The last few years has seen a massive increase in the popularity of external tiling installations using a range of materials, but primarily external self-supported porcelain (typically 20mm porcelain), slabs, pavers and natural stone.
On method of fixing is on existing or new concrete bases.
This direct fixing method is essentially the same as internal tiling and can be used for patios, terraces or driveways.
The caveat being that expansion joints need to be incorporated into the subfloor, and falls will need to be added to ensure rainwater drains away fully.
An effective DPM should also be incorporated into any direct-to-earth subfloors – this is essential to protect the tiles from any subfloor moisture.
Where necessary, you can level the fully cured surface with an external leveller, such as BAL Level Out. BAL Level Out can mixed whereby the water content can be reduced slightly if gradient levelling has to be carried.
If a leveller is used, then protect this from adverse climatic conditions until hardened.
Once the leveller is cured, external tiles, porcelain, slabs, pavers or natural stone can be fixed using a suitable external tile adhesive – such as BAL XL Floor One.
Some external tile adhesives – such as XL Floor One – can be used directly onto tampered concrete without the use of a leveller – this may be an option if there are time or budget constraints.
Backbuttering of the tiles should always be considered – particularly on heavily keyed tiles to ensure 100% coverage.
A full contact bed of adhesive is required – as spot fixing is against British standards and leads to failures and staining.
Once the adhesive is dry, grouting can commence with an appropriate cementitious tile grout which is approved for external use.
BAL has a special high-performance Terrace Grout which has been designed to protect against the elements and high foot traffic. It is available in Dark Grey, Light Grey, Beige, and Black.