Your house may have subsidence if you notice cracks in walls, sinking or uneven floors, jammed doors, sticking windows, gaps around skirting boards or visible movement in concrete slabs. One sign alone may not confirm subsidence, but several symptoms appearing together can indicate foundation movement or weak ground beneath the home.

Subsidence can happen when the ground beneath a home sinks, shifts or loses strength. Common causes include weak soils, poor drainage, leaking pipes, erosion, poorly compacted ground, tree roots, heavy rain or seismic-related ground movement. When foundations lose support, parts of the house may settle unevenly.

In many cases, yes. Resin injection ground improvement may be used to fill voids, strengthen weak ground and help re-support affected foundations without major excavation. This can be a less disruptive alternative to traditional underpinning, depending on the cause of movement, site access and foundation conditions.

Subsidence repair focuses on treating the weak or moving ground beneath the home, while house re-levelling aims to lift affected areas back towards level. The two are often connected. If a home has sunk because of ground movement, the foundations may need to be re-supported before re-levelling can be completed.

Yes. Mainmark can assess homes affected by subsidence, sinking foundations or uneven floors and recommend a practical re-levelling or foundation repair solution. Depending on the site conditions, resin injection may be used to improve ground support and carefully lift affected areas back towards level.

The cost of subsidence repair depends on the size of the affected area, how much the home has moved, ground conditions, access and the repair method required. Because every property is different, a site assessment is the best way to understand the cause of movement and receive a tailored quote.

Subsidence refers to the ground beneath a home sinking or losing support. A sinking foundation is often the visible result of that movement. You may also notice cracked walls, sloping floors, jammed doors, sticking windows or gaps around the home. A professional assessment can confirm what is causing the issue.

If cracks are caused by subsidence or foundation movement, cosmetic repairs may not last until the underlying issue is addressed. Patching, painting or repairing plaster and brickwork first may lead to cracks returning. It is usually better to assess and repair the ground or foundation issue before completing cosmetic work.

Mainmark provides subsidence repair, foundation repair, underpinning and house re-levelling solutions for homeowners across New Zealand. If you are searching for help with a subsiding house, sinking foundation or uneven floors near you, Mainmark can inspect the issue and recommend a site-specific repair approach.

Mainmark is a specialist ground engineering company with New Zealand experience in subsidence repair, resin injection, underpinning and house re-levelling. Homeowners choose Mainmark for practical site assessments, non-invasive repair options and solutions focused on treating the cause of ground movement, not just the visible damage.