Schlüter®-DITRA-DRAIN | Notes | Schlüter-Systems



Application areas/substrates for Schlüter®-DITRA-DRAIN

General notes
Substrates on which Schlüter-DITRA-DRAIN is to be installed must always be reviewed for their suitability to make sure they are level, load-bearing, clean and compatible with the materials to be used. Remove all surface components that may weaken the bond. Uneven or sloping areas must be levelled prior to the installation of Schlüter-DITRA-DRAIN.

Interior areas
Schlüter-DITRA-DRAIN 4 is exclusively designed for use in interior areas.

Cement screeds
In accordance with the applicable regulations, cement screeds must be at least 28 days old and have a residual moisture level below 2 CM% before tiles can be installed. Nevertheless, floating screeds and heated screeds are particularly prone to curling and cracking at a later time, e.g. because of weight loads and temperature fluctuations.
With Schlüter-DITRA-DRAIN 4, tiles can be installed on freshly installed cement screeds as soon as they are ready to bear weight. Any subsequent cracking and curling of the screed will be neutralised by Schlüter-DITRA-DRAIN 4 and will not be transferred to the tile covering.

Calcium sulphate screeds
According to the applicable regulations, calcium sulphate screeds (anhydrite screeds) must have a residual moisture level of max. 0.5 CM% before tiles can be installed. With Schlüter-DITRA-DRAIN 4, the tile installation can begin as soon as the residual moisture level drops below 2 CM%. If necessary, prepare the screed surface in accordance with technical regulations and manufacturer instructions (sanding, priming). Schlüter-DITRA-DRAIN 4 can be adhered with dry-set mortars or other suitable thin-set mortars. Schlüter-DITRA-DRAIN 4 protects the screed against the penetration of moisture at the surface. Calcium sulphate screeds are sensitive to moisture, which makes it necessary to protect the screed from further water exposure such as substrate moisture.

Heated screeds
Observe the above instructions (cement, calcium sulphate) when installing Schlüter-DITRA-DRAIN 4 over heated screeds. With Schlüter-DITRA-DRAIN 4, the covering assembly is ready to heat as early as 7 days after completion. Starting from 25 °C, increase the supply temperature by a maximum of 5 °C a day to reach an operating temperature of max. 40 °C
For water-based floor heating systems, please refer to our ceramic thermal comfort floor Schlüter-BEKOTEC-THERM. Schlüter-DITRA-HEAT is a special uncoupling membrane developed for attaching the heating cables associated with electrical floor/wall heating systems; see product data sheet 6.4.

Dry screeds
Following the professional installation of the dry screed elements according to manufacturer instructions, any tile size can be used with Schlüter-DITRA-DRAIN 4.

Synthetic coverings and coatings
All surfaces must be weight-bearing and, if necessary, pre-treated, to allow for proper bonding of a suitable adhesive for permanent attachment of the Schlüter-DITRA-DRAIN 4 anchoring fleece. The suitability of the adhesive for the substrate and for Schlüter-DITRA-DRAIN 4 must be verified in advance.

Plywood panels
These materials are heavily affected by moisture (or major fluctuations in humidity). It is therefore recommended to use plywood materials with special impregnation to prevent the absorption of moisture. The thickness of the panels should be selected to ensure adequate impact resistance in conjunction with suitable support structure. Plywood panels must be sufficiently attached with screw connections. All seams should either be tongue-and-groove connections or covered with adhesive. Edge joints of approx. 10 mm must be kept open at the transitions to adjoining building components. Schlüter-DITRA-DRAIN 4 neutralises the stresses in the tile covering and also prevents the penetration of moisture.

Hardwood floors
The direct installation of ceramic coverings over hardwood floors is generally feasible, provided the floorboards have tongueand- groove connections, are sufficiently load-bearing, and are tightly screwed down. The wooden substrate should have reached a balanced moisture level before Schlüter-DITRA-DRAIN 4 is installed. Experts recommend the installation of an additional layer of plywood. Uneven floors must be levelled with suitable measures.

Mastic asphalt
Schlüter-DITRA-DRAIN 4 enables the installation of ceramic tile coverings on standard weight-bearing, unheated mastic asphalt screeds in indoor areas. Surfaces must be sanded and allow for proper bonding of the thin-set mortar to adhere Schlüter-DITRA-DRAIN 4.

Outdoor areas
In outdoor areas, Schlüter-DITRA-DRAIN 8 is particularly suited for stairs and larger balcony and terrace areas with extended drainage paths. Schlüter-DITRA-DRAIN 4 may be used for smaller areas with drainage paths or sloped stretches up to approx. 3 m. If the installation substrate does not require a waterproofing assembly, e.g. in case of a drainage screed or direct installation over open soil, Schlüter-DITRA-DRAIN can also be adhered directly to the substrate with thin-set mortar for drainage/subaeration and uncoupling.

Balconies / terraces
As an uncoupling and drainage membrane, Schlüter-DITRA-DRAIN neutralises the stresses between the substrate and the tile covering that are caused by frequent, major temperature changes on balconies. Moreover, Schlüter-DITRA-DRAIN protects the bonded waterproofing assembly and enables fast curing of the thin-set mortar by providing subaeration for the covering. The bonded waterproofing assembly – e.g. Schlüter-KERDI 200 (see product data sheet 8.1) – must have a sufficient slope of 1.5 to 2%. The existing covering assembly may be directly used as a substrate for renovation projects if the old covering is adequately weight-bearing and has the necessary slope. Otherwise, remove any loose or insufficiently attached parts and level defective areas and absent sloping with a suitable ready-mixed mortar prior to installing the bonded waterproofing assembly.

Schlüter-DITRA-DRAIN 8 is suitable as an uncoupling and drainage membrane on staircases in outdoor areas to reduce stresses between the substrate and the tile covering and to channel accumulating water in the drainage area. Moreover, Schlüter-DITRA-DRAIN 8 protects the bonded waterproofing assembly Schlüter-KERDI 200 (see product data sheet 8.1) and enables fast curing of the thin-set mortar by providing subaeration for the covering. The bonded waterproofing assembly must have sufficient slope in the stair step area.
Carefully check that the Schlüter-DITRA-DRAIN 8 membrane adhered to the riser does not protrude over the surface of the stair step so any accumulating water can drain off completely. Cover any abutting seams with the seaming tape Schlüter-DITRA-DRAIN-STU. Drainage water accumulating at the foot of the stairs must be able to seep out of Schlüter-DITRA-DRAIN 8 into a drainage space or flow into a drain. In the exposed edge area of the staircase, a 5 cm wide strip of 9 mm Schlüter-KERDI-BOARD (see product data sheet 12.1) can be installed in the drainage area together with a tile strip as a water barrier or splash guard on the covering, using the sealing adhesive Schlüter-KERDI-COLL-L (see product data sheet 8.4).
We recommend using the corresponding stair-nosing profiles (e.g. Schlüter-TREP-E) at the front of the steps to protect the edges of thinner covering material and to improve anti-slip properties.

Roof terraces
In accordance with the applicable technical regulations for roof structures, the surfaces of roof terraces over residential/ commercial or other spaces as well as roof-covered surfaces have to be designed as a flat roof.
In the case of heat-insulated residential and commercial spaces (as well as spaces with expected temperature differences to the outside), a vapour barrier as well as ceiling insulation are required for compliance with building codes. National standards and/or the applicable technical data sheets have to be observed. A drainage membrane (e.g. Schlüter-TROBA or Schlüter-TROBA-PLUS, see product data sheet 7.1 or 7.2) must be installed above the top waterproofing layer, followed by a screed layer on top as a load-distribution layer. Schlüter-DITRA-DRAIN is adhered to the surface of the screed for uncoupling and subaeration of the tile covering and to protect the screed against moisture. The uncoupling membrane Schlüter-DITRA-DRAIN neutralises the stresses between the substrate and the tile covering that are caused by frequent, major temperature changes on terraces.

Movement joints
Schlüter-DITRA-DRAIN must be separated above existing movement joints. Movement joints must be incorporated into the tile covering in accordance with the applicable regulations and standards. In outdoor areas (balconies and terraces), the length of the individual fields should not exceed 3 m. Smaller fields may be necessary, depending on the substructure and the expected temperature fluctuations.
Suitable edge joints must be formed at connections to upright building elements or walls to reduce the build up of stresses. The edge joints and connection joints must meet the applicable professional regulations. The frequency must be sufficient to reduce the build up of tensions. The use of the various profile types of the Schlüter-DILEX series is recommended for constructing movement joints and edge joints.

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Units 3-5 Bardon 22,
Beveridge Lane, Coalville,
Leicestershire, LE67 1TE
Phone: +44 (0) 1530 813396

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