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A sign of subsidence
Foundation Repair – What does it look like when my house is out of level?
The appearance of internal or external wall cracks, inability to open and close windows and doors, cracked floors and more can all signal an unlevel building.
Once a building becomes unlevel, it is crucial to fix it immediately or risk further damage and potential hazards. This can require house re-levelling, cosmetic, foundation and footing repairs.
Using resin injection we can raise and re-level sunken buildings, while adding strength to the ground and support beneath your property.
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Re-levelling In Action
This remarkable solution is the key to raising, re-leveling, and re-supporting properties affected by subsidence. Our skilled team of engineers and technicians will guide you through the process, demonstrating how we restore structural integrity and eliminate those troublesome wall cracks.
Trust Mainmark for excellence for re-levelling
Sinking Foundations
Foundation Repair Caused by Sinking
Understanding subsidence causes and factors
The issue of subsidence, especially in the context of out-of-level homes, stems from a multitude of causes and contributing factors. All of these share a common thread—a shift in the ground, resulting in soil movement.
Moreover, the impact varies depending on the type of ground involved. When the ground undergoes changes, building subsidence becomes a prevalent concern.
In such cases, foundations or footings lose their full support and begin to sink due to the weakened ground.
Expansive Soils
A contributing factor to out-of-level homes is irregular soil behaviour. For example, soils containing reactive clay can expand or contract throughout the year. Rainy seasons will lead to soil expansion from moisture, while contraction occurs in the warm, dry conditions of hotter months.
These fluctuations could be regular, or the soil may expand and contract unevenly. This causes stress to the foundations of your home, which could lead to internal and/or external wall cracks. This will be of particular concern as more parts of the country experience extreme weather events year on year.
Tree Roots
Neighbouring trees and shrubs absorb water using their roots causing movement in the soil as it soaks up moisture in the ground.
Poor Drainage
One major contributor to out-of-level homes is issues with drainage. Pipes left unconnected, broken drains and other leakages can mean water drains into the soil under your home. This erodes the soil over time, leading to ground instability.
The soil under your home could also suffer from aeration, or voids could form. This eventually leads to ground instability, which causes wall cracks.
House Extensions
An out-of-level home can occur when the weight of your home increases beyond the foundation’s capacity. Wall extensions or other extra loads increase the weight of the house, as well as increasing the force exerted on the foundation and the soil it sits on.
As with soil expansion, uneven direction or distribution of this force can put stress on the structure. Wall cracks in this case might be the start of more serious issues.
Extreme or Seasonal Weather
Natural disasters such as flooding, drought and earthquakes affect soil moisture levels in particular clay resulting in excessive foundation movement.
Renovation or Construction
Vibration caused by nearby construction activity such as drilling or piling, or heavy road traffic causes soil particles to shift and settle, resulting in ground subsidence.
Expanding Materials
Expanding materials can also cause an out-of-level home. Some clay bricks expand as they age, increasing up to several millimetres per year in some cases. Concrete is another material that can contract or shift over time. These changes can cause wall cracks unless properly controlled.
Residential Subsidence Repair
Before & After Treatment
Houses that need to be re-levelled often develop cracks in walls, sinking floors, sticking windows or jammed doors.
Our innovative solutions are designed to address sinking foundations and cracked walls, ensuring long-lasting stability for your home. Whether it’s a sinking foundation or a cracked wall repair, sinking concrete floor or re-levelling a driveway, we provide tailored services to every job.
We offer a range of underpinning options, including resin injection underpinning and concrete underpinning, to help raise and relevel sunken structures. The cost of underpinning varies depending on factors like the extent of damage and the type of foundation. Our expert team specialises in underpinning footings and crack wall repair, ensuring your home is safe and secure for the future.
*Results may vary depending on site conditions, ground behaviour and specific requirements of each project.
Trust The Experts
Mainmark Specialises in Re-levelling Homes
If you’re worried, call Mainmark to assess your house. We can improve the ground beneath your house or carry out re-levelling to prevent further damage.
Mainmark specialises in re-levelling buildings that have experienced structural issues. We developed the Teretek and JOG technologies, which are versatile and suitable for re-levelling both simple and complex structures.
JOG is a non-invasive method of injecting cementitious grout beneath your house. This results in a supported and improved foundation.
Teretek uses a method of injecting polyurethane resin beneath your house. As the resin expands, it gently lifts the structure. This is also a non-invasive and cost-effective solution.
Why Choose Mainmark
The Leaders in Foundation Repair
50 Year Product Warranty
Backed by a 50-year warranty and ongoing support you can trust.
Benefits
Mainmark’s Level Correction Methods Are:
Fast
Our technologies have fast curing times and treated areas can be used immediately or without the delays compared to traditional repair methods.
Environmentally Inert
Our technologies use an inert material that is non-toxic and does not leach into the environment or affect the treated area.
Non-Invasive
Our solutions are of surgical nature compared to traditional methods.
Cost-Effective
Compared to traditional methods, our solutions are more cost-effective.
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Foundation Repair FAQs for New Zealand Homeowners
How do I know if my house needs foundation repair?
Your home may need foundation repair if you notice cracked walls, uneven or sloping floors, sinking floors, jammed doors, sticking windows, gaps around skirting boards or doors not closing properly. These signs can indicate foundation movement, settlement, weak ground or loss of support beneath the house.
What causes foundation problems in New Zealand homes?
Foundation problems can be caused by weak soils, poor drainage, leaking pipes, erosion, seasonal moisture changes, tree roots, seismic movement, house settlement or voids beneath foundations. When the ground beneath a home shifts or loses strength, foundations can move unevenly and cause visible damage throughout the property.
Can foundation movement cause cracks, uneven floors and sticking doors?
Yes. Foundation movement can cause wall cracks, cracks in brickwork, uneven floors, sinking slabs, jammed doors, sticking windows and gaps around frames or skirting boards. One symptom may have a simple cause, but several signs together can suggest the home needs a foundation assessment.
What is resin injection foundation repair?
Resin injection foundation repair involves injecting engineered expanding resin beneath affected foundations, slabs or footings. The resin expands into weak ground, fills voids, improves support and can help lift or re-level affected areas. It is often used as a non-invasive alternative to traditional underpinning, depending on site conditions.
Is resin injection an alternative to underpinning?
In many cases, yes. Resin injection can be a practical alternative to traditional underpinning because it uses small injection points rather than major excavation and concrete works. It may help stabilise sinking foundations, improve ground support and re-level affected areas with less disruption, depending on the cause and severity of movement.
Can Mainmark re-level a house with sinking foundations?
Yes. If a home has sinking foundations, foundation settlement or an unlevel structure, Mainmark can assess whether house re-levelling, foundation re-support or ground improvement is suitable. The aim is to treat the weak ground or loss of support beneath the home, not just repair the visible cracking or uneven floors.
How much does foundation repair cost in New Zealand?
Foundation repair cost depends on the size of the affected area, the amount of movement, ground conditions, access, foundation type and repair method required. Resin injection, underpinning, slab lifting and re-levelling can vary in cost. A site assessment is the best way to receive accurate advice and a tailored quote.
How long does foundation repair take?
Timing depends on the extent of foundation movement, access around the home and the repair method required. Non-invasive resin injection and re-levelling solutions can often be completed faster than traditional excavation-based repairs because they use targeted treatment and fast-curing materials. Mainmark can confirm timing after inspecting the property.
Who provides foundation repair near me in New Zealand?
Mainmark provides foundation repair, house foundation repair, foundation re-levelling, resin injection underpinning and ground improvement solutions for homeowners across New Zealand. If you are searching for a foundation repair specialist near you, Mainmark can assess the issue and recommend a practical, site-specific repair approach.
Why choose Mainmark for foundation repairs?
Mainmark is a specialist ground engineering company with New Zealand experience in foundation repair, foundation re-levelling, resin injection, underpinning alternatives and ground improvement. Homeowners choose Mainmark for practical site assessments, engineered repair methods, non-invasive solutions and a focus on treating the cause of movement, not just the visible symptoms.
Get a quote
Arrange a site assessment in 3 simple steps:
Step 1
Submit your enquiry using our online form. Include a brief message about the type of foundation issues you are experiencing.
Step 2
Our friendly customer service team will be in touch to schedule a site assessment that suits you.
Step 3
One of the Mainmark experts will visit your home or property, assess the damage, and ascertain the likely cause. They will establish the approach needed, creating a plan specific to the needs of your building and provide you with a detailed quote.
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Mainmark Ground Engineering (NZ) Ltd
