What Types of Adhesives are Best for Terracotta Tiles?

Cement-Based

There are a range of cement-based adhesives on the market that are suitable for use with terracotta tiles. This provides the thicker, sturdier base that is needed for the heavy tiles to lay on. One type is made from a mixture of cement and sand to create an even firmer base. A cement-based adhesive can be problematic due to the porous nature of terracotta tiles, which can allow water through to the extent that it reacts with the cement and affects the finish of the tile.

Powder

Powder adhesives are widely available from do it yourself stores and in an array of colors, which will allow you to match it to the terracotta tiles so that it is not noticeable if it is seen. The powder comes in bags of different sizes, with the largest one usually proving to be the most cost effective. Even if the entire contents of a large bag are not required, this can still be a convenient purchase to complete the job. The amount of powder necessary to mix a sufficient batch of glue can be transferred to a container to be mixed with water, while the remainder is stored in an airtight manner to be used for another task at a later date. This will allow you to mix it to a thick enough consistency to support the tiles properly, which will be up to about an inch.

Mastic    

Mastic is a synthetic substance that can be used on a range of different types of tile for the purposes of gluing and filling. The volume of mastic needed for the task must be separated so that it can be mixed with a hardening solution before it is applied; this will make the adhesive more effective. The temperature of the room in which the tiles have been laid will affect the length of time it takes for the mastic to dry. Mastic is an ideal substance to use as a filler because it dries solid enough to enable it to be polished.  

PVA

If you are laying terracotta tiles atop other tiles then a PVA type glue can be used for this purpose. It will be necessary to thoroughly clean the surface before applying any glue to it. This type of glue is relatively cheap and widely available from hardware stores.      

Ready-Made

Tubs of ready-mixed liquid adhesive are available that are suitable for all types of flooring, whether being laid inside or outside. They are often designed to be quick drying, and it becomes waterproof as soon as it has dried. They conveniently come in tubs to make them ready to use the moment the lid is taken off and they do not require any mixing. Making sure the lid is securely replaced after use will enable it to be saved for later.

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