Water, wind, and weather

Outdoor tile adhesives stand up to the elements

Outdoor tile adhesive serves structural and aesthetic purposes and is the right solution for exterior tiling projects from walls to walkways.

External floor tile adhesive protects this balcony against moisture and heat.

Defining external tile adhesives

Tile adhesives for outdoor use are formulated to withstand outdoor conditions and keep tiles in place on patios, staircases, and other surfaces. Most products are available as packages of dry material which need to be mixed.

Finding the right outdoor tile adhesive

The first step when selecting exterior tile adhesive is to verify whether it can be applied outdoors and bond to the materials being used. Some outdoor tile adhesives, such as Polybit CM 17 (a flexible tile adhesive for indoor and outdoor areas), are suitable for many materials and applications, including balconies and patios, and use in humid areas. Check the Technical Data Sheet (TDS) for details.

Polybit CM 11 is another tile adhesive for outdoor use. This adhesive mortar is suitable for different tiles like ceramic and porcelain and can be applied on both walls and floors. It’s temperature resistant up to 70°C. Polybit CM 11 is perfect for outdoor tile applications on balconies and terraces.

In addition, when selecting your product, keep in mind:

  • Some tile adhesives for outdoor use might be formulated for specific dimensions or materials. Make sure to check the label carefully before tiling.
  • Also consider whether you need a flexible exterior tile adhesive that can balance squeezing stresses on critical substrates and whether you will be using the thin-, medium-, or thick-bed method.
  • Lastly, if your surface will be subject to heavy traffic, your adhesive must be formulated for this stress.

You often need to prime absorbent surfaces with a product like Polybit CT 17 before applying your outdoor tile adhesive. Your TDS will tell you more.

Some outdoor tile adhesives are suitable only for horizontal or vertical use.

Applying flexible outdoor tile adhesive

  1. Materials. You need outdoor tile adhesive, clean water, a mixing drill, a mixing bucket, a notched trowel, and materials required for substrate preparation (see TDS).
  2. Substrate preparation. Remove all substances that could impede adhesion. Level uneven areas and roughen surfaces as stated in your product instructions. Create a slope of 2% on horizontal outdoor areas.
  3. Primer. Apply a primer, if recommended in the TDS.
  4. Mixing. Pour the amount of cool water stated in the TDS into a mixing bucket and add the contents of the mortar package. Use a drill mixer to mix the product until you have a homogeneous mass (no lumps). You may need to wait (for maturing time see TDS) and mix the mortar again or add water to achieve the desired consistency.
  5. Application. Apply exterior tile adhesive with a notched trowel appropriate for the tile size. See the TDS for minimum mortar coverage amounts and pot life.
  6. Excess removal. You can remove fresh excess mortar with water, but hardened product must be removed mechanically.