Frequently Asked Questions

For the use of our Alveplac® stabilizing plate, you do not need to purchase a geotextile as it is directly integrated into the product through an injection welding process. This ensures that the gravel stays in place and prevents the growth of weeds brought by birds.

Stone, concrete and ceramic tile paving are all options for riser pedestal terraces. Ultimately, the choice will depend on the intended use, laying pattern and, of course, the desired visual appearance of your paved terrace.

It is perfectly possible to install these pedestals on well-prepared uneven ground. They work equally well on existing concrete slabs, and can be installed immediately adjacent to existing installations with no problem.

These wedges are used directly beneath joists or any other joinery components requiring height adjustment. There are a number of rules governing their positioning:

• Provide clearance of at least 10 mm where joists are laid parallel to the direction of water flow; 20 mm where joists are laid at right angles to the direction of water flow.
• Leave the recommended spacing of 70 cm between wedges (depending on joist cross-section and type of timber).
• Space joists at 50 cm centres when using natural timber decking boards, and at 40 cm centres when using composite boards (check with the manufacturer).

Wedges can be screwed, glued or nailed in place to ensure optimum fixing.

Ideal for laying create tiled, ceramic or paved terraces, the Cleman® self-levelling 80/130 pedestal can be used to correct gradients of up to 5% on uneven ground. Its height adjustability provides greater flexibility for adapting terrace structures to project site constraints and the height of terrace required.

The Cleman® adjustable 40/55 paving pedestal is used to create tiled, ceramic or paved terraces for pedestrian use. It offers 3 adjustment options: pre-setting using the driver bit, manual setting using the screw adjuster, and final adjustment using the special adjustment wrench, all of which enables an extremely precise level of height adjustment. It offers not only fast and structurally stable installation, but also optimised side cladding facilitated by the 2 supports integrated into the base flange. This pedestal is compatible with self-supporting paving compliant with French classification T7, T11, or F+. It is not suitable for use with the paved side finishing plate.

Once the deck boards have been laid in accordance with French building regulation DTU 51.4., Profildeck® screws are screwed directly through the decking board and into the aluminium joist, using a maximum torque rating of 7 Nm (position “18” on a 20-position 18V cordless combi drill). It is important to check that the screws are compatible with the material used, particularly in the case of composite decking boards, which may require specific fixing methods.

The Jouplast® Elevo decking pedestal for metal posts can be installed on all types of ground, including slopes and loose or uneven ground. It is ideal for sites where traditional preparation (excavation, concrete slab casting etc.) is not feasible, and enables quick and stable construction.

3mm stabilising spacers are inserted between paving slabs as they are laid. They can also be used in combination as intersection spacers, depending on the configuration of your installation. Once installation is complete, the spacers can be removed for a sleek final finish.

The Cleman® and Easio® pedestal height extender adds 60 mm to the initial pedestal height. By stacking up to 4 height extenders, the initial height can be increased by total of 240 mm.

Simple and fast to install, MODULESCA® 20 cm steps require only two tools: a screwdriver and a spirit level. Having first prepared the ground, simply position the first step in the desired location, screw it in place and fill the module with aggregate or concrete. Each subsequent step is then easily assembled using the notch and slider system and the screws supplied to lock the modules securely together. For curving steps, the maximum angle of rotation for a 20 cm module is 10°.

ouplast® breakable flat shims are designed for low-height adjustments.

Available in various thicknesses (2, 3, and 5 mm), they are ideal for leveling carpentry elements, compensating for irregularities, and ensuring proper spacing between materials.

Their divisible design offers great flexibility and adapts to the specific requirements of each project. They provide excellent stability and high compressive strength.

All our slabs can withstand weights that are perfectly reasonable for traffic:

• Alveplac® and Greenplac® can withstand up to 600T/m² filled with gravel or grass.
• Urbangravel® can withstand up to 800T/m² filled with gravel.
• The entire URBANIT® range, designed for more intensive vehicle traffic, can withstand up to 1000T/m² filled with grass, gravel or paving stones.

The mechanical strength of our slabs is the fundamental criterion in our development process in order to guarantee soil stability.

Our self-levelling pedestals can be installed on uneven ground, as long as the ground has been properly prepared. They also work on existing concrete slabs, and it is very convenient to be able to install them against an existing structure without any difficulty.

Low-profile pedestals can only be used on flat, level floors with no difference in level exceeding 1.5%. In addition, pedestals can only be installed on stabilised ground or existing concrete slabs.

Is your floor uneven? Don’t panic, you can fix this by following a few simple floor preparation steps. For more information, please refer to our installation advice documents.

Our paver or timber decking pedestals come with a 10-year guarantee, based on our terms and conditions of sale and our installation guidelines. Furthermore, we have never been aware of any deterioration in the pedestals over time.

On another note, when walking on a raised patio, you may feel a slight sliding or clicking sensation. To remedy this, we strongly recommend using our isolation pad, to be placed on the paving slabs, as well as our rubber cushions, to be placed on each pedestal head. These two products, made from recycled tyres, cushion movement on the patio and reduce noise and resonance.

To find out more, please take a look at our products: the isolation pad and the rubber cushion.

Before laying the slabs or wooden boards, it is important to ensure that your pedestals are securely fixed in place. Here are the steps to follow to secure them, regardless of the type of pedestal chosen:

Start by marking out the area. This will determine the exact location and dimensions of your patio. Then, prepare the ground.

On bare ground

1. Clean the area and remove any vegetation or debris.
2. Remove approximately 15 cm of topsoil. For slightly sloping ground (up to 5%), self-levelling pedestals can compensate for this incline.
3. Lay a geotextile membrane: this prevents weeds from growing back and limits rising damp. Cut it to the dimensions of the area to be covered and ensure there is sufficient overlap at the edges.
4. Create a base layer using 0/31 crushed stone.
5. Compact the surface using a vibrating plate.

A small exception applies to the 8 x 20 mm terrace pedestal: we recommend creating a draining base layer made of 30/60 or 40/80 crushed stone instead of 0/31 crushed stone. Then, finish with a thin layer of gravel to achieve a perfectly level surface. Finally, compact it with a vibrating plate.

On a concrete slab

1. Remove any debris (rubble, stones, etc.) that could hinder the installation or prevent the pedestals from staying firmly in place.
2. Check the available heights at the thresholds. This will help you choose the correct size of pedestals for your project.

Depending on the nature of the ground, a drainage base can be laid beforehand using a layer of 30/60 or 40/80 aggregate.

If the resulting surface still has some imperfections, it is recommended to create a bedding layer using quarry sand or crushed sand of type 0/4. This will facilitate the installation of low-profile pedestals. It is recommended to use a vibrating plate between each layer.

On uneven or sloping ground, it is not necessary to level the surface if you are subsequently using self-levelling pedestals.

For the longevity of your outdoor arrangement, we recommend laying a sub-base or leveling sand bed with a grain size between 0 and 5, which you level with a screed. The thickness of the layer should be between 1 and 5 cm maximum. This foundation layer will ensure proper soil drainage and stability of the installation.

The surface on which the paved patio will be built must be prepared before work can begin. Unprepared ground (e.g. unprepared soil) may change over time and can be subject to movement. Depending on the weight it will subjected to and the local climate (dry periods, heavy rainfall, etc.). For these reasons, it is important to stabilise the ground beneath the patio to ensure long-term stability of your project.

Jouplast 5 mm flat packers are designed to meet minimal packing requirements across a broad range of joinery and construction projects. Their 5 mm thickness corrects any irregularities in the underlying structure and provides stable, durable packing. They also guarantee excellent ventilation of timber decking structures, in accordance with the recommendations of DTU 51.4. Very strong, they can support heavy loads with no deflection.