My House Is Cracking After a Drought: What Should I Do?

Understanding the Causes of Drought-Related Cracks

Clay Soil Shrinkage

The main cause of post-drought cracking is differential shrinkage of clay soil. When the ground lacks water, clay particles contract and shrink. This uneven movement causes the foundations to settle unevenly, creating stress within the structure and producing cracks.

At-Risk Areas

Certain regions are particularly vulnerable, including:

• The Mediterranean region and south-west France
• Areas with clay or silty soils
• Homes built on unstable ground

Warning Signs

Cracks can show up in different ways:

• Stair-step cracks in brickwork or masonry
• Diagonal cracks on facade walls
• Doors and windows that stick or no longer close properly
• Cracks at expansion joints

Assessing the Severity of Cracks

Minor Cracks (< 2mm)

These surface cracks are generally cosmetic and can result from normal thermal movement or mortar shrinkage. Simple filling is usually enough.

Moderate Cracks (2-5mm)

These cracks require closer attention, as they may indicate structural movement. It’s recommended to:

• Measure their progression regularly
• Consult a building expert
• Clean and seal the cracks

Severe Cracks (> 5mm)

Cracks over 5mm signal a structural issue. It is essential to consult an expert or structural engineer. These cracks may require:

• A full structural assessment
• Consolidation work
• An insurance claim for the damage

Solutions and Repairs

Filling Small Cracks

For cracks under 2mm:

1. Clean the crack with a brush or compressed air
2. Lightly dampen the surface
3. Apply a filling mortar or facade render
4. Smooth and let dry
5. Repaint if needed

Filling Moderate Cracks

For cracks between 2 and 5mm:

• Slightly widen the crack in a V-shape to improve adhesion
• Use a quality acrylic or polyurethane sealant
• Fill the crack progressively
• Apply a flexible sealant to allow for movement

Structural Repairs

For severe cracks:

• Resin injection: a professional technique for sealing structural cracks
• Structural reinforcement: adding steel ties or reinforcements
• Soil treatment: resin injection to stabilise the ground
• Drainage installation: to manage soil moisture

Preventive Measures and Maintenance

Managing Soil Moisture

• Water the ground regularly around the house during dry periods
• Install surface drains to carry away rainwater
• Avoid extreme moisture swings near the foundations

Foundation Care

• Install a perimeter drainage system
• Create a protective zone around the house (regular mulching)
• Check pipework for potential leaks

Regular Monitoring

• Inspect your house regularly, especially after dry periods
• Take photos to track how cracks evolve
• Note dates and weather conditions

When to Call in an Expert

It’s advisable to bring in a professional in the following cases:

• Cracks over 2mm
• Cracks widening quickly
• Doors and windows out of alignment
• Several cracks appearing at once
• Visible settling or apparent instability

The expert will carry out:

• A full visual inspection
• A study of the ground and foundations
• Precise recommendations for repair
• An expert report (useful for insurance purposes)

Administrative Steps and Insurance

Natural Disaster Declaration

Drought-related cracks may be covered under the « natural disaster » clause of your home insurance. You should:

1. File a claim promptly (usually within 10 days)
2. Have the damage assessed by an insurance expert
3. Provide evidence and photos of the damage

Contacting Your Local Council

Check with your local council regarding:

• The natural disaster declaration for your area
• Available regional assistance
• Repair support schemes

Practical Advice

Do

• ✓ Document the state of the cracks regularly
• ✓ Keep the soil around the house well maintained
• ✓ Seek advice quickly if in doubt
• ✓ Check your insurance coverage

Don’t

• ✗ Ignore cracks even if they seem minor
• ✗ Carry out major repairs yourself without an expert assessment
• ✗ Let the situation worsen before acting
• ✗ Forget to notify your insurer

Conclusion

Drought-related cracking is an issue affecting many homes across France. While some cracks are superficial and easy to repair, it’s important to assess them correctly and take the right action. Early detection, proactive moisture management and expert consultation when in doubt are key to protecting your property. Don’t hesitate to reach out to building professionals and your insurer for the support you need.