Essential Expansion Joints: Why Every Tile Installation Needs Them

Every tile installation—ceramic, porcelain, stone, glass, or concrete—requires properly designed and placed expansion (movement) joints to prevent damage caused by the natural movement of tile assemblies. Expansion joints accommodate expansion and contraction due to changes in temperature, humidity, or moisture, and also allow for structural shifts, ensuring the long-term stability and durability of the tile surface.

Without these joints, stress from movement can lead to several serious issues:

• Cracking of tiles or grout if the tiles are otherwise well bonded but lack movement relief.

• Tenting, lifting, or unevenness when tiles are not sufficiently bonded to the substrate.

• Moisture infiltration through cracks, which can damage neighboring materials, especially in wet areas.

• Premature installation failure, frequently due to the compounding effect of omitting expansion joints.

Types of Expansion Joints:

• Full-depth expansion joints: Run through the tile, mortar, and reinforcing layers down to the substrate.

• Perimeter joints: Placed wherever tile meets a wall or other restraining surface.

• Intermediate (in-field) joints: Used for large areas or over control joints in substrates.

Standard Placement Guidelines:

• Exteriors and areas with direct sunlight or moisture: Joints every 8–12 feet in each direction.

• General interiors: Joints every 20–25 feet.

• All perimeters, transitions, and changes of plane: Must include movement joints, such as along walls or where floors meet columns, curbs, or other surfaces.

• These standards are detailed in the Tile Council of North America’s (TCNA) EJ171 Movement Joint Guidelines.

Materials for Joints:

• Use only high-quality, flexible sealant that meets ASTM C920 standards: silicones, urethanes, or polysulfides are preferred, as they provide durability and lasting performance. Avoid siliconized, acrylic, or latex sealants as they do not perform well long-term.

Professional Responsibility:

• Industry standards require movement joints, making their omission not just a technical oversight but a significant liability risk. Architects or engineers must specify the type and

  location of joints. If no professional is assigned, follow industry standards explicitly, and ensure clients are informed about these mandatory requirements.

In summary, expansion joints are not optional; they are critical engineering details that protect tile installations from common, preventable failures caused by inherent structural and environmental movement.