Frequently Asked Questions

The spacing between the pedestals will depend on the type of wood and the cross-section of the joists you are using. As a general rule, we recommend a distance of 70 cm between each adjustable pedestal. For joists, we recommend a centre-to-centre distance of 50 cm if your decking is made of natural wood boards. Please note that these guidelines differ for a composite decking.

Yes, our self-levelling pedestals have an adjustable height to the nearest millimetre.

Our Essential pedestals have a height range of up to 485 mm when combined with risers. For the Cleman® range with dual adjustment, it is possible to adjust their height from 40 to 470 mm using a riser.

To ensure optimal stabilisation of your paving stones, the bedding (or sub-base) must meet the following minimum requirements:

• Allow for drainage of rainwater and runoff. Example: your soil can be considered well-drained if there is never any standing water after heavy rain. If this is not the case, it is recommended that you drain the surface either by installing drains in the ground or by creating a drainage layer with 40/80 crushed stone.
• Not be subject to rising groundwater. Example: your ground is subject to rising groundwater if, after a long period of rain, it becomes damp and unstable.
• Have sufficient load-bearing capacity for the intended use (pedestrian or vehicle traffic). Example: a site can be considered stabilised when it has been driven on for several years. In the case of a new house, it is advisable to check the condition of the ground with the earthworks company.
• Have no unevenness greater than 1 cm over 3 m.

If in doubt, it is best to check with an earthworks company.

Installation on slopes up to 10% is possible. The installation must be carried out against a concrete kerb at the bottom.

Before installing our stabilisation slab for paving stones, it is important and mandatory to prepare the ground according to the intended use.

For a pedestrian walkway :

1. Dig out 10 cm of soil.
2. Compact the surface using a lawn roller to optimise the levelling of the ground. If there are any large stones remaining, remove them by hand.
3. Unroll a 120g/m² geotextile. For perfect coverage, overlap the geotextile strips by 10 cm.

For a driveway :

1. Dig out the soil to a depth of 20 to 30 cm.
2. Compact using a vibrating plate to ensure the ground is level.
3. Unroll a first 120g/m² geotextile. For perfect coverage, overlap the geotextile strips by 10 cm.
4. Create a 10 to 20 cm foundation layer consisting of a mixture of 70% 30/60 gravel and 30% sand.
5. Compact using a vibrating plate.
6. Roll out another 120g/m² geotextile.

Our block paving stabilisers can be used with all 15x15x6 cm high concrete block pavers. Stone and sandstone paving can also be used, although their higher cost makes them less common.

Jouplast 2mm flat packers are thin packers designed specifically for use where minimal packing is required. Their snappable design means they can be used in one-piece or snapped into 2 or 4 sections to provide 4 packers in 1. They also ensure excellent ventilation for timber decking structures, and comply fully with the minimum spacing requirement set by the French DTU 51.4 technical standard (3 mm between joist and decking board). Ultra-strong, they can support heavy loads with no deflection (crush resistance in excess of 2 tonnes).

The Jouplast® square gripper/isolation mat is an accessory designed to be applied to a paved side finishing plate. It damps any acoustic resonances and improves paving adhesion. It offers greater terrace stability and comfort.

The number of pedestals required depends on the total area to be covered and the format of the paving used:

• For a 20 m² paved terrace using 60 x 60 cm paving slabs: approximately 80 pedestals (4 pedestals per m²).
• For a 40 m² paved terrace using 80 x 80 cm paving slabs: approximately 280 pedestals (7 pedestals/m²).

The recommendations of the paving manufacturer must be followed in order to calculate the precise number of paving pedestals required.

Cleman® 28/40 pedestals can be installed only on stabilised ground or a precast concrete slab. They are not suitable for use on loose soil or unprepared ground and must be laid on a flat surface whose gradient must not exceed 1.5%.

Jouplast® ridged wedges are designed to wedge and level timber structures constructed indoors and outdoors. Their saw-tooth ridging system facilitates precise spacing and ensures maximum stability of joists, floors and other joinery. Available in two formats (90 mm and 170 mm), they provide adjustment from 11 to 40 mm, depending on the combination used. Compatible with flat packers, they are ultra-strong (crush resistance over 2 tonnes) and have moulded holes for easy fixing with no drilling needed.

Our solutions are adapted to all types of structure, including balconies, patios and sloping ground. Be careful to choose the right type of self-leveling riser pedestal for the gradient.

The paved side finishing plate support kit extender increases the height of the paving side cladding support by 20 mm. It is used to adjust the height beneath paving when installing terraces or other structures to ensure a flat finish and sufficient stability.

The Cleman® adjustment wrench can be used with straight or offset patterns of square and rectangular paving slabs, with the exception of 2/3 – 1/3 patterns. However, it cannot be used to adjust the height of the riser pedestals located under the longer sides of rectangular paving slabs, or with paving slabs thicker than 30 mm.

For an exotic wood deck, several species stand out for their durability, resistance to moisture, and aesthetics. Here are some of the best options:

• Ipé: Native to South America, Ipé is very dense and resistant. It is naturally rot-resistant and offers excellent durability against the elements.
• Cumaru: Also known as “Brazilian teak,” Cumaru is a hard wood with a beautiful color ranging from reddish-brown to yellow-brown. It is very stable and resistant.
• Teak: Known for its resistance to water and insects, teak is often used for decks and outdoor furniture. It has a beautiful golden color that can be maintained with regular care.
• Padauk: This African wood is very dense and durable, with a color ranging from red to pinkish-brown. It is also very stable and stain-resistant.

It is possible to build a straight staircase or a quarter-turn staircase.

For a straight staircase:

• Minimum ground slope: 24.7° or 46%
• Minimum tread depth: 235 mm
• Maximum ground slope: 36° or 70%
• Maximum tread depth: 370 mm

For a curved quarter-turn staircase:

• Rotation axis: Center of the step
• Minimum inner radius: 570 mm
• Minimum outer radius: 1,530 mm
• Maximum step rotation angle: 13°

Note: The curved staircase can be assembled independently on either the right or left side using the module.

Jouplast® decking joist pedestals have a crush test resistance of over 1 tonne. However, the weight that a raised decking can support depends not only on the strength of the pedestals and whether they have a high load resistance, but also on the type of wood used for the decking. We therefore advise you to consult your timber supplier for more precise information on this matter.

More generally, if you are planning to place a heavy item on your raised decking, such as a hot tub for example, we recommend our PROFILDECK® solution (aluminium joists), which will allow for better weight distribution across the subframe structure of the installation.

Fixego® must be used for wooden decking projects that comply with French DTU 51.4 standards. It is fixed directly to wooden joists using screws.

Once installed, it holds the boards in place, creating regular spacing between them and promoting air circulation and water drainage.

We recommend using wooden joists made from the same type of wood as the decking boards. We do not recommend using Fixego® with wood that is knotty or unstable, such as acacia.

We do not advise using Fixego® on joists less than 45 mm wide.

Yes, our finishing profiles, side finishing plates and support kit are compatible with sloping or uneven ground.

In fact, it is not our finishing accessories that adapt to the slope, but the pedestal. By adjusting the pedestal’s range of adjustment, it is possible to compensate for a slope or uneven ground and thus complete the finish of your raised patio using our side finishing profiles, support kits and side finishing plates.

However, we strongly advise you to prepare your ground properly to ensure a flat, even surface without any unexpected issues caused by poorly managed slopes. For more details, watch our video on ground preparation.

There are several methods for concealing the joist pedestals on your raised decking.

If the clearance height allows it, you can create wooden side finishes for a uniform look.

For a finish at the end of the joist, simply place a lateral riser support on the base of the joist pedestal and snap off the tab. You can then more easily position and secure the joists. Do not forget to secure the vertical joist with a screw. You can finally attach the fascia board to the joist using 2 screws.

For a finish along the joist, you have two options:

1. Create a “ladder” edge structure. To do this, you will first need to place a lateral rising support at the base of each pedestal and snap off the tab. Then, position perpendicular reinforcements around the edge to allow pedestal movement. Place a small vertical joist of the measured height against each lateral riser support and fix the fascia board to the joist using 2 screws.
2. Add a peripheral joist. To do this, start by placing a lateral rising support at the base of each pedestal and snap off the tab. Then, position a small joist vertically against each lateral rising support and fix a spacer between the 2 peripheral joists to secure them together. Finally, simply fix the fascia board to the joist using 2 screws.

If your clearance height is too low, do not worry! We have alternatives to offer:

1. Decorative pebbles can be an elegant solution. Placing pebbles along the edge of your decking will create a natural and attractive look that blends harmoniously into your outdoor living space. The pebbles add an organic and warm touch, whilst elegantly concealing the unclad sections.
2. Another interesting finishing touch option for your raised decking is the use of small L-shaped corner pieces or finishing profiles. These 2×2 cm or 3×3 cm angles, depending on your needs, add a touch of structure and neatness to your deck. Easy to fix, L-shaped angles provide a stylish and durable finish to the edges of your elevated wooden deck.

To build a functional and safe outdoor staircase on a raised terrace, for example, you must comply with a few rules:

• Dimensions: maximum height 19 cm, minimum tread depth 24 cm and minimum width 90 cm.
• Slope: the slope must be between 25 and 45° to allow for comfortable and safe ascent and descent.

A 2 cm top layer of 5/15 or 8/16 driveable gravel should be added to ensure that all the cells are totally filled. Once the gravel has been poured into the stabilisation grid, it should no longer be possible to see the grid itself.