Repairing foundations and footings of an existing building or structure is called underpinning. This process involves extending the foundation depth or spreading the structure weight across a greater surface area.

There are various methods of underpinning that can help a house, building or facility that is suffering from subsidence.

Most traditional methods of underpinning involve excavation and concrete.  This technique comprises digging large holes beneath a building, mechanically supporting it and then pouring the concrete mixture into the voids that are located. This can be a very invasive, time consuming, expensive and an incredibly messy process.

Offering a fast, clean and non-invasive method, Mainmark uses a resin injection process called Teretek. Often described as ‘key hole surgery’ for properties, this allows the team to strengthen building foundations in an environmentally-friendly way.

Which method is best for you?

To choose the most suitable underpinning method for your building or structure, it is essential to fully understand what problems the foundations are currently experiencing or could create if not fixed.

There are a whole host of reasons why underpinning may need to occur:

  • The soil structure under the foundations may have changed in condition
  • Soil features were not properly considered during the design and construction phases
  • The original foundation ground is no longer strong enough to support the structure
  • Ground works of neighbouring structures could endanger the foundations of your structure
  • The construction of additional floors and extensions

Foundation subsidence problems are created by weak ground that cannot support the weight of structures or floors above it. This is when they start to subside and cause major building hazards.

There are many different reasons for weak ground, both natural and man-made. Loosely packed soils or sand, or even human activities such as excavating and drilling techniques, can cause issues.

What is subsidence?

Subsidence is the gradual downward movement or sinking of an area of land and it causes buildings to sink or become uneven because of the weak supporting ground.

There are many different causes of subsidence, including extreme weather conditions that cause the moisture content in the soil to contract or expand, nearby excavations that cause the ground to vibrate, poorly compacted soil during the construction of the building and incomplete or inadequate foundations or footings.

Subsidence can happen over large areas of a foundation or just a small specific area. It can progress over a lengthy period, or literally overnight if the structure has to contend with major movement or vibrations from nearby activities or natural hazardous events.

When supporting ground has been affected by subsidence, the foundations may no longer be adequately supported, resulting in unexpected structural damage, such as sinking floors and cracks in the building’s walls which can all have a serious impact on the operations and safety of the building.

How Mainmark can help fix the problem?

If you think your business could have weak foundations which need structural repairs or underpinning, you should contact Mainmark to help assess the problems and give advice on possible repairs.

Mainmark are ground engineering specialists with more than 20 years’ international experience in working on subsidence problems.

Over the years we have developed unique underpinning techniques likened to keyhole surgery using our proprietary resin injection solution known as Teretek®.

This method involves an engineered resin solution being injected into foundation ground under structures, through very small holes or penetrations. The resin flows into the voids, compressing the soil and placing pressure on the ground, thus raising and re-levelling the above ground structure. It is a fast, reliable and cost-effective alternative to traditional concrete underpinning.

It addresses subsidence and the resulting problems such as sinking and cracked floors, cracked walls, or doors and windows that won’t close properly.

The benefits of Teretek® compared to traditional underpinning

Cost effective – no hidden fees or extra costs

Non-invasive – our process involves keyhole surgery, hence no major excavations

Resident friendly – work is carried out with minimal disruption, in most cases you won’t even need to move out!

Time efficient – on average we can get your home back to level in little as a day or within 1 – 2 weeks depending on the technologies we utilise

Worry-free – our resin product comes backed by a 20-year product warranty for added peace of mind

Accurate – using state of the art technology our qualified technicians can re-level extremely accurately

Reputable – our specialised methods have been mastered for over 25 years with thousands of satisfied customers

Problems we solve

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Holes and Voids

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