Schlüter®-DITRA-HEAT | Function | Schlüter-Systems


Application and Function

Schlüter®-DITRA-HEAT is a polypropylene membrane with a cut-back stud structure and an anchoring fleece laminated on the underside. It is a universal substrate for tile coverings, which serves as an uncoupling, crack bridging, waterproofing, vapour pressure equalization layer and is designed for the attachment of heating cables.

Schlüter®-DITRA-HEAT-DUO features a 2 mm special anchoring fleece on the underside, which bonds with the adhesive, while also reducing impact sound and enabling a faster heat-up response. The substrate for the installation of Schlüter®- DITRA-HEAT must be level and ready to bear weight. Schlüter®-DITRA-HEAT is installed in thin-bed adhesive suitable for the substrate with a notched trowel (recommended size: 6 x 6 mm). The anchoring fleece on the underside of Schlüter®-DITRA-HEAT is then fully embedded in the adhesive to ensure a mechanical bond of the fabric in the adhesive. The curing window of the adhesive has to be taken into consideration. In floor areas, the heating cables can be installed immediately after adhering Schlüter®-DITRA-HEAT matting with a minimum spacing of 9 cm (every third stud ≙ 136 W m²).

In the case of wall installation, the heating cables are installed once an adequate adhesive bond has been reached. Installers can choose between installation spacing of 6 cm (every second stud ≙ 200 W m²) and 9 cm (every third stud ≙ 136 W m²). The tile or stone covering is professionally installed directly over Schlüter®-DITRAHEAT membrane in accordance with the applicable standards. The bed adhesive bonds with the cut-back stud structure of the Schlüter®-DITRA-HEAT membrane.

Schlüter®-DITRA-HEAT / -HEAT-DUO is waterproof and can withstand all chemical stresses that typically occur in conjunction with tile coverings. Where required, an approved bonded waterproofing assembly can be created with Schlüter®-DITRA-HEAT / -HEAT-DUO in specific areas.

The cable tester Schlüter®-DITRA-HEATE-CT is designed to measure and verify the resistance of the electrical heating cables Schlüter®-DITRA-HEAT-HK and the remote sensors included with the thermostats Schlüter®-DITRA-HEAT-E. The device monitors the resistance of the heating cables during the entire installation phase. An acoustic signal will sound to alert the installer in the event of damage.

Summary of functions

a) Uncoupling
Schlüter®-DITRA-HEAT uncouples the covering from the substrate and neutralise’s stresses between the substrate and the tile or stone covering that result from different deformation processes. The material effectively bridges tension cracks from the substrate and ensures that they are not transferred to the tile covering.

b) Waterproofing
Schlüter®-DITRA-HEAT / -HEAT-DUO is a waterproof polyethylene membrane with a relatively high water vapor diffusion seal. When properly installed at the abutting seams as well as at wall transitions and connections to building components, Schlüter®-DITRA-HEAT / -HEAT-DUO can form part of an approved bonded waterproofing assembly with the tile covering. Schlüter®-DITRA-HEAT / -HEAT-DUO can be used in accordance with the German waterproofing standard DIN 18534. Water exposure classes: W0-I to W3-I*. Furthermore, Schlüter®-DITRA-HEAT / -HEAT-DUO features the national technical approval (abP) required in Germany.

Moisture load class according to ZDB: 0 to B0 and A.

Schlüter®-DITRA-HEAT / -HEAT-DUO features European Technical Approval (ETA) pursuant to ETAG 022 (watertight covering kits) and bears a CE mark. It must be ensured that only system-approved thin-set mortars are used in areas that require CE conformity or compliance with the general certificate of national technical approval. Please contact the address specified in this data sheet for further information on suitable thin-set mortars and the corresponding test certificates.

Schlüter®-DITRA-HEAT / -HEAT-DUO therefore protects the substrate from damage that results from permeating moisture and aggressive substances.

* With abP and/or in compliance with ETA according to ETAG 022. Please contact our Application Technology department for further information regarding use and installation.

c) Load distribution (load induction)
Tiles that are installed in floor areas over Schlüter®-DITRA-HEAT should at a minimum have a size of 5 x 5 cm and a thickness of 5.5 mm. The indentations of Schlüter®-DITRA-HEAT with their thinbed mortar filling transfer the traffic loads impacting the tile covering directly to the substrate. This makes tile coverings installed over Schlüter®- DITRA-HEAT especially durable. If high traffic loads are expected (e.g. in commercial areas) or if the floor must accommodate large point loads (such as grand pianos, fork lifts, shelf systems), the selected tiles must feature the necessary thickness and pressure stability for the corresponding application area. In Germany, the guidelines of the information sheet “Ceramic floor coverings for high mechanical impact” must be observed for tile thicknesses.

Tiles must be fully embedded in the tile adhesive in areas with high traffic loads. Please note that the contact surface of Schlüter®-DITRA-HEAT is approximately 50% of the entire area, which may cause a corresponding reduction in pressure resistance in the presence of high point loads. Schlüter®-DITRA-HEAT-DUO features a special 2-mm anchoring fleece on the underside and can be used for traffic loads up to 3 kN/m². This includes residential and commercial premises with light foot traffic (residential buildings, office and administrative spaces, restaurants, hotels, conference rooms, nursing stations and patient rooms etc.)

As a rule, the impact of hard objects must be avoided on ceramic coverings for both Schlüter®-DITRA-HEAT and Schlüter®-DITRA- HEAT-DUO. Tiles should have minimum dimensions of 5 x 5 cm.

d) Bonded assembly
Due to the bond of the fleece fabric with the thin-bed adhesive over the substrate and the mechanical anchoring of the thinset screed in the cut-back stud structure, Schlüter®-DITRA-HEAT creates a lasting bond of the tile covering with the substrate. Schlüter®-DITRA-HEAT can therefore be used in wall and floor areas.

e) Thermal separation
Schlüter®-DITRA-HEAT-DUO features a 2 mm special anchoring fleece on the underside, which bonds with the tile adhesive, while also reducing impact sound and enabling a faster heat-up response. f) Sound insulation An impact sound insulation improvement (ΔLW) of 13 dB was measured in a full installation of Schlüter®-DITRA-HEAT-DUO (in accordance with DIN EN ISO 10140). However, the actual impact sound reduction of an assembly depends on local circumstances (construction system) and may differ from this value. Consequently, the determined test values cannot be applied generally to all construction site situations.

Contact Schlüter-Systems Ltd

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

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