0800 873 835
New Zealand
Get a FREE quote
Welcome to Mainmark, your trusted underpinning, house re-levelling and subsidence experts in Christchurch.
As a leading ground engineering company with a strong local presence, we specialise in house re-levelling, subsidence repair, and more.
With 25 years of experience and a local team based right here in Christchurch, we deliver personalised solutions tailored to your unique needs.
Our expertise spans both residential and commercial properties, ensuring effective and long-lasting subsidence solutions for all types of structures.
Arrange your site assessment
Submit your enquiry using our online form. Include a brief message about the type of foundation issues you are experiencing. Our friendly customer service team will be in touch to schedule a site assessment that suits you.
"*" indicates required fields
Christchurch Underpinning, House Re-Levelling & Subsidence Experts
Homes in many parts of Christchurch may experience subsidence that leads to sunken foundations. Visible signs of this occurring at your property may include cracks forming in the exterior walls, a sliding door sticking and windows that become jammed.
Sloping and cracked floors, cracks in block walls, and doors and windows that won’t close properly can all be warning signs of foundation problems.
If a building becomes un-level due to subsidence, it can result in significant and expensive damage, particularly if left unaddressed. This is when homeowners may look to foundation repair companies for a solution to help ‘underpin’ their home.
Christchurch is often affected by seismic activity and challenging weather conditions
Many properties are built on soils that react to changes in moisture levels, with some clay foundation soils known to expand and contract following periods of heavy rain or drought.
Being located on an active fault line means properties are susceptible to liquefaction. Additionally, the region experiences extremes of dry conditions and heavy rains or localised flooding at different times of year.
However, properties in Christchurch and the surrounding region may face a wide range of factors that can lead to structural problems:
Leaking pipes
Over time, pipes under a property may deteriorate, become damaged or blocked, causing cracks which allow water to seep into the ground, both around and directly underneath the property. This is very common with clay pipes found in homes older than 20 years. Leaky gutters and downpipes or dripping outdoor taps are also frequently identified as the source of water collecting near house foundations.
Inadequate drainage
Moisture management is key for good foundation and footing maintenance. If the soil does not have adequate drainage, water will collect causing the ground to weaken and potentially cause the home to subside or ‘sink’.
Torrential rain
Christchurch is a low lying city, meaning some areas will be prone to flooding.
After heavy rainfall often comes flooding and sodden backyards that don’t have a chance to dry out due to ongoing cold and wet weather conditions. If clay soils become oversaturated, the ground loses its strength and footings settle through the clay. This is when house re-piling or house re-levelling is required.
Adjacent development
When building or renovation works take place at a neighbouring property, earthmoving and excavation can impact the stability of the soil on your side of the fence. This is even more problematic when coinciding with periods of heavy rain which soften the ground and may lead to soil erosion and voids. Equally, the clearing of trees associated with development can affect the water table as moisture is no longer drawn out of the soil by the tree’s roots.
Tree roots
If pipes start to develop cracks or have loose joints, tree roots will naturally grow towards these areas in search for water. Eventually, aggressive root systems will infiltrate pipes causing blockages which result in water spilling into the ground, impacting soil and the stability of house foundations.
Older constructions
With some homes in Christchurch dating back to the 1900s, it’s important to note that construction methods accepted at the time may contribute to foundation stability being compromised today. In some cases, a ring beam foundation will be smaller than is required by the current building code, which means changes in soil conditions over time, or the added weight of additions and renovations, may lead to structural movement.
The Mainmark solution
Since 1995 Mainmark has successfully raised and re-levelled thousands of homes and driveways throughout Christchurch
Mainmark offers some of the most advanced non-invasive resin injection technologies to quickly correct foundation ground issues with minimal mess or disruption.
With a sound knowledge of Christchurch’s unique local conditions, Mainmark utilises its Teretek® engineered resin injection solution to effectively raise, re-level, and re-support footings under a home. Teretek®is a unique two-in-one solution that provides both ground improvement and re-levels homes, backed by a 50-year product warranty. It increases ground bearing capacity, fills voids, rehabilitates foundation ground which helps raise sinking floors and reduces wall cracking, all at a fraction of the cost of traditional underpinning, and with no detrimental effects on the environment.
Benefits & Features
Mainmark’s Solutions & Technologies
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, with minimal disruption to the area.
A cost-effective alternative
Underpinning homes is generally a costly exercise using traditional methods due to the invasive nature of concrete underpinning, which is generally a lengthy and messy process. Teretek® is the modern way to raise, re-level and re-support your home by providing a unique two-in-one solution delivering both ground improvement and re-levelling.
It’s applied like keyhole surgery and most jobs can be done in a day, usually reducing the cost of the works when compared to traditional underpinning. As every home is different, Mainmark finds the best solution to treat the root of the problem. The cost of each job will vary according to:
- Your location
- The actual cause of the problem – what other things need to be resolved as part of the works eg. drainage
- The nature and condition of the foundation soil – including an assessment of the soil type
- The type and profile of the building footings – are the existing footings damaged or in need of replacement?
- The surroundings e.g. access to the site, adjacent buildings or retaining walls
- Unknown or unforeseeable underground conditions – problem solving on site
- The volume of material that will be required – an estimate will be provided but may need to be re-assessed following more detailed ground investigation
- The time that the work will take – based on Mainmark’s extensive experience.
