Re-levelling Repair – Houses and Building

House re-levelling is the process of correcting sections of a home that have sunk or settled unevenly. It may involve improving the ground beneath the foundations, restoring foundation support and carefully lifting the affected area towards the required level.

The appropriate method depends on the building, foundation type, ground conditions and extent of movement.

Your house may need re-levelling if you notice:

• Uneven or sloping floors
• Cracks in internal walls or ceilings
• Cracked exterior brickwork
• Doors or windows that stick
• Gaps around frames or skirting boards
• Sinking concrete floors or slabs
• One section of the house sitting lower than another
• Cracks that continue to widen or reappear

These signs can indicate house settlement or foundation movement, but a site assessment is needed to identify the cause.

Yes, many sinking houses can be re-levelled when the cause of the settlement and the condition of the foundations are properly understood.

Mainmark can use controlled ground engineering techniques to improve support beneath affected foundations and carefully raise settled areas. The amount of lift that can safely be achieved varies according to the building condition, foundation design and ground behaviour.

A house can sink when the soil beneath its foundations loses strength, changes volume or settles unevenly. Common causes include:

• Reactive clay soils shrinking or swelling
• Poorly compacted fill
• Leaking water or sewer pipes
• Inadequate stormwater drainage
• Erosion or soil washout
• Tree roots and changing soil moisture
• Voids beneath foundations
• Changes to surrounding ground conditions

Identifying the underlying cause is an important part of selecting the right house re-levelling solution.

Small injection points are created near the affected foundations. An engineered resin is then injected into the ground at carefully selected locations and depths.

As the resin expands, it can fill voids, improve the supporting ground and restore contact beneath the foundations. Where conditions allow, further controlled injection can gently raise the affected section of the house towards the required level.

House re-levelling describes the outcome of correcting a home that has settled unevenly. Underpinning is one method used to strengthen or restore support beneath its foundations.

Depending on the cause of movement, a house may be re-levelled using resin injection underpinning, traditional concrete underpinning, ground improvement or another engineered foundation repair method.

No. Restumping generally involves replacing or repairing the stumps that support a raised timber home. House re-levelling is a broader process that corrects uneven settlement and may be used for homes built on concrete slabs, strip footings, piers or other foundation systems.

A property assessment will determine whether the issue relates to deteriorated stumps, weak ground, foundation settlement or another cause.

House re-levelling costs vary considerably between properties. The final cost depends on factors such as:

• The size of the affected area
• How far the house has settled
• The depth and condition of the supporting soil
• The foundation type
• Site access
• The treatment method required
• Whether ground improvement or void filling is also needed

A site assessment is required before an accurate house re-levelling quote can be provided.

The timeframe depends on the size of the affected area, the amount of movement and the foundation repair method required.

Targeted resin injection treatments can often be completed more quickly than traditional excavation-based underpinning because the material is installed through small injection points. Larger or more complex residential re-levelling projects may require additional treatment stages.

Homeowners can often remain in their property during targeted resin injection works because the treatment generally requires limited excavation and relatively small equipment.

Access may need to be restricted around the treatment area while work is underway. Mainmark will explain any property-specific access or safety requirements before the project begins.

Yes. Where a concrete floor or slab has sunk because of settlement or a loss of ground support, slab re-levelling may be used to fill underlying voids, restore support and carefully lift the affected section.

The slab must first be assessed to determine the cause of movement and whether controlled lifting is appropriate.

Re-levelling may partially close some cracks as the affected section of the house is carefully raised, but this cannot be guaranteed. Results depend on the age, size and position of the cracks, the building materials and the amount of level correction achieved.

Remaining cracks, damaged plaster or separated brickwork may require separate cosmetic or structural repairs after the foundation treatment.

It is generally better to investigate the foundation movement before completing cosmetic crack repairs. Patching a crack will not correct sinking foundations, weak ground or a loss of support beneath the home.

Once the underlying movement has been assessed and treated, the remaining wall or ceiling damage can be repaired more effectively.

House re-levelling is intended to provide long-term foundation support, but the outcome depends on the cause of movement, ground conditions and any continuing external influences.

Issues such as leaking pipes, poor drainage, uncontrolled stormwater or significant changes in soil moisture may also need to be corrected. Mainmark assesses each property before recommending an appropriate foundation remediation plan.

You do not necessarily need to arrange a structural engineer before requesting an initial site assessment. Mainmark can inspect the property, review the visible signs of movement and identify the likely treatment requirements.

Additional engineering advice may be recommended where the movement is extensive, the building is structurally complex or formal engineering documentation is required.