Crack Formation and Repair
Implementation Team · Head of Operations 9 min read Updated: 16 October 2026
Contents
- Acrylic colour coats: Playing surface; resistant to UV and wear
- Filler (resurfacer) coat: Fills roughness and levels the surface
- Asphalt or concrete base: Most structural cracks start here
- Stabilised base: Spreads the load, drains water
- Compacted soil: If it settles, the upper layers crack too
Cracks in acrylic tennis courts can occur due to surface ageing, temperature fluctuations and movement of the sub-base. The correct repair method should be determined based on the depth of the crack—which is equal to its width—and the extent of movement.
How are hairline cracks repaired?
Dust, dirt and loose particles within the crack are removed. Once the area has dried, a crack-filling material compatible with the existing acrylic system is applied. The repair area is levelled to match the surrounding surface, and the necessary surface finish is completed. It should not be forgotten that even cracks that appear superficial may originate from the underlying structure.
How are deep and recurring cracks repaired?
In the case of active cracks, simply applying a filler may not be sufficient. The two-component Crack Repair System distributes the stress caused by ground movement over a wider area thanks to the flexible materials applied to the crack. The aim is to prevent the existing crack from appearing on the renewed playing surface.
This system does not eliminate the crack in the sub-base; nor does it prevent new cracks from forming in other areas of the court or the existing crack from extending beyond the repair area. In areas with subsidence or differences in ground level, sub-base repair may also be required.
To achieve a long-lasting result, the cause of the crack must first be identified, followed by the selection of a repair and surfacing system suitable for the ground. However, these cracks may re-form as the ground moves again.
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Clean the crack and the area around it
Use a wire brush and compressed air to remove dust, moss and loose particles from inside the crack. Any dust left inside is the number one reason why the filler fails to adhere.
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Wait for it to dry
If you have washed it, wait until the surface is completely dry. Filler applied to a damp crack may appear to set, but it will swell on the first hot day.
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Prepare and apply the filler
Mix the acrylic filler binder with silica sand in the ratio specified in the product instructions. Fill the crack by pressing the mixture in with a spatula; leave it slightly below the surface level.
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Second floor and levelling
Once the first coat has dried, it will settle slightly. Apply the second coat so that it is level with the surface, and work it into the edges using a wide trowel.
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Seal with a colour-filled finish
The repaired strip looks different from the surrounding area. Apply a thin coat of the court’s colour to it; spread it over a wide area to soften the edge.
Frequently asked questions
How long does a surface crack repair last?
A surface repair that has been properly cleaned and carried out at the right time of year will last as long as the rest of the court — that is, until the next general repainting. If it deteriorates prematurely, there is almost always one of two reasons: either the crack is actually structural, or dust or moisture has been left inside it.
When should you opt for replacement rather than repair?
A practical rule of thumb is this: if the patched and repaired areas account for more than ten per cent of the court, carrying out repairs simply becomes an expensive delay. If the surface is bulging in many places or water is pooling and not draining away in many areas, the problem lies not on the surface but beneath it; resurfacing is inevitable.
Can repairs be carried out during the winter months?
Acrylic products require warmth and low humidity to cure. If the ground temperature is below 10 °C or there is a risk of rain, the work should be postponed; otherwise, the repair, which appears to be complete, will flake off within the first season.
When will the court be ready for play after the repairs?
A minor surface repair can usually be opened for play within a day. If a colour coat has been applied, follow the curing time specified in the product instructions; footmarks will become permanent on a court that is opened for play too soon.