Why Does Artificial Grass Sink? Causes, Fixes and Prevention

Artificial grass sinking is usually caused by movement beneath the surface rather than a fault with the grass itself. A settled sub-base, soft ground or drainage issues can create a physical hollow, while flattened fibres or displaced infill may only make the lawn look uneven. 

This guide explains how to tell the difference, identify the likely cause, decide whether a local repair is suitable and know when it's best to contact Tuda Grass or your original installer. 

Has the Artificial Grass Actually Sunk?

Before planning a repair, check whether the lawn has physically sunk or whether flattened fibres or uneven infill are creating the appearance of a dip.

Brush the grass against the pile direction, then walk across the area to see if it feels soft, hollow or lower than the surrounding lawn. Use a long straightedge to check for a physical dip, and inspect for standing water or movement around nearby joins and edges.

What Is the Difference Between Flattening and Sinking?

Flattening affects the grass fibres, while sinking changes the surface beneath. Both can occur together.

Could the Grass Still Be Settling?

New fibres may need brushing after installation, although a growing hollow is not part of normal settling. See our guide on how long artificial grass takes to settle if your lawn is newly installed.

What Causes Artificial Grass to Sink?

Artificial grass normally sinks because the supporting layers beneath it have lost stability. Ground movement, settlement and drainage issues are far more likely to be responsible than the grass product itself.

Possible causes include:

The position and shape of a dip can provide useful clues, although they should never be treated as proof of one specific cause.

How Can Poor Ground Preparation Lead to Sinking?

A weak or uneven foundation can allow sections of artificial grass to settle over time. Soft soil, disturbed ground or organic material beneath the base may continue to compress, creating visible dips.

Can Artificial Grass Be Laid Directly on Soil?

Untreated soil can move and soften, leaving the lawn without stable support. Follow verified Tuda Grass installation guidance for the most suitable base system.

Can Weak Edging Cause a Dip?

Yes. If edge restraint fails, supporting material may gradually shift, causing the perimeter of the lawn to become uneven.

How Do Drainage Problems Affect Artificial Grass?

Poor drainage can soften the supporting ground or allow fine material beneath the lawn to move, contributing to settlement. Existing dips may also collect water, making the problem more noticeable. Check whether water remains after rain, if the area feels softer when wet or whether water is flowing onto the lawn from nearby paving. 

Artificial grass allows water to pass through the backing, although it cannot resolve drainage problems beneath the surface. For more information on building a suitable drainage system, read our guide on what to lay under artificial grass for drainage. 

Can Heavy Furniture or Foot Traffic Create Dips?

Heavy furniture and repeated use can flatten fibres, compress infill and concentrate pressure in one area. A genuine dip is more likely where the supporting base was already weak or has started to settle.

If furniture leaves visible impressions, move it and brush the grass before assuming the base has sunk. If the surface remains physically lower, investigate further rather than relying on a cosmetic fix.

Can Sand Infill Fix a Furniture Impression?

Redistributing approved infill may help support flattened fibres. It should not be used to fill a structural hollow beneath the grass.

How Do You Fix Sunken Artificial Grass?

The right repair depends on whether the issue affects the fibres, infill or supporting base. Cosmetic problems may only need brushing, while a genuine hollow usually requires the grass to be lifted so the base can be repaired. 

Before starting, confirm the dip is structural, inspect the surrounding drainage and check how the grass has been installed. Avoid cutting the grass or filling the hollow from above. If you're unsure, contact Tuda Grass before attempting a repair.

How Can Small Dips and Uneven Areas Be Repaired?

A small isolated dip may be repaired if the surrounding base is stable and the grass can be lifted without damaging the backing or joins. The support beneath the affected area can then be rebuilt before the grass is refitted.

Can You Fill a Dip Without Lifting the Grass?

No. Surface infill may improve appearance, although it will not repair a structural hollow beneath the lawn.

Can the Same Artificial Grass Be Reused?

Possibly. If the backing and joins remain undamaged, the existing grass may be reused. Older bonded installations can be harder to lift, and replacement sections may not match exactly.

When Does the Base Need to Be Reinstalled?

A larger rebuild may be required where movement affects multiple areas or continues after previous repairs.

Signs suggesting a wider issue include:

Repeatedly repairing the lowest visible point will not resolve a broader problem if the supporting ground continues to move.

Should You Contact the Original Installer?

Yes, particularly if the installation is recent.

Before making contact, gather:

• Installation date.

• Product name.

• Photographs from several angles.

• A straightedge photograph showing the dip.

• Approximate dimensions.

• Notes explaining when the issue first appeared.

• Details of recent weather or changes in use.

Keeping this information together allows the installer or Tuda Grass to assess the situation more effectively.

How Can You Prevent Artificial Grass From Sinking?

Preventing settlement starts with a stable foundation. Remove unstable ground, investigate disturbed areas, provide suitable drainage and ensure the base is properly supported before the grass is laid. Following our guide on how to install artificial grass can help you understand the preparation needed for a long-lasting installation. After installation, inspect new dips early, keep drainage routes clear and monitor areas beneath permanent furniture or play equipment. 

Why Do the Right Base Materials Matter?

The supporting layers need to provide stability while allowing water to drain effectively. The most suitable system depends on the ground conditions and intended use.

Does Maintenance Prevent Sinking?

Routine brushing and debris removal help maintain appearance and highlight developing issues early. They cannot correct movement beneath the supporting base.

When Should You Ask a Professional for Help?

Professional assessment is recommended where the cause remains unclear, the dip affects a joined or bonded section, water repeatedly pools after rain or movement continues to spread.

Seek advice if:

• the hollow continues growing

• several areas are affected

• the lawn feels soft beneath foot

• joins begin separating

• the dip sits beside a drain or inspection cover

• mechanical compaction may be required

• a matching replacement section is needed

When you contact Tuda Grass, include photographs, approximate measurements, installation details, the product name where available and information about nearby joins, edges or drainage features.

Frequently Asked Questions About Sinking Artificial Grass

Is It Normal for New Artificial Grass to Sink?

Flattened fibres may recover after brushing, but a growing physical hollow is not part of normal settling.

Can You Add Sand to Level Sunken Artificial Grass?

No. Sand infill supports the pile but will not repair a structural dip beneath the surface.

Why Does My Artificial Grass Sink After Heavy Rain?

Rain can expose drainage issues or soft ground, making existing settlement more noticeable.

Can Garden Furniture Damage the Base?

Furniture mainly compresses fibres. A true dip usually indicates movement beneath the surface.

Can a Small Sunken Area Be Patched?

Possibly, provided the backing, joins and surrounding base remain suitable for repair.

Who Should Repair Sunken Artificial Grass?

For recent installations, contact the original installer first. Otherwise, use an experienced artificial grass installer familiar with base and join repairs.

Artificial grass can appear to sink for several reasons, and not every dip points to a failing base. Rule out flattened fibres and uneven infill before assuming the supporting layers have moved. If a physical hollow is present, investigate the underlying cause rather than covering the symptom. 

Local repairs may suit isolated areas, while widespread settlement usually needs professional assessment. If you're unsure, gather photographs and installation details before contacting Tuda Grass or your original installer.