Installing floating terrace pavers

Lay your terrace pavers without mortar: the Schlüter-TROBA system solutions give your pavers a secure hold and ensure reliable drainage.

Terrace with unbonded pavers and lounge furniture

Attractive terrace surfaces with open joints

No mortar, no adhesive, no joint sealant: where terrace pavers are installed floating or without bonding, they rest on a crushed stone layer or another suitable support base such as stilt supports or mortar rings. The type of installation has many advantages, depending on the design – and goes hand-in-hand with our Schlüter-TROBA system solutions.

Partially covered terrace with large-format paving and pool © Schlueter-Systems

The system solutions of the Schlüter-TROBA series offer innovative products for all who are involved in professional surfacing in gardens and landscaping.

Partially covered terrace with large-format paving and pool © Schlueter-Systems

Components of the TROBA-LEVEL series can be combined in various ways and can level slopes of up to 10% with millimetre prevision.

Edge strips in light grey terrace pavers between a house and an adjacent border © Schlueter-Systems

The system for an optimal edge solution: unbonded pavers have been combined with the TROBA-LINE-TLK-E gravel retaining angle on this border.

What is unbonded installation?

Unbonded or floating installation has no fixed bond between the surface pavers and the substructure. Instead, the pavers are placed either unbonded or resting on a suitable substrate, either by only their corners or over their whole surface, depending on the design. This installation method is highly suitable where outdoor ceramic or natural stone is desired on terraces, roof terraces or balconies. The result is a cover with open joints that can be lifted again at any time. Surface water flows down through the joints to the waterproofing level and from there is guided away via a sloped surface drainage system. A decisive factor for waterproofing and drainage is that the substrate is prepared professionally.

Three potential construction structures are available for installing a floating cover, depending on the substrate situation:

Installation on crushed stone

Terrace pavers laid on crushed stone

In this structure the pavers lie directly on a layer of bulking material with a slope of 2%.

Installation on mortar rings

Three terrace pavers laid with their corners on a mortar ring © Schlueter-Systems

In this construction, mortar or formwork rings are positioned at the joint intersections and in some cases at the centre of each paver.

Installation on paver supports

Terrace pavers laid on stilt supports © Schlueter-Systems

In this version the pavers rest on height-adjustable supports made of a long-life special plastic.

The advantages of unbonded installation

Simple to install
Little or no drying time
Cover can be removed again at any time
Excellent water permeability
Constant ventilation below covering
High frost resistance

Installation on crushed stone

With unbonded installation on crushed stone, the pavers are laid directly on a bedding layer of fine grit. The substructure generally consists of a base course built with sufficient slope and waterproofing. The base course must be capable of drainage and sufficiently deep to protect the cover from frost damage.

This method of installation is comparatively simple and low-cost and is often used in terraces and road or path construction for private dwellings. Since the pavers rest on the grid bed without a fixed bond to the substrate, this method is particularly suitable for heavy cover materials such as natural stone, whose heavy dead weight provide the necessary stability. To secure the cover against horizontal creep, the use of tile and paver spacers such as the Schlüter-TROBA-ZFK is additionally recommended.

Terrace pavers on a bed of crushed stone with a paver spacer to maintain spacing © Schlueter-Systems

If a balcony or roof terrace is covered in this way, the support structure must be protected against water penetration by a DIN 18531-compliant structural waterproofing. In such cases, Schlüter-TROBA is laid as a protective and separated layer between the waterproofing and the bedding layer. This protects the waterproofing from mechanical damage while also ensuring that seepage water is quickly and reliably drained away so that no 'ice concrete' can form.

Design example: unbonded installation on Schlüter-TROBA

On the concrete cantilever plate (1) a sloped screed (1a) is added with a slope of 1.5-2% for drainage.

A structural waterproofing element compliant with DIN 18531 is placed over the sloped screed.

To protect the waterproofing and to ensure effective removal of seepage water, the Schlüter-TROBA drainage sheet is placed between the waterproofing and the bedding layer.

On top of the drainage sheet, the bedding layer of crushed stone is added – the edges of which should be bonded.

To facilitate drainage when adjoining door elements at a low height, the Schlüter-TROBA-LINE drainage channel is used.

Along with the drainage channel, the Schlüter-TROBA-LINE-TLK-E gravel retaining angle is also fitted and combined with edge insulating strips at the rear.

A capping strip covers the edge of the wall where it meets the waterproofing.

The self-supporting terrace pavers are laid on the bedding layer and tapped into place. To maintain a consistent joint width and to prevent horizontal creepage, we recommend the use of the Schlüter-TROBA-ZFK tile and paver spacers.

The Schlüter-BARA-RKLT makes a suitable finishing profile for unbonded paver coverings. Its angled edge profile is made in colour-coated aluminium and features drainage openings.

Attached to the T-shaped profile chamber of the Schlüter-BARA-RKLT is the Schlüter-BARIN gutter system, which, combined with the drainage holes, ensures reliable drainage of seepage water.

Our products for installation in a crushed stone bed

Schlüter-TROBA drainage mat under a crushed stone bed


This long-lasting surface drainage sheet is laid between the waterproofing and the crushed stone and provides dome-like drainage channels that allow any seepage water to be reliably drained away.

Terrace pavers laid on crushed stone with a paver spacer to maintain consistent spacing


These stackable tile and paver spacers are positioned between the pavers during the paving process and ensure a consistent joint width of 3 mm.

Installation on mortar rings

In this method of installation, large-format, self-supporting pavers are attached at the joint intersections – and, if loading is high, also at the centre of each paver – with mortar.

For low structures formwork rings such as the Schlüter-TROBA-STELZ-DR serve as installation aids; these are placed at the joint intersections and filled with thin-bed mortar. The mortar should protrude a little beyond the rim to ensure that the paver element can be tapped into the correct height position. Alternatively, the formwork rings can be used simply as mould templates for the thin-bed mortar and re-used once the mortar has set.

A formwork ring on a drainage mat is filled with mortar and placed so that it supports the corners of the pavers © Schlueter-Systems
Three terrace pavers positioned with their corners over a mortar ring filled with mortar © Schlueter-Systems

For structures with more height, mortar rings such as the Schlüter-TROBA-STELZ-MR can be filled with fresh mortar to act as stilts for the paver covering. Single-grain mortar is most suitable here. The rings should be filled until the mortar protrudes about 5 mm above the rim, so that the pavers can be tapped into the correct height. The 25-mm high plastic rings can be stacked inside each other in a telescopic manner in order to achieve the required height adjustment of the covering, regardless of the slope of the substrate.

The finished covering drains through the open joints of the paver elements into the drainage level beneath. Any water accumulating at this level is then channelled by the slope inclination to the drainage system. Surface drainage systems such as Schlüter-TROBA-PLUS or TROBA-PLUS-G draw away the seepage water and also provide an air cushion that acts as thermal and sound insulation and protects the waterproofing beneath.

Our products for installation with mortar rings

Three terrace pavers laid with their corners on a mortar ring


These practical installation aids for large-format paver elements are placed on the drainage mat at the joint intersections of the pavers and filled with fresh mortar.

Terrace pavers fixed with thin-bed mortar elements over a surface drain


The 2 mm high formwork rings are positioned on top of the Schlüter-TROBA-PLUS-G drainage mat and filled with thin-bed mortar. They can either be left there as expended formwork or can be taken out and re-used once the mortar is set.

Cross-section of a construction with surface drainage, screed and decoupling membrane


Quick to install, ready for heavy loading: the surface drain supports the covering across its whole area while drawing off seepage water in the direction of the slope.

Terrace pavers on stilt supports resting on a TROBA-PLUS-G surface drain with mesh fabric


With filter fabric instead of filter fleece: this surface drain drains even faster and has been specially developed for covering assemblies that require an increased water drainage capacity.

Installation on paver supports

In this type of installation the pavers rest on height-adjustable, stackable supports. The construction systems normally comprise a number of combinable elements. Even the pre-assembled components of Schlüter-TROBA-LEVEL can be variably combined and allow construction heights from 3 mm to more than 1 m. Thus almost any incline situation, from 0% to 10%, can be reliably compensated – an unbeatable advantage where a spirit level-optimised substrate is not available. All elements can be stacked or rotated to the required height without special tools. 

The finished covering provides drainage through the open joints onto the waterproofing level of the terrace with its inbuilt slope. This form of installation is also designed to provide a constant ventilation beneath the covering, one benefit of which is to prevent frost damage. Highly sustainable: if a repair is necessary or if the area is remodelled, the pavers can be lifted easily and the system components re-used at any time.

Eight good reasons for Schlüter-TROBA-LEVEL

Straightforward product range

© Schlueter-Systems

With its seven combinable, height-adjustable or stackable components, Schlüter-TROBA-LEVEL is capable of reliably covering practically all slope and site situations. This facilitates not only handling and planning, but also saves both precious time and storage space.

Optimum drainage and constant ventilation

© Schlueter-Systems

The unbonded installation with open joints of 3 mm ensures rapid drainage of surface water for the further drainage of the underlying drainage bed. The constant ventilation helps prevent frost damage, and if necessary the components beneath the pavers can be accessed quickly.

Compensating for varying paver thicknesses

© Schlueter-Systems

The installation of different materials such as ceramic tile and natural stone frequently involves height discrepancies in the substrate and different material thicknesses that must be offset. Thanks to its divisible paver supports and levelling shims, TROBA-LEVEL offers the optimal solution.

Can be cut for edges and corner formations

© Schlueter-Systems

TROBA-LEVEL is also ideally suited for use along edges and in corners: the elements can be easily cut to size for neat abutment. Grooves in the materials facilitate accurate sizing. This does not affect the functioning of the system based on snapping together and twisting.

No twisting, no coming unscrewed

© Schlueter-Systems

Rapid assembly: all TROBA-LEVEL elements are stacked or are rotated to the required height without special tools. A lock prevents rotatable parts from coming undone and falling out during height adjustment. At the same time, catches prevent unwanted dimension changes occurring due to vibration or weight loading.

High flexibility through combination

© Schlueter-Systems

Schlüter-TROBA-LEVEL is designed from the outset to be used in a wide variety of combinations – which simplifies your planning and ensures maximum flexibility during installation. The system allows you to respond with ease to unfamiliar or altered conditions at the site without the need for large storage capacity.

For all slope situations up to 10%

© Schlueter-Systems

Whether you wish to level out, reduce or install on a slope, the flexible TROBA-LEVEL combination options offer solutions for all slope situations up to 10%. TROBA-LEVEL relegates 'wobbling' due to sloping or uneven terrain or irregularities in the pavers to the past, since every single corner can be individually adjusted with millimetre precision.

Extra tough and reusable components

© Schlueter-Systems

All components are made from a special plastic that acts to deaden sound and is resistant to wind and weather and also to horizontal creep and weight loading. Moreover, the load distribution disks and protection mats prevent damage to the substrate. If the area is later remodelled, these long-life products can easily be removed and used again.

Our products for installation on paver supports

A light-brown terrace paver lying on a black TROBA-LEVEL-PL 10 paver support

Schlüter-TROBA-LEVEL-PL 10

Our cuttable paver supports can be stacked to a height of up to 200 mm and feature elastic crosspieces that absorb movements and ensure a homogenous joint pattern.

A beige terrace paver lying on a black TROBA-LEVEL-PLA 30 height adapter


Reach greater construction heights faster: one or more height adapters can be placed between two paver supports and stacked up to a height of 300 mm. They can also be combined with TROBA-LEVEL-PLV 60 and TROBA-LEVEL-LV 3.

Terrace construction with grey pavers on TROBA-LEVEL-PLV 60 paver supports of different heights


Pre-assembled and rotatable: the paver supports can be adjusted continuously between 60 and 130 mm without special tools. Assembly heights up to 520 mm can be achieved by stacking multiple TROBA-LEVEL-PLV 60 units.

Schlüter-TROBA-LEVEL-LV 3 on a gravel bed under a terrace paver


Larger diameter, wider load distribution – these paver supports protect the substrate and make ideal supports for particularly low construction heights.

A Schlüter-TROBA-LEVEL-PLS 6 pad in rubber granulate on a dark sand bed with a TROBA-LEVEL-PLV 60 inserted


These protective pads in rubber granulate are always used to protect the waterproofing assembly if no other full-area protection is installed.

A single black Schlüter-TROBA-LEVEL-PLA 70 height adapter


When you need to build high: this height adapter can easily be attached to the bottom plate of TROBA-LEVEL-PLV 60 with screws. The thread features a protection mechanism against accidental loosening and a vibration lock.

A single black Schlüter-TROBA-LEVEL-AP 1 levelling platelet


Fine adjustment made easy: these levelling shims are an indispensable aid where the substrate is uneven or there are varying paver thicknesses or a slight slope. They extend up to 10 mm out per paver corner.

Cross-section of a construction with surface drainage, screed and decoupling membrane


Quick to install, ready for heavy loading: the surface drain supports the covering across its whole area while drawing off seepage water in the direction of the slope.

Terrace pavers on stilt supports resting on a TROBA-PLUS-G surface drain with mesh fabric


With filter fabric instead of filter fleece: this surface drain drains even faster and has been specially developed for covering assemblies that require an increased water drainage capacity.

Combination products for Schlüter-TROBA

Schlüter-TROBA-PLUS-G drainage mat on a terrace with grey pavers and TROBA-LEVEL supports

Surface drainage

With the TROBA, TROBA-PLUS and TROBA-PLUS-G drainage mats you can achieve capillary surface drainage, effective across its entire area, between the waterproofing and the covering assembly above.

A Schlüter-TROBA-LINE drainage channel between terrace tiles and the terrace door

Drainage channels

Our Schlüter-TROBA-LINE drainage channels drain accumulating water from your balcony or terrace surface to the waterproofing level with ease while also providing a low-barrier design with lower assembly heights.

Cross-section of a balcony structure with a Schlüter-BARA-RAK-EG finishing profile for the edging

Finishing edge

Our various Schlüter-BARA balcony edge profiles provide a clean finishing to the edge areas of balconies and terraces and also protect them reliably from the effects of weather.