requires particularly precise support and installation.

Large tiles are increasingly common in bathrooms. They reduce the number of grout lines, highlight the effects of stone or concrete, and create visually continuous surfaces.

However, a large tile is not installed like a traditional format. The larger its surface area, the less it can conform to the irregularities of the wall or floor. Therefore, preparing the substrate, handling the tiles, choosing the right adhesive, and planning the cuts become essential.

The result can be spectacular, even in a small bathroom, but only if the format is adapted to the room and its constraints.

Installing Large Tiles in a Shower

What is a large square?

The difficulty begins well before the full-height panels

In the industry, a tile with at least one side measuring 15 inches or more is generally considered large format. This category therefore includes several dimensions:

• 12 × 24 inches;

• 24 × 24 inches;

• 24 × 48 inches;

• 30 × 60 inches;

• very elongated tiles;

• porcelain panels covering almost an entire wall.

A 12 × 24 inch tile is common in bathrooms today, but it already requires a flatter support than a small ceramic tile.

Very thin and very large panels form an even more specialized category. Their transport, cutting and installation require specific tools and methods.

The choice should therefore not be based solely on an inspirational photo. The weight, thickness, dimensions of the room, and the possibility of handling the tile to its final placement must all be taken into account.

Why choose large tiles?

Their main advantage is visual continuity

Large formats divide surfaces less. The eye is drawn more to the material and less to the grid created by the joints.

They are particularly well-suited for imitations:

• marble;

• travertine;

• concrete;

• of limestone;

• of terrazzo;

• wood;

• of metal.

Veined patterns gain depth when spread over a large area. With careful planning, the veins can even extend from one tile to the next.

Large tiles also offer other advantages:

• fewer grout lines;

• simplified daily maintenance;

• a contemporary appearance;

• improved highlighting of textures;

• a possible continuity between the floor and the walls;

• an impression of visual calm.

They don't automatically make a room look larger. However, well-proportioned layouts and discreet joints can reduce visual fragmentation and create a more uniform sense of space.

Are they suitable for small bathrooms?

A small space doesn't require small tiles

The idea that large formats are only suitable for large rooms is misleading. They can work very well in a compact bathroom.

A 24 x 48-inch tile, for example, can cover a large portion of a shower wall with very few grout lines. The result often looks more understated than a series of smaller tiles.

However, the following must be monitored:

• the number of cuts;

• the width of the remaining strips;

• the position of vanity;

• the angles;

• the niches;

• plumbing openings;

• the ceiling height.

In a very small room, a huge tile panel can lead to a lot of waste if each tile has to be cut around the fixtures. A slightly smaller format can offer better balance and reduce waste.

The right size is the one that allows for harmonious cuts, not necessarily the largest one offered in store.

Does fewer seals mean less maintenance?

The surface is easier to wipe clean, without becoming maintenance-free.

Large tiles reduce the overall length of grout lines. Therefore, there are fewer porous or textured lines to scrub.

This advantage is particularly noticeable in:

• shower walls;

• the outline of a bathtub;

• the floor;

• the walls behind the vanity.

The large surface area of the tile must be cleaned like any other surface. On a dark or glossy finish, water droplets and mineral deposits may become more visible.

The reduced number of joints does not replace proper sealing. The ceramic and grout form the visible surface, while the membrane behind it actually protects the assembly from water.

Does the surface need to be perfectly flat?

Large tiles reveal even the slightest irregularity

The flatness of the substrate is one of the main constraints during installation. A small tile can accommodate slight variations. A large, rigid tile rests on a much larger surface and will tip over any bumps or dips.

Two concepts must be distinguished:

• a level support , perfectly horizontal;

• a flat surface , without bumps or significant depressions.

A shower floor must be sloped towards the drain: it is therefore not level. However, each of its surfaces must be even.

For large format tiles, North American standards impose stricter flatness tolerances. MAPEI Canada specifically mentions a tolerance of 1/8 inch over 10 feet for tiles where at least one side measures 15 inches or more.

In practice, preparation may require:

• grinding from a high point;

• a leveling compound;

• a levelling compound;

• a self-levelling underlay;

• the correction of a wall;

• the replacement of deformed panels.

Cement adhesive should not be used to improvise and correct major irregularities during installation.

Why is the plumb of the walls important?

A sloping wall complicates angles and connections.

In a shower, large tiles meet several elements: ceiling, base, niche, faucets and glass wall.

If a wall isn't straight or an angle isn't square, the cuts will gradually become wider or narrower. With a large format, these variations are immediately visible.

A well-prepared wall makes it easier to:

• the alignment of the joints;

• encounters in the corners;

• the finishing around a niche;

• the installation of the profiles;

• the installation of the glass;

• the cuts in the ceiling.

Therefore, it is often preferable to correct the structure or panels before installing the membrane and ceramic.

Are the large tiles perfectly flat?

The shape and baking process may produce a slight curvature.

Even a new tile can have a slight deformation. Rectangular formats are sometimes slightly arched in the center.

This characteristic influences the laying pattern. A half offset can place the highest point of one tile next to the lowest point of the next, creating a visible difference in level.

Before confirming the layout, you should consult the manufacturer's recommendations and examine several tiles from the batch.

A perfectly aligned installation or a less pronounced offset may be better suited to certain products. The choice should be made based on the actual tile, and not solely on a catalogue image.

What are leveling systems used for?

The shims limit the gaps, but do not correct the support

Leveling clips and wedges hold two adjacent tiles in a consistent position while the mortar sets. They help reduce height differences between edges.

However, they cannot:

• straighten a curved wall;

• remove a bump in the floor;

• correcting a distorted tile;

• replace a sufficient quantity of mortar;

• create a functional slope.

Excessive pressure can even lift a tile and create a void beneath its surface.

The leveling system is therefore a laying tool, and not a solution to poor preparation.

Which cement-adhesive should I use?

The weight and surface area require a suitable product

A large tile requires a mortar capable of supporting it without excessive sagging. On a wall, the product must also limit slippage before setting.

The tile adhesive should be chosen according to:

• the format;

• the weight;

• the support;

• the membrane;

• the type of tile;

• the dry or humid location;

• Manufacturers' recommendations.

Special mortars are formulated for large-format heavy tiles. They offer a consistency that supports the tile while ensuring proper adhesion.

The choice of products must be consistent with the waterproofing system used. Not all tile adhesives are suitable for all membranes or tiles.

Why is mortar coverage essential?

A large tile should not rest on just a few points of support.

The mortar must support the tile surface uniformly. Large voids can weaken the covering, especially around edges, corners, and openings.

In wet areas, near-complete coverage is required. CUSTOM Building Products ' technical specifications specifically call for at least 95% coverage in wet areas, with properly supported edges.

To obtain this coverage, the installer can:

• use a suitable trowel;

• apply the furrows in the same direction;

• coat the back of the tile;

• move the tile perpendicular to the grooves;

• periodically lift a piece to check the transfer.

Double gluing is not simply about adding a random thickness. It aims to fill the contours of the back and promote continuous contact with the substrate mortar.

Why do haircuts require more preparation?

A single mistake can compromise an expensive tile

Cutting a large tile requires sufficient workspace and appropriate equipment. The tile must be supported along its entire length to prevent it from bending or breaking.

Openings intended for plumbing are particularly delicate:

• shower valve;

• water outlets;

• wall-mounted taps;

• drain;

• sockets;

• lighting;

• niche.

An opening too close to an edge weakens the tile. An inaccurate measurement can render the entire room unusable.

You should also plan for extra tiles. Waste doesn't depend solely on the surface area: the layout and cuts may require using a completely new piece to replace a strip or work around an opening.

Is handling more difficult?

Weight and bulk change the organization of the construction site

A large tile can be heavy, fragile and difficult to turn in a corridor or small bathroom.

Before ordering, you must check:

• the width of the doors;

• the corners of the corridor;

• access via the stairs;

• the dimensions of the elevator;

• the space available for the cuts;

• the storage area;

• the number of people needed.

Very large formats are often handled with suction cups, rigid frames and specific cutting tables.

In a condo, delivery and handling sometimes need to be coordinated with the building's rules. A sign that appears in the bathroom on the floor plan may not fit in the elevator or stairwell.

Can large tiles be laid on the floor?

The coating must be suitable for a wet surface

Large tiles can be installed on the main bathroom floor if the support is sufficiently flat and rigid.

However, their finish must provide adequate grip. A highly polished surface can become slippery when wet.

The choice must take into account:

• texture;

• of the intended use;

• manufacturer's recommendations;

• of the frequency of splashing;

• the presence of underfloor heating;

• of the interview.

The joints provide some additional grip. A larger format has fewer joints; therefore, the surface texture becomes particularly important.

Can large tiles be used in the shower?

The walls and the floor do not present the same constraints

Large formats are very well suited to shower walls. They reduce the number of joints and highlight stone or marble finishes.

The floor is more complex. With a central drain, the water must converge from several directions. A large tile cannot follow these slopes without being cut.

Several solutions are possible:

• use large tiles on the walls and mosaic on the floor;

• choose an intermediate format for the floor;

• cut the tiles according to the different plans;

• install a linear drain allowing for a single slope.

A linear drain can make it easier to use large tiles in the shower, as the floor can slope down to the drain on a single plane.

However, feasibility depends on the structure, the available height, and the position of the drain.

How to integrate a shower niche?

The dimensions must be coordinated with the joints

A niche creates several cuts in a wall. With large tiles, it must be positioned according to the tile layout to avoid very small strips around the opening.

You should plan for:

• the finished width of the niche;

• its height;

• the thickness of the tablets;

• the position of the joints;

• edge treatment;

• the pattern of the tile;

• the possible continuity of the veins.

A prefabricated niche should not be installed without considering the tile size. A slight vertical adjustment can allow its top and bottom to be aligned with the main grout lines.

How to choose the width of the joints?

A discreet joint is not necessarily an almost invisible joint

Large tiles are often associated with narrow grout lines. However, their width depends on:

• of the regularity of the tile;

• of its rectification;

• of its deformation;

• of the laying pattern;

• manufacturer's recommendations;

• support;

• of the location.

Too narrow a width can make dimensional variations more visible and complicate alignment.

The choice of grout color also influences the result. A tone close to the ceramic reduces the visual grid, while a contrast highlights each format.

Plane changes and movement joints must receive appropriate treatment. They should not be filled indiscriminately like regular joints.

Are large tiles compatible with underfloor heating?

A continuous surface efficiently diffuses heat

Porcelain conducts heat well and is generally suitable for underfloor heating systems.

However, the success of the assembly depends on several factors:

• stability of the support;

• membrane used;

• mortar compatibility;

• covering under the tiles;

• movement joints;

• gradual commissioning.

A gap under a large tile creates an unsupported area and can disrupt the even distribution of heat. Therefore, proper installation remains essential.

The temperature and commissioning time must comply with the instructions of the cable, mortar and grout manufacturers.

Do larger formats cost more to install?

The price of the tile represents only part of the budget

The cost depends on the product chosen, but also on the preparation and the application time.

The budget may increase due to:

• leveling of walls or floor;

• specialized cement-adhesive;

• cutting tools;

• suction cups and handling frames;

• work requiring two people;

• cuts around the plumbing;

• losses;

• the difficulty of access;

• of the treatment of patterns or veins.

An affordable tile can therefore lead to a demanding installation. Conversely, a format well-suited to the room can reduce the number of tiles to install and offer an excellent result without adding unnecessary detail.

The evaluation should focus on the entire project rather than the price per square foot of the ceramic tiles.

The most common mistakes

The apparent simplicity of the result hides a demanding process.

The main mistakes to avoid are:

1. Choosing the largest format without studying the room.

   
   

   Losses and cuts can become disproportionate.

2. Place on an uneven surface.

   
   

   The edges do not align and gaps form under the tiles.

3. Use tile adhesive to correct the substrate.

   
   

   The thickness becomes uneven and the tile can sag.

4. Believing that clips correct flaws.

   
   

   They do not replace prior leveling.

5. Ignoring the back cover.

   
   

   The corners and edges remain poorly supported.

6. Improvise the layout.

   
   

   Small bands appear near the ceiling, corners, or niche.

7. Underestimating the handling.

   
   

   The tile either doesn't fit through the door or breaks during its movement.

8. Choosing a finish that is too slippery on the floor.

   
   

   Appearance takes precedence over safety.

9. Use large tiles around a central drain without a cut plan.

   
   

   The slopes become irregular.

10. Forget about spare parts.

    
    

    A future replacement becomes difficult if the model is discontinued.

Plan the installation before ordering

Precise layout planning helps confirm the correct format

Before making a purchase, it is helpful to prepare a plan outlining:

• the finished dimensions of the walls;

• the position of the devices;

• plumbing openings;

• the niches;

• the angles;

• the ceiling height;

• the direction of the pose;

• the joint lines;

• the main sections;

• the projected losses.

The measurements must be taken after determining the thickness of the panels, the membrane and other finishing layers.

For a veined tile, the boxes can also be opened and the pieces arranged dry in order to organize the pattern before installation.

BonBain's integration of large tiles

Match the format to the support and the actual configuration

Large tiles can create an elegant, calming, and easy-to-maintain bathroom. However, their success depends much more on preparation and precision than their sleek appearance might suggest.

BonBain can check the condition of the supports, prepare the layout and coordinate the ceramics with the shower, plumbing, niches and furniture.

To have your project evaluated, fill out the BonBain free estimate request .