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 equalisation 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 DITRA-HEAT must be level and ready to bear weight. Schlüter-DITRA-HEAT is installed in thinbed adhesive suitable for the substrate with a notched trowel (recommended size: 6 x 6 mm). The anchoring fleece on the underside of 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 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 use of mats is recommended for wall areas. The tile or stone covering is professionally installed directly over DITRA-HEAT membrane in accordance with the applicable standards. The bedding adhesive anchors with the cut-back stud structure of the 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 DITRA-HEAT / -HEAT-DUO in specific areas.

Use the cable tester Schlüter-DITRA-HEAT-E-CT to measure the resistance of the electrical heating cables DITRA-HEAT-E-HK and the remote sensors included with the thermostats 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. The DITRA-HEAT-E-CT switches off automatically approximately 1 hour after the last “keystroke”.

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 polypropylene membrane with a relatively high water vapour diffusion seal. When properly installed at the abutting joints as well as at wall transitions and connections to building components, 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, 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 tile adhesives 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 tile adhesives 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 DITRA-HEAT should at a minimum have a size of 5 x 5 cm and a thickness of 5.5 mm. The indentations of DITRA-HEAT with their tile adhesive filling transfer the traffic loads impacting the tile covering directly to the substrate. This makes tile coverings installed over 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 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 DITRA-HEAT and 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 thin-set adhesive in the cut-back stud structure, 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 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.

Installation

The system may only be installed by a certified electrician (EN 60335-1). This heating cable must feature a multi-pole circuit breaker with a contact clearance of at least 3 mm per pole. To protect against inadvertent contact, an RCD (FI circuit breaker) with a tripping current of IΔN ≤ 30 mA must be installed. Further information about installing the heating cables and installing and setting the thermostat is included in the instructions supplied with the heating cables or the thermostat.

Positioning the floor sensor

Variant A: The floor sensors are positioned directly in the newly installed uncoupling membrane DITRA-HEAT. Since the floor sensors are directly embedded in the adhesive and cannot be replaced, the installation should include a spare sensor (a second sensor is included with the thermostat as a spare). The sensors must be installed centrally between two heating cable loops.

Variant B: The thermostat floor sensor is positioned in the conduit with the sensor sleeve directly in the floor underneath the uncoupling membrane DITRA-HEAT. Make a cut out in the uncoupling membrane DITRA-HEAT in the area of the sensor sleeve. Insert the sensor into the conduit and then slide the sleeve over it (conduit and sensor sleeve are included in the installation set Art. No. DH EZ S1). To guarantee optimum temperature transfer from the area to be heated to the sensor, no insulation material (e.g. DITRA-HEAT-DUO) should be located between the sensor sleeve and DITRA-HEAT. In this case, a cut out for the sensor sleeve should be made in the insulation.

Note: Prior to embedding the sensors in the adhesive, measure the resistance values, for example with the cable tester DITRA-HEATE-CT, and compare them to the values listed in the thermostat instructions.

1. The substrate must be level, load-bearing, and free of any substances that may weaken the bond. All levelling work must be completed prior to installing Schlüter-DITRA-HEAT.
    
2. The adhesive used for installing DITRA-HEAT must be selected to suit the substrate type.
   
   The adhesive must bond well with the substrate and mechanically set in the anchoring fleece of DITRA-HEAT. Check for any incompatibilities of materials.
   
   It is therefore advantageous to prepare the thin-set tile adhesive in a fluid-bed consistency. Check for any incompatibilities of materials. If using covering materials with a lateral length ≥ 30 cm, we recommend a water-binding tile adhesive for rapid curing and drying of the mortar.
    
3. Apply a suitable adhesive on the substrate with a notched trowel (6 x 6 mm). To achieve a better initial bond for adhesion in wall areas, we recommend applying a contact layer on the backside of DITRA-HEAT.
    
4. Cut pieces of DITRA-HEAT to size and fully embed the anchoring fleece in the applied adhesive. Immediately press the material into the adhesive with a float or a roller, working in a single direction. The curing times of all materials must be observed. When installing materials from a roll, it is best to align DITRA-HEAT with light tension at the time of positioning the material. The Easycut gridlines minimise the curling memory of the membrane. Mats are recommended for wall applications for easier handling. The mats or membranes are installed with closely abutting joints.
    
5. To prevent damage or detachment from the substrate, it is recommended to use timber boards (especially in the centre of the assembly for material transport) to protect the installed DITRA-HEAT membrane from mechanical impact.
    
6. Installation of heating cables
   6a. The heating cables can be installed immediately after adhering the DITRA-HEAT uncoupling membrane, using a float or roller. In the case of wall installation, the heating cables are installed once an adequate adhesive bond has been achieved. Heating cables may not touch or cross one another.
   
   6b.Prepare a groove in the area of the soldered cable end.
   
   Note: The cable tester DITRA-HEAT-E-CT is designed to continuously measure the resistance of the electrical heating cables DITRA-E-HK during the entire installation phase. An acoustic signal will sound to alert the installer in the event of damage.
   
   Floor areas:
7. The stud spacing of the uncoupling membrane is 3 cm. Spacing in floor areas must be at least 9 cm (installation around every 3rd stud–equivalent of 136 W/m²), spacing may not be closer. Closer spacing, especially in floor areas, may result in overheating and damage to building structures. Make sure not to step on heating cables during the installation work.
   
   Wall areas:
8. Depending on the available space, the desired surface temperature and the required heating output, the installation spacing in wall areas can either be
   • 6 cm (around every second stud– equivalent of 200 W/m²) or
   • 9 cm (around every third stud–equivalent of 136 W/m²).
    
9. The transition from the heating cable to the connection cable (sleeve) is labelled with an imprint as shown. The sleeve also features a “Connection” label. The imprint “COLD” is shown in the further course of the connection cable. This ‘cold leg’ (4 m) must be connected directly to the junction box or thermostat. The ‘cold leg’ can be shortened to max. 1.00 meter in front of the sleeve, but heating cables may not be cut to size.
    
10. Once the heating cables have been installed and tested in accordance with the DITRA-HEAT-E installation instructions, tiles can be installed, using an adhesive that meets the requirements of the covering. It is helpful to fill the grooves of the uncoupling membrane in a single step, using the smooth side of the notched trowel (heating cables and sleeves must be fully embedded in tile adhesive) and to then use the notched side to prepare the adhesive for the tile or stone. To ensure full embedding in the adhesive, choose a notched trowel to match the tile format. The curing times of the adhesive must be observed.
     
11. Please observe the instructions regarding movement joints as perimeter, edge and connection joints in this product data sheet.

Note:

The adhesive and the covering materials used in conjunction with DITRA-HEAT must be suitable for the corresponding application and meet the applicable requirements. The first heating of DITRA-HEAT may not occur any earlier than 7 days after completion of the covering assembly.

Waterproofing with Schlüter®-DITRA-HEAT

Provided the panel joints and the connections to built-in elements and upright structural fixtures are carefully sealed, Schlüter-DITRA-HEAT can be used to create a certified bonded waterproofing assembly with the tile covering.

Schlüter-DITRA-HEAT features the national technical approval (abP) required in Germany and bears the Ü mark. Moisture exposure class according to abP: 0 - B0 und A. Schlüter-DITRA-HEAT has the required European Technical Assessment (ETA) as specified in ETAG 022 (bonded waterproofing assemblies) and bears CE marking. Moisture exposure class according to ETAG 022: A.

Exclusively use system-approved adhesives for areas that require CE conformity or compliance with the German general certificate of national technical approval (abP). Please contact us at the address shown in this data sheet for further information about suitable adhesives and the corresponding test certificates.

Accordingly, DITRA-HEAT protects the substrate from damage resulting from permeating moisture and aggressive substances. Cover abutting joints with the sealing adhesive KERDI-COLL-L and full embed the sealing bands KERDI-KEBA (minimum width: 12.5 cm). To waterproof floor/wall transitions, adhere KERDI-KEBA to DITRA-HEAT in floor areas and directly to the substrate in wall areas, using the corresponding widths. The sealing bands should have at least 5 cm of coverage. Schlüter-KERDI-KEBA is also suitable for creating functional connections to fixed structural elements such as door or window elements made of metal, wood, or plastic. As a first step, apply Schlüter-KERDI-FIX to the corresponding areas of the structural elements. Then fully embed the remaining width fully over DITRA-HEAT, using the adhesive KERDI-COLL-L. The suitability of KERDI-FIX for the material of the structural elements must be verified in each case. Separate DITRA-HEAT above existing movement joints or structural joints and cover the abutting joints with Schlüter-KERDI-FLEX. Heating cables may not cross expansion joints or dummy joints. KERDI-FLEX is also recommended for flexible finishing edges. As an alternative, you can also use KERDI-KEBA with a corresponding loop.

Note regarding floor drains:
Schlüter-KERDI-DRAIN and Schlüter-KERDI-LINE are components that were specifically developed for connection to bonded waterproofing assemblies. Schlüter-DITRA-HEAT can be quickly and reliably connected in these cases with the use of KERDI-COLL-L.

Thermostat:
The system heating cables of DITRA-HEAT-E may only be operated with DITRA-HEAT-E thermostats.

Material

Schlüter®-DITRA-HEAT is a polypropylene membrane with a cut-back stud structure. A fleece fabric is laminated on the underside. The thickness of the membrane, including the stud structure, is approx. 5.5 mm or approx. 7.5 mm in the case of Schlüter®- DITRA-HEAT-DUO.

Polypropylene is not UV-stable in the long term; the product should not be stored in places with prolonged exposure to direct sunlight.

Material properties and areas of application:

Schlüter®-DITRA-HEAT is non-rotting, waterproof, elastic and crack-bridging. The material is highly resistant to solutions containing salts, acids and alkalis, as well as many organic solvents, alcohols and oils. The suitability of the material must be verified based on the specific chemical stresses, including the anticipated concentration, temperature and length of exposure. The water vapour diffusion seal of the material is relatively high. The material is physiologically safe. In special cases, the suitability of the material must be verified based on the anticipated chemical and mechanical stresses. The information provided below is intended as a general guideline.

Due to the special characteristics of the system, coverings installed over Schlüter®- DITRA-HEAT may have a certain hollow sound when they are walked upon with hard shoes or tapped with a hard object.

The use of Schlüter®-DITRA-HEAT in conjunction with heating cables for floor/wall heating is only approved for interior areas.

Note

The adhesive and the covering materials used in conjunction with DITRA-HEAT must be suitable for the corresponding application and meet the applicable requirements.

If installing covering materials that are sensitive to moisture (e.g. natural stone or synthetic resin panels) or in the case of moisture underneath the covering (e.g. from green screeds), it is recommended to trowel the sealing adhesive Schlüter-KERDI-COLL-L over the joints of DITRA-HEAT and to cover the joints with the 12.5 cm wide sealing band Schlüter-KERDI-KEBA. The use of fast-setting thin-bed adhesive may be an advantage for specific projects. It is recommended to lay out timber boards over pathways, e.g. for material transport, to protect DITRA-HEAT.

Notes regarding movement joints:

The installation membrane DITRA-HEAT must be separated above existing movement joints. Heating cables may not be installed over movement joints. In accordance with the applicable construction standards, movement joints must be continued in the tile covering. Coverings made of large format tiles over DITRA-HEAT must be divided into fields with movement joints in accordance with the applicable regulations.

We recommend the use of our Schlüter-DILEX profiles. Depending on the anticipated movements, profiles such as Schlüter-DILEX-BT or Schlüter-DILEX-KSBT should be installed over structural movement joints.

The buildup of tensions must be addressed at the edge of coverings, for example at upright construction elements or floor-wall-transitions. The edge joints and connection joints must meet the applicable professional regulations. Their dimensions must be sufficient to rule out the build-up of tensions. We recommend the use of our various profile types of the Schlüter-DILEX series.

Technical data

Heating cable

• Nominal voltage 230 Volt
• Rating
  • 136 W/m² (spacing: every third stud ≙ 9 cm)
  • 200 W/m² (spacing: every second stud ≙ 6 cm)
• Cold connection line 1 x 4,00 m
• Minimum installation temperature 5 °C
• Smallest bending radius 6 x dA
• Resistance tolerance -5 % / +10 % at 20 °C
• VDE tested IEC 60800 Class M1
• Cold-warm transition Seamless, without shrink technology
• Insulation Fluoroplastic
• Fuse model IPX7

Schlüter®-DITRA-HEAT-E-R / -R-WIFI*:
Thermostat for floor and wall coverings with features such as

• Self-explanatory colour touchscreen display 5.1 cm (2")
• Selectable room settings
• Mechanical main switch
• Second remote sensor provided as a spare sensor
• Backlit display
• Pre-set and adjustable timer programs
• Energy consumption display
• Adjustable user language
• Compatible with European integrated switch clusters (5.5 x 5.5 cm).
• 16 A switching capacity = with 230 V: 3680 W
• Display removal tool included in the scope of supply
• Colour similar to RAL 9003

* Wi-Fi function for integration into a wireless system for remote control via the “Schlüter-HEAT-Control” app

Schlüter®-DITRA-HEAT-E-R3:
Feature thermostat for floor and wall coverings with features such as

• Self-explanatory colour touchscreen display 8.9 cm (3.5")
• Selectable room settings
• Mechanical main switch
• Second remote sensor provided as a spare sensor
• Backlit display
• Pre-set and adjustable timer programs
• Energy consumption display
• Adjustable user language
• 16 A switching capacity = with 230 V: 3680 W
• Colour similar to RAL 9003

Schlüter®-DITRA-HEAT-E-R4:
Analogue thermostat for heating floor and wall coverings with features such as

• Mechanical on/off switch
• Input for control via external timer
• Second remote sensor provided as a spare sensor
• Integration into conventional switch programs
• Suitable for integration into conventional 5 x 5 cm switch programs (built-in adapter is required for switch series 5.5 x 5.5 cm)
• 16 A switching capacity = with 230 V: 3680 W
• Colour similar to RAL 9010

Schlüter®-DITRA-HEAT-E-ZS
Thermostat installation set

• Conduit for sensor wire (2.5 m)
• Aluminum sensor sleeve
• Plastic junction box

Sets for floor and wall surfaces

Schlüter®-DITRA-HEAT-E-S contains:

• Touchscreen thermostat Schlüter-DITRA-HEAT-E-R * or Smart thermostat Schlüter-DITRA-HEAT-E-R-WIFI. Both include two remote sensors.
• Heating cable Schlüter-DITRA-HEAT-E-HK for the area to be heated (installed around every 3rd stud ≙ 136 W/m2)
• Uncoupling mats Schlüter-DITRA-HEAT-MA
• 2 junction boxes
• 1 x conduit (3 m)

Wall installation sets

Schlüter®-DITRA-HEAT-E-WS contains:

• Touchscreen thermostat Schlüter-DITRA-HEAT-E-R * or Smart thermostat Schlüter-DITRA-HEAT-E-R-WIFI. Both include two remote sensors.
• Heating cable Schlüter-DITRA-HEAT-E-HK for the area to be heated (installed around every 2nd stud ≙ 200 W/m2)
• Uncoupling mats Schlüter-DITRA-HEAT-MA
• 2 junction boxes
• 1 x conduit (3 m)

Sets for wall and floor Areas with thermal barrier

Schlüter®-DITRA-HEAT-E-DUO-S contains:

• Touchscreen thermostat Schlüter-DITRA-HEAT-E-R * or Smart thermostat Schlüter-DITRA-HEAT-E-R-WIFI. Both include two remote sensors.
• Heating cable Schlüter-DITRA-HEAT-E-HK for the area to be heated (installed around every 3rd stud ≙ 136 W/m2)
• Uncoupling mats Schlüter-DITRA-HEAT-DUO-MA
• 2 junction boxes
• 1 x conduit (3 m)

Sets for wall areas with thermal barrier

Schlüter®-DITRA-HEAT-E-DUO-WS contains:

• Touchscreen thermostat Schlüter-DITRA-HEAT-E-R * or Smart thermostat Schlüter-DITRA-HEAT-E-R-WIFI. Both include two remote sensors
• Heating cable Schlüter-DITRA-HEAT-E-HK for the area to be heated
• (installed around every 2nd stud ≙ 200 W/m2)
• Uncoupling mats Schlüter-DITRA-HEAT-DUO-MA
• 2 junction boxes
• 1 x conduit (3 m)

Products / Sets

• Schlüter®-DITRA-HEAT
• Schlüter®-DITRA-HEAT-DUO
• Schlüter®-DITRA-HEAT-E-R
• Schlüter®-DITRA-HEAT-E-CT
• Schlüter®-DITRA-HEAT-E-HK
• Complete sets Schlüter®-DITRA-HEAT-E

Substrates for Schlüter®-DITRA-HEAT:

Always check the substrates on which DITRA-HEAT is to be installed 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 DITRA-HEAT. To guarantee the effective heating of the floor, thermal insulation must be included in all installations directly above the ground or over unheated rooms. For a faster heat-up response, we recommend the installation of DITRA-HEAT-DUO with its thermal break property over unheated screed assemblies or the use of Schlüter-KERDI-BOARD as an insulation layer (see data sheet 12.1).

Concrete

Concrete is subject to long-term form changes due to curing processes. Additional tensions may result from the deflection of concrete and pre-stressed concrete. Schlüter-DITRA-HEAT uncouples the tensions between the concrete and the tile covering, which means that tiles can be installed as soon as the concrete reaches a sufficient level of stability.

Cementitious screeds

In accordance with the applicable regulations, cementitious screeds must be at least 28 days old and have a residual moisture level below 2 CM% before tiles can be installed. However, floating screeds and heated screeds are particularly prone to curling and cracking, for example because of weight loads and temperature fluctuations. With DITRA-HEAT, tiles can be installed on green cementitious screeds as soon as they are ready to bear weight.

Cracks and buckles forming in the screed at a later time will be neutralised by DITRA-HEAT and will not be transferred to the tile covering.

Gypsum screeds

According to the applicable rules, just testing gypsum screeds may only have a residual moisture level of max. 0.5 CM% when the tiles are installed. When DITRA-HEAT is used, the tile covering is ready to be installed as soon as the residual moisture level drops below 2 CM%. If necessary, treat the screed surface as recommended by professional standards and manufacturer instructions (sanding, priming). Schlüter-DITRA-HEAT can be installed with suitable thin-bed tile adhesive. Schlüter-DITRA-HEAT protects the screed against permeating moisture at the surface. Gypsum screeds are sensitive to moisture, making it necessary to protect the screed from further moisture, e.g., high humidity.

Heated screeds

Schlüter-DITRA-HEAT may also be installed over heated screeds, with the above material notes to be observed (cement, gypsum). When DITRA-HEAT is used, the covering assembly may be heated up 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.

Note:
The use of DITRA-HEAT over heated screeds allows for individual, partial warming that is separate from the central heating system. That allows for completely switching off the central heating system during seasonal transition periods. Schlüter-DITRA-HEAT can also help cover peak loads. Due to the thermal separation property of Schlüter-DITRA-HEAT-DUO, it is not recommended for use on heated screeds.

Synthetic coverings and coatings

All surfaces must be weight-bearing and be suitable or pre-treated to enable the bonding of a suitable adhesive with the anchoring fleece of DITRA-HEAT. The suitability of the adhesive for the substrate and for DITRA-HEAT 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. In principle, panels can be used as a substrate on walls and floors in interior areas. The thickness of the panels should be selected to ensure sufficient impact resistance in conjunction with a suitable support structure. The panels must be sufficiently secured with closely spaced screw connections. All joints must either feature tongue-and-groove connections or be covered with adhesive. Edge joints of approx. 10 mm must be kept open at the connections with adjoining construction parts. Schlüter-DITRA-HEAT neutralises the stresses in the tile covering and also prevents the permeation of moisture.

Wooden floors

The direct installation of ceramic coverings over wooden 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 prior to the installation of DITRA-HEAT. Experts recommend the installation of an additional layer of plywood. Uneven floors must be levelled before the installation of other materials.

Masonry/mixed substrates

Solid masonry made of bricks, lime sand bricks, cement-bonded stones, cellular concrete or the like is generally a suitable substrate for DITRA-HEAT. Uneven sections must be levelled in advance. In case of restoration projects as well as renovations and extensions, substrates frequently consist of mixed materials (mixed masonry), which are prone to cracking at the edges due to varying deformation. The installation of DITRA-HEAT ensures that the resulting stresses and cracks are not transferred to the tile covering.

Plaster/ gypsum

Gypsum-based substrates should be completely dry in accordance with testing that follows the recognized regulations – surfaces may need to be pre-treated with a primer. Schlüter-DITRA-HEAT can be installed with dry-set mortars or other suitable thin-set mortars.

Video

Enjoy our videos showing the product itself as well as possible areas of application.