Frequently Asked Questions

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.

While we can give an approximate number of pedestals per square metre based on the size of the chosen decking, it is impossible to calculate the number of aluminium joists for a deck without looking at each case individually.

However, for a private deck, we know that for a 55 mm high joist, the recommended centre-to-centre distance between pedestals is 80 cm. For a 27 mm high joist, the recommended centre-to-centre distance between pedestals is 50 cm. The centre-to-centre distance is the spacing between the joists.

For an accurate quote, you can submit your project to us and it will soon be possible to carry it out on our Jouplast® application.

It is necessary to prepare the surface on which the self-levelling adjustable terrace pedestals will be installed.

An unprepared ground (direct installation on soil or lawn, for example) may change over time and move depending on the weight it will bear and weather conditions (drought, heavy rain, etc.). This is why it is necessary to stabilise the ground to ensure the long-term durability of your project. Use is possible with wooden decking.

Jouplast® extra-flat terrace pedestals, such as the Essential Adjustable Pedestal 8 to 20 mm for slab terraces and the Essential Adjustable Pedestal 8 to 20 mm for joist installation, are specially designed for low-height terraces. They allow you to raise the terrace slightly without requiring major structural modifications.

Their innovative design makes them easy to install, saves time and guarantees optimal durability, while respecting the constraints of your project.

In addition to new constructions, these thin pedestals are ideal for renovating existing terraces, but also for landscaping small spaces and small terraces such as balconies and patios.

It is also possible to use these extra-flat pedestals around your swimming pool if the height of the recess is low.

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

Jouplast® 3 mm flat packers are designed specifically to meet minimal packing requirements. They also promote excellent ventilation for timber decking structures by creating a minimum gap of 3 mm between the decking board and the joist, as required by French technical standard DTU 51.4. Ultra-strong and with a crush resistance in excess of 2 tonnes, they are able to support heavy loads with no deflection.

The Essentiel® riser pedestal side cladding support is a quick, easy and ideal solution for applying the finishing touches to your terrace by creating a neat side finish. A 100% invisible solution that uses an innovative glue trap system to create a clean and attractive appearance. UV and frost-resistant, it is perfect for outdoor use. Its snappable tab enables fixing of all paving thicknesses and facilitates the installation of a vertical joists for timber decking.

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

• 4 riser pedestals per m² for a 20 m² terrace paved with 60 x 60 cm paving slabs, so 80 riser pedestals in all.
• 7 riser pedestals per m² for a 40 m² terrace paved with 80 x 80 cm paving slabs, so 280 riser pedestals in total.

These quantities may vary depending on the type of surface and the recommendations of the manufacturer.

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

• For a 20 m² terrace paved with 60 x 60 cm paving slabs, 4 riser pedestals per m², so 80 riser pedestals in all.
• For a 40 m² terrace paved with 80 x 80 cm paving slabs, 7 riser pedestals per m², so 280 riser pedestals in all.

This calculation may vary according to the type of paving used and recommendations of the manufacturer.

Profildeck® decking screws are specially designed to fix timber decking boards to Profildeck® system aluminium joists. Their self-tapping design ensures firm fixing with no need for pre-drilling. Manufactured from A4 stainless steel, they deliver excellent levels of weather and corrosion resistance.

Yes, Elevo riser pedestal is height-adjustable. It has an adjustment range of 95mm and a maximum height of 138mm. Where greater height is required, up to 4 Jouplast® 60 mm height extenders can be added.

The 3mm paving spacer is designed to create even spacing between paving slabs as they are laid to guarantee uniform spacing across the terrace and comply fully with all project constraints. Ideal when laying paving slabs, tiles and even timber decking boards.

Yes, Cleman® and Easio® 60mm riser pedestal height extenders can be stacked. Up to 4 height extenders can be stacked to achieve the required terrace height. You can therefore adjust riser pedestal heights to suit the needs of your project, without compromising the stability and strength of the overall installation. To ensure installation safety, the recommended maximum number of height extenders that can be stacked is 4.

The MODULESCA® connector kit is fully compatible with all MODULESCA® modules and steps. It can be used to connect two 20 cm modules together, connect a MODULESCA® step to a 20 cm module or or connect two MODULESCA® steps together.

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 use of a gravel stabiliser is essential to prevent ruts from forming, which can be seen when vehicles repeatedly drive past a garage, for example.

Our paving stone stabiliser is suitable for all concrete paving stones measuring 15 x 15 cm and 6 cm high. We also allow stone or sandstone paving stones, even though they are less common because they are more expensive.

We recommend choosing paving stones with smooth sides without protrusions. The paving stones must not be aged. Often when they are aged, they have been tapped and have irregularities. This makes them unique and attractive but uneven. Using this type of paving stone would make installation and traffic on our paving stone stabilisers unstable.

The manufacturing tolerance according to standard NF EN 1338 is +/-3mm on the 150 mm side.

This type of paving stone is easily found in DIY superstores or building material suppliers.

The durability of a terrace built on aluminium joists depends on several criteria.

• It is highly recommended that you prepare the ground properly so that the levelling of the terrain is stable, thereby guaranteeing the durability of the pedestal supports. We recommend that you watch our video on ground preparation to find out more.
• The choice of aluminium decking joists is itself a factor in the durability of the decking, as already mentioned in the section on the advantages of this installation system. The aluminium material makes the joists rot-proof and highly resistant to weathering and UV rays.
• The decking must be installed correctly on aluminium joists. To do this, we recommend that you read our installation advice. The joists must be fixed and aligned. Use our self-drilling screws, accessories from our range, to ensure the durability of your deck.
• Floor insulation: to prevent moisture rising, we recommend installing aluminium joists on wedges or pedestals. Jouplast® deck pedestals are the best choice for optimal adjustment.
• Use joist protection strips between the joists and decking boards to prevent water retention and extend the life of your aluminium joist decking.

Self-levelling pedestals for terraces are available from Jouplast for the slab and wood/composite range.

Yes, ground preparation is essential before installing extra-flat terrace pedestals. Proper ground preparation guarantees the durability of the terrace and prevents the pedestals from moving over time. However, this ground preparation does not require major work.

On a concrete slab, make sure to remove any contamination that could hinder the installation and stability of the pedestals.

On raw ground, some simple earthworks will be necessary. Start by excavating the ground to obtain a flat base and ensure proper levelling. The use of geotextile and the creation of a foundation layer of crushed gravel are then essential to accommodate the extra-flat adjustable pedestals in optimal conditions.

For installation on a waterproof surface, comply with the recommendations of DTU 43.1.