The complete guide to tile thickness: choosing the right thickness for every application

Tile thickness refers to the measurement from the top surface to the bottom surface of a tile; when it comes to porcelain stoneware applications, it typically ranges from 6mm to 20mm. This dimension is crucial in determining where and how tiles can be installed as both structural stability and visual appeal are closely linked to this parameter.

The thickness of your tiles affects three key factors: durability, installation method, and suitability for specific applications. Thicker tiles generally provide greater strength and better resistance to heavy loads, making them ideal for high-traffic areas and outdoor installations. On the other hand, thinner tiles offer advantages in renovation projects and wall applications, where a lighter weight is essential.

20mm thick porcelain tiles outdoor terrace installation with stone effect finish. — Discovery Ardesia Silver

Discovery ardesia silver — Discovery Ardesia Silver

Porcelain stoneware thickness: consistent performance across all options

Unlike traditional ceramic tiles, which can experience performance variations when thickness changes, porcelain stoneware maintains its exceptional technical properties consistently across all thickness options. This reliability stems from porcelain stoneware's superior composition and manufacturing process. Premium raw materials are fired at extremely high temperatures up to 1235°C (2255°F). This process creates a uniformly dense and non-porous material.

Whether you choose 6mm for wall applications or 20mm for heavy-duty outdoor use, porcelain stoneware retains its fundamental characteristics. These include low water absorption below 0.5%, stain resistance, color stability, and durability.All thicknesses maintain identical performance while being optimized for different installations.

Three main tile thickness options

With porcelain's consistent performance characteristics established, let's explore the three main thickness options available and their specific advantages.

6mm tiles: renovation & walls

The 6mm thickness represents the thinnest option in porcelain stoneware collections, specifically designed for renovation projects and weight-sensitive applications. These ultra-thin tiles excel in situations where existing floors cannot be removed, allowing direct installation over current surfaces without significant height increases. This thickness is particularly advantageous for wall coverings, where reduced weight minimizes structural stress and simplifies installation processes, making them perfect for interior wall applications.

9mm tiles: standard indoor

The 9mm thick tiles represent the most widely used option for indoor flooring applications. They offer the optimal balance between porcelain stoneware's inherent durability and practical installation requirements. This standard thickness provides excellent resistance to daily wear while remaining suitable for most residential and commercial interior installations. The 9mm format offers optimal performance for living areas, bedrooms, and moderate-traffic commercial spaces. It works exceptionally well with underfloor heating systems while providing efficient heat transfer.

20mm tiles: outdoor & heavy duty

20mm thick tiles maximize porcelain stoneware's inherent strength. They enable exceptional resistance to extreme conditions and substantial loads. These robust tiles are specifically engineered for outdoor applications. They offer superior resistance to weather, frost, and thermal shock while providing exceptional impact resistance for high-traffic commercial areas and vehicular applications. What truly sets them apart is their ability to be installed using dry-laying methods over grass, gravel, or sand. This eliminates the need for traditional adhesive installation, making them ideal for terraces, pool decks, and outdoor walkways.

6mm thick porcelain wall tiles installation large format beige finish. — Geo Grey

Wall tile thickness

Wall tile installations require careful consideration of several key factors when selecting appropriate thickness. Weight distribution stands as the primary concern, as wall structures have limited load-bearing capacity compared to floors. This makes 6mm thickness the optimal choice for most applications. This ultra-thin format reduces structural stress while maintaining porcelain stoneware's superior technical properties. These include moisture resistance, stain resistance, and color stability. Additional considerations include installation complexity, adhesive requirements, and aesthetic goals such as minimal grout lines and seamless surfaces. The reduced profile tiles also ensure compatibility with electrical fixtures, plumbing connections, and architectural details common in wall installations.

9mm thick porcelain floor tiles installation wood effect finish. — Unica Honey

Indoor floor tile thickness

While wall installations prioritize weight considerations and moisture resistance, floor applications focus on durability and load-bearing capacity, requiring different thickness considerations. Indoor flooring applications establish 9mm as the standard thickness for porcelain stoneware installations. This represents the optimal balance between performance, durability, and practical installation requirements. This thickness has become the industry benchmark for residential and commercial interior floors. It has proven ability to withstand daily foot traffic while maintaining structural integrity under typical furniture loads. The 9mm format provides sufficient material density to resist surface wear, impact damage, and thermal stress. It remains compatible with standard installation methods, door clearances, and underfloor heating systems that require efficient heat transfer.

20mm thick porcelain outdoor tiles installation neutral finish. — Trevi Walnut

Outdoor porcelain tile thickness

Indoor floor installations have different requirements than exterior applications, which face extreme weather conditions, ground contact, and often vehicular loads that demand the most robust thickness solutions. Outdoor tiles must contend with unique challenges including direct ground contact, drainage requirements, and pedestrian or vehicular traffic that require enhanced durability specifications. Heavy-duty outdoor applications require 20mm thick tiles to withstand extreme loads, vehicular traffic, and intensive use conditions. They excel in commercial plaza installations, parking areas, pool decks, and public walkways where durability and safety are paramount.

The substantial thickness provides exceptional impact resistance and superior load distribution. It also enables specialized installation methods including dry-laying over sand, gravel, or grass surfaces. This eliminates traditional adhesive requirements and simplifies maintenance procedures while supporting vehicles and heavy equipment without compromising structural integrity or visual appearance.

Visualizing your project with Match App

Your thickness choice ultimately depends on three factors: location (indoor vs. outdoor), load requirements (foot traffic vs. vehicles), and installation constraints (renovation vs. new construction). For indoor floors, 9mm provides optimal performance. For walls and renovations, 6mm offers practical advantages. For outdoor and heavy-duty applications, 20mm ensures maximum durability. To see how your selected thickness will look in your actual space, use our tile layout planner Match App to visualize different options and confirm your choice meets both technical and aesthetic requirements.