How level must the floor be for building a safe padel court?

The floor for a padel court must be level to within a maximum deviation of 3 millimetres, measured over a length of 3 metres. This is the standard norm for sports floors, where consistent ball bounce and safe movement go hand in hand. How strictly this requirement is enforced in practice and what the consequences of a deviation are, you can read in the questions below.

Which flatness tolerances apply to a padel court?

A padel court has a maximum flatness deviation of 3 mm over a measuring length of 3 metres. This norm stems from international sports floor standards and is also applied by inspection bodies such as Kiwa ISA Sport when assessing padel courts for official use. The flatter the subsurface, the more predictable the ball bounce and the safer the playing surface.

This tolerance sounds strict, and it is. A padel court is an intensively used playing field where players change direction quickly, play close to the walls and expect the ball to come back at a consistent height after a bounce. Even small irregularities can disturb that pattern. In addition, an uneven floor puts extra load on the steel structure, because the structure is not supported evenly.

The flatness norm applies to the final playing surface, so including the foundation layer and the artificial turf. The artificial turf itself does not compensate for irregularities in the subsurface. If the foundation is not level, neither is the end result.

What happens if the floor is not level enough?

A floor that does not meet the flatness tolerance of 3 mm per 3 metres causes problems on three levels: playing quality, safety and structural integrity. The ball bounce becomes irregular, which makes the game unpredictable. Players trip more easily over irregularities, which increases the risk of ankle injuries. And the steel structure no longer rests evenly on its foundation, which leads to extra stress in the connections.

In the longer term, an uneven subsurface can lead to subsidence in the artificial turf, loose connections in the cage structure and premature wear of materials. This is not a theoretical risk: in practice we regularly see that courts built on an insufficiently prepared subsurface show noticeable problems after just a few years.

For courts used for official matches, an inspection by Kiwa ISA Sport is also mandatory. A floor that does not meet the flatness norm will not pass that inspection. That means the court is not suitable for official use until the subsurface has been repaired.

Which foundation type produces the most level subsurface?

In practice, Supersub produces the most level subsurface of all common foundation types for padel courts. Supersub is a foundation solution based on foam concrete: a light, self-levelling material that automatically finds its own level during pouring. As a result, manual corrections after pouring are minimal and the end result is exceptionally level.

Drainage concrete is a good second option and is widely used for outdoor courts. It is a water-permeable type of concrete in which rainwater drains directly through the foundation into the ground. Drainage concrete also produces a level surface, but requires a little more attention during installation to meet the flatness norm. When correctly applied, however, the quality of drainage concrete is excellent and the foundation lasts 25 to 40 years on average.

ZOAB asphalt, a porous asphalt variant, is less common for padel courts but can be a good choice in specific situations. Its flatness depends on the workmanship and the underlying soil conditions. Which foundation type is most suitable always depends on the location, the soil conditions and the intended use. Good foundation advice therefore always starts with a soil probing (CPT) of the subsurface.

How is the flatness of a padel court floor measured?

The flatness of a padel court floor is measured with a straight edge 3 metres long, laid across the surface. The maximum deviation between the straight edge and the floor surface is measured at several points and in several directions. The maximum permitted deviation is 3 mm. This is a simple but reliable method that is widely used in construction practice.

On professional projects, the measurement is carried out at several locations spread across the entire playing area, both lengthwise and crosswise. This gives a complete picture of the flatness of the floor and ensures local irregularities are not missed. The measurement takes place on the finished foundation layer, before the artificial turf is laid.

After completion, flatness can also be assessed as part of an inspection by Kiwa ISA Sport. During that inspection, the entire playing surface is assessed on, among other things, flatness, shock absorption and ball bounce. Only courts that meet all norms receive a certificate for official use.

Can an existing floor be used as the subsurface for a padel court?

An existing floor can be used as the subsurface for a padel court, but only if that floor meets the flatness norm of 3 mm per 3 metres and has sufficient load-bearing capacity. For an indoor padel court in an existing sports hall, this is sometimes feasible. At outdoor locations, such as an existing tennis court, reusing the sub-base is also possible in certain cases and can save costs.

Before an existing floor is approved as a subsurface, an inspection must always take place. This looks at the current flatness, any cracks or subsidence, the load-bearing capacity of the subsurface and, at outdoor locations, the water drainage. If the existing floor does not comply at one or more points, repair work is needed. In some cases it is cheaper and more durable to build a new foundation than to repair an existing one.

When converting a tennis court to a padel court, the dimensions and layout of the subsurface change. A tennis court is larger than a padel court, which means the foundation has to be partly rebuilt or adapted. Whether and to what extent the existing sub-base can be reused is always a decision specific to the location.

Who is responsible for the correct flatness with turnkey construction?

With turnkey construction of a padel court the full responsibility for the correct flatness lies with the contractor carrying out the complete package. That means: from groundwork and foundation through to the handover of the playing surface. The client does not need any technical knowledge of flatness norms or foundation types. The contractor guarantees the end result.

This is an important advantage of a turnkey approach compared to working with several separate parties. If the foundation is built by party A and the artificial turf by party B, a grey area quickly arises over who is responsible if the flatness of the final surface does not comply. With a turnkey contract that discussion does not arise: one party, one responsibility.

Do you want to know for certain what the flatness requirements mean for your specific location? Then also take a look at the information on the cost of an indoor padel court, so you get a complete picture of what a well-built project involves.

How I-Padel helps with a level and safe subsurface

We handle the entire process from groundwork to handover, including the foundation. That means we are responsible for the flatness of the subsurface and of the final surface. No discussion about who did what: we stand behind the whole.

What we do in concrete terms:

• Before every project, we carry out a site check, including an assessment of the soil conditions.
• On that basis, we advise on the most suitable foundation type: drainage concrete, Supersub or ZOAB asphalt.
• The foundation is built to the flatness norm of 3 mm per 3 metres.
• We produce the steel structure entirely in-house, which means we can also tailor the structure to the specific subsurface and location.
• At handover, the court meets all requirements for inspection by Kiwa ISA Sport.

Whether it concerns a new indoor court, an outdoor location or the conversion of an existing tennis court: we are happy to think along with you, without obligation. Get in touch for an initial exploration of your project.

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