Laying tiles - Drainage explained simply!

The Subsoil

Without the right substrate, which forms the basis for the final result, nothing works. Basically, you can lay tiles on any substrate, however, the factors of appearance and preventing damage from moisture play a major role! But beware! Different floors = different properties. This means that the respective preparatory work must be individually adapted to the respective substrate.

Generally speaking: The substrate must be firm, load-bearing, dust-free and dry. The surface should be even and any cracks must be filled.

Possible problems that may occur:

Waterlogging

Due to errors in the sealing slope, such as elevations in the overlap area or unevenness, water can accumulate under tile coverings.

Frost and heat

When laying ceramic floors outdoors, for example on balconies or terraces, tile coverings are exposed to high thermal stresses, which can lead to long-term damage in the floor structure.

Cracks in the pavement structure

These lead to severe moisture penetration into the flooring, accompanied by tile detachment, hollow spaces, efflorescence, and structural damage.

The solution: Drainage mats

The DURABASE DR 100++ drainage mat is a highly dimensionally stable and pressure-resistant, closed-cell polypropylene sheet with a dimpled structure, equipped with a laminated mesh fabric. The dimpled side with the mesh fabric, on which the covering structure rests, acts as a drainage layer with very high water conductivity. The truncated cone-shaped dimples and their varying heights allow for a sufficiently large drainage capacity even under heavy loads. The material is rot-proof and age-resistant. Remnants can be disposed of with normal household waste.

The flooring constructions with DURABASE DD 80 ++ can be chosen very flexibly and thus offer a maximum degree of adaptability to the respective object:

1. Laying under drainage screed
2. Installation in a gravel/crushed stone bed
3. Relocation in trestle bearings
4. Direct laying

Use of drainage mats

Drainage mats are used in outdoor installations, especially where sealed surfaces are involved. DURABASE DR 100++ is particularly suitable for creating large-area drainage systems in combination with tiles, slabs, natural stone and concrete slabs, as required for example on balconies, terraces, pavements, swimming pool surrounds, etc.

If you want to lay drainage mats under tiles, the drainage mats are glued between the substrate and the tile covering. Tiles can be easily laid on the mats. However, drainage mats do not replace the substrate sealing. The substrate on which the mats are to be laid must also be sealed separately. Our blog post " Laying Tiles - Sealing Explained Simply " can help you here. In addition, it must also have a sufficient slope so that the water collected in the mats can drain away quickly.

Function as a decoupling mat

Another important benefit – besides water drainage – is that drainage mats always also function as decoupling mats . They effectively decouple the tile covering from the substrate, thus helping to prevent stress cracks and movements of the tile covering with subsequent cracks in the grout.

Drainage or water drainage?

Basically, the most important factor for using a drainage system is the type of surface covering the terrace. There are two major differences:

1. water-permeable surface (such as permeable paving stones or similar)
2. water-impermeable concrete (such as laid natural stone tiles or non-percolating paving stones in the concrete bed)

With a permeable pavement, surface water seeps through the pavement into the subbase. From there, it should also seep into the ground as quickly as possible. If water accumulates in the subbase, this can lead to damage to the subbase due to frost and the constant water level. The decisive factor for a possibly necessary drainage of the subbase through drains is the soil type. Heavy or cohesive soils (such as very clayey soil types) allow water to seep through only slowly. In this case, additional drainage must be provided.

With a waterproof surface, not only should the surface itself be drained (in many places, this is even mandatory for driveways), but also the substructure, if possible. This prevents damage to the substructure caused by penetrating water. For example, water can seep through tile joints over longer periods of time. If drainage mats are installed below the surface, penetrating water can be drained away relatively quickly. In addition, the surface (e.g. tiles) is effectively decoupled from the substrate. This also helps to avoid stress cracks.

The use of drainage mats under natural stone paving is particularly recommended. They are also available for loosely laid paving. In these areas, they then also replace any necessary adjustable supports.

Installation instructions

1. The properly prepared substrate must be load-bearing, even and free of components that could damage the building seal. Any leveling measures to achieve a sufficient slope must be carried out before laying DURABASE DD 80++ and must be located below the building seal.
2. Lay the sheets, cut to size, loosely on the building waterproofing with the mesh fabric facing upwards.
3. Adhere mats to each other edge-to-edge with the self-adhesive grid tape DURABASE WB to ensure shear resistance.
4. Seal wall connections with DURABASE WP ++ sealing tape if necessary. The sealing tape is partially glued to DURABASE DD 80 ++ and the adjacent wall surface using flexible adhesive. For most substrates, a hydraulically setting flexible adhesive or a fast-setting flexible adhesive according to DIN EN 12004 / C2 can be used. Internal and external corners should be formed using the appropriate DURABASE Flex corner pieces.
5. Then, apply the chosen pavement structure in accordance with the specific requirements and according to generally accepted engineering principles.

Notes:

In general, the generally accepted rules of technology must be observed!

For all products/materials: The suitability for mechanical and chemical stress must be carefully checked in each individual case before laying the mat. Protect material from prolonged exposure to sunlight.

If you should have any further questions, please feel free to contact us.

Best of luck with the tiling!

The team from Everything for Tiles