What Are Movement Joints and Why Are They Important?

Movement joints are specially designed gaps within a tiled installation that allow the floor or wall to expand, contract and move without placing excessive stress on the tiles.

Although they are often overlooked because of their appearance, movement joints play a vital role in the long-term performance of tiled surfaces. Without them, natural movement within a building can cause tiles to crack, lift or become detached.

Every building moves. The purpose of movement joints is to ensure the tiled surface can accommodate that movement safely.

Why Do Buildings Move?

Many people assume a building is completely rigid, but this is not the case.

Movement occurs for many reasons, including:

• Changes in temperature.
• Underfloor heating.
• Drying shrinkage of concrete and screeds.
• Moisture expansion and contraction.
• Structural settlement.
• Normal building movement.

Although these movements are often very small, they can create significant stresses over a large tiled area.

What Is a Movement Joint?

A movement joint is a deliberate gap within a tiled installation that is filled with a flexible material rather than rigid grout.

Instead of resisting movement, the joint allows controlled movement to occur without transferring excessive stress into the tiles.

Movement joints are an essential part of many professional tile installations.

Where Should Movement Joints Be Installed?

The location of movement joints depends on the size of the installation, the substrate and the environment.

Common locations include:

• Around the perimeter of floors.
• Where floors meet walls.
• Internal corners.
• Changes in floor direction.
• Doorways between rooms.
• Large uninterrupted tiled areas.
• Around structural columns.
• Over structural movement joints in the building.
• Between different substrates.

The exact requirements should always follow recognised installation guidance and the tile or adhesive manufacturer's recommendations.

Movement Joints and Underfloor Heating

Underfloor heating causes repeated cycles of expansion and contraction as the floor warms and cools.

Movement joints help accommodate these thermal movements and reduce the stresses placed on the tiled surface.

For this reason, they are particularly important in heated floors.

What Are Movement Joints Made From?

Movement joints are usually formed using flexible materials designed to accommodate movement. These may include:

• Flexible sealants.
• Pre-formed movement joint profiles.
• Expansion joint systems.

The appropriate product depends on the location and the expected movement.

What Happens If Movement Joints Are Omitted?

Without suitable movement joints, stresses can gradually build within the tiled installation.

Possible consequences include:

• Cracked tiles.
• Cracked grout.
• Tiles lifting from the floor (tenting).
• Debonding.
• Hollow-sounding tiles.
• Premature installation failure.

In many cases, the damage develops gradually over months or years.

Why Are Movement Joints Sometimes Omitted?

There are several reasons why movement joints may not be included.

Sometimes homeowners prefer an uninterrupted tiled surface because they believe flexible joints will be more noticeable than grout.

In other cases:

• The installer may underestimate the amount of movement likely to occur.
• Existing movement joints in the substrate may be overlooked.
• The installation may pre-date current best practice.
• The importance of movement accommodation may not be fully understood.

Whatever the reason, omitting movement joints can increase the risk of future problems.

Are Perimeter Joints Hidden?

Yes, in many installations.

Perimeter movement joints are often concealed beneath:

• Skirting boards.
• Kitchen units.
• Bathroom furniture.
• Trim.

This allows the floor to move while maintaining a neat finished appearance.

Common Misunderstandings

Conclusion

Movement joints are one of the most important yet least visible components of a successful tiled installation. They allow the natural movement that occurs within every building to take place without placing excessive stress on the tiled surface.

Although they may appear to be simple gaps, movement joints help protect against cracked tiles, failed grout and debonding, contributing to a durable and long-lasting installation. When correctly positioned and installed in accordance with recognised standards, they are an essential part of professional tiling practice.