Installing Outdoor Tiles on Concrete Bed

27 September 2022

The technique for installing outdoor tiles is like that of putting inside tiles. However, the process may not be the same when it comes to installing tiles on a concrete surface in outdoor areas like alfresco or patio. The purpose of this article is to describe how to install outdoor tiles over an existing concrete bed. 

Image Source: Ruslan Sidorov / Getty Images

The kind of outdoor tiles that can be used:  

For patios or alfresco where you expect medium to heavy footfall (of gatherings and parties), and you host barbeque dinners, it is advisable to install Granite or Bluestone Tiles. Both these natural stone tiles are known for their resilience and do not get affected by heat, dragging of heavy furniture, or wear & tear.  

In case the traffic you expect is low, then go for Travertine or Limestone Tiles. Though the stones have enough durability, they are not as resilient as Granite. These stones are popular for their subtle colours and excellent aesthetic value.  

Marble tiles for outdoors are a luxurious option if you want to add an unmatched elegance to your outdoor space. However, install slip-resistant tiles instead of polished ones that increase the chances of slipping hazards.  

No matter what tiles you install outdoors, ensure sealing them in the end to preserve their look and protect the surface from damage. Irrespective of the type of stone tile, please ensure their thickness is more than 12 mm. Travertine’s thickness starts from 12mm while other stones like Granite and Marble start from 15mm. Any tile with thickness less than this might break or crack under footfall.  

Steps of Preparation 

  1. Please ensure that every surface is sound and spotless. Inspect concrete patios for cracks or aging concrete. Fix any loose concrete and patch any cracks. Use a concrete wash to clean the concrete before installation. Floored areas must be level.
  2. A solution for levelling floors will eliminate slight surface dips. If your patio area has substantial dips, numerous fractures, or is very uneven, you might need to construct a subbase over the current concrete. A sub-base is a layer of floor-mix concrete that forms a level, durable surface.
  3. You should consider an underlayment for strength and stability. This will reduce the roughness of the concrete surface and any chances of the tiles cracking. This can be achieved by a cement board or a backer board. These boards protect the flooring material from moisture damage while adding stability to tiles.  

Homeowners often ask if they can install tiles directly over concrete. The answer is yes, you can. However, there are contractions and expansions in the floor which may cause the tiles to crack or shift, ruining the newly installed tiles.  

Tools you should get for the installation process 

Before you begin laying the tiles, make sure you have all the necessary tools. Since outdoor patio tiles are thicker than inside floor tiles, you will need a wet saw to cut the tiles. Gather these tools for the installation process-  

  1. A bucket to mix concrete and fill holes if any
  2. Trowel
  3. Broom
  4. Scrub brush
  5. Dustpan
  6. Concrete sealer
  7. Concrete fixing compound
  8. Roller with a longer handle
  9. Cloth or towels to remove stains or dust 


  1. Plan the outdoor tile arrangement to reduce cutting. You must arrange the tiles such that they do not hide the expansion joints if your current concrete slab has them. Rather, align the grout line with the joint line.
  2. If covering the expansion joints with tiles is not an option, the concrete must first be covered with a flexible membrane before the tiles are put in place. To avoid the mortar from drying up too quickly, place the tiles with an exterior-grade thin-set mortar while working in small sections at once.
  3. Apply mortar to the concrete and the tile's back to stop air pockets from forming beneath the tiles. To achieve strong bonding, lightly tap the tiles with a rubber mallet as you set them into place. 
  4. To ensure the floor tiles stay firmly in place by using thin-set (modified) mortar. This kind of adhesive will create an extremely strong bond that will cause minimal to no shrinkage. This means there would be fewer chances of cracks and will preserve the look of the floor for a long time. 
  5. Remove any extra mortar or spacers once all the tiles have been installed. For about a day or so, until the mortar is set, cover newly installed floor tiles with plastic sheeting. This stops rain or dew from collecting between the tiles. 


1.Porous tile should be sealed with acrylic grout. Apply the sealant solely to the tile tops using a paintbrush. Sealants create a protective layer on tiles, preventing dust or grime build-up and moisture from entering the concrete below.  

Tip: It is important to wait at least 24 to 48 hours after tiling before grouting the tiles. This helps to cure the surface adhered to the tiles with mortar.  

2. Insert a caulk backer rod between the tiles along the expansion joint line if you designed your tile arrangement to take use of an existing concrete expansion joint.  

3. To grout, the tiles, combine an exterior-grade grout with an additive that has latex in it. Remove any extra grout from the tiles, then wait for it to dry. When the grout has dried but before it has cured, remove the caulk backer rod. With latex caulk that is coloured to match the grout, fill up the space left by the backer rod. The cured grout should be sealed with acrylic grout. 

The final word  

Outdoor tiles are exposed to standing water depending on the surface and the weather. The risk increases if the area receives heavy rainfall or has a poor drainage system. This clearly implies it's imperative to keep any air voids under the tile to a minimum. Water may enter air pockets beneath the tiles, weakening the adhesive and raising the possibility of tile collapse. Following these instructions will ease the installation process to a great extent. If you are installing natural stone tiles like Travertine, Marble, or Slatestone, check the slip-resistance and durability.

Stone Depot is one of the largest Importer and Distributor of Natural Stone in Australia from India, Turkey, China, Brazil with over 30 years of experience. We import high-quality stones with primary focus on timely delivery of products at a very competitive pricing.