Structural Underpinning London
Faster more efficient alternatives to traditional underpinning in London
There are an array of building that may require structural underpinning in London From the historically
to the modern commercial buildings, both have one thing in common, and that is that traditional underpinning
methods are unsuitable. The busyness and congestion in London make traditional methods of underpinning
impractical and in many cases infeasible. The fragility of the historically significant buildings of London
make older methods of underpinning dangerous to the integrity of the structure. The disruption caused by
excavation and heavy machinery means that business and property owners in London often suffer significant loss
SAU offers a solution to underpinning that removes all of the hassle and disruption typically found with
traditional underpinning, whilst providing a superior outcome. This makes SAU the best solution for
underpinning work on domestic, commercial and historically significant buildings in London.
What is Underpinning?
Underpinning is a method of ground strengthening which involves the excavation and expansion of the
foundations which support the load. Underpinning work is a major task which requires the use of heavy
machinery and excavation. For properties in busy areas of London, ground strengthening can cause major
disruption, however, SAU are able to apply a modern, non-invasive approach to underpinning that minimises
disruption, and takes a fraction of the time.
For properties in London, underpinning may need to be carried out due to the following issues:
• Inadequate planning which fails to correctly identify the soil characteristics during the
• A change in the soil conditions under the foundation
• The original foundation is no longer adequate due to ageing
• Repair work/excavation in a nearby area has endangered the current foundations
• Additional floors are being constructed underground
The issues listed above are not exclusive to properties in London, and SAU offer nationwide solutions to
underpinning projects. However, the geography of London means that many of the issues listed above are often
exacerbated by the array of historic architecture, as well as the large population and the busy road and rail
networks. These factors often put strain on London’s infrastructure and can lead to foundational issues in
buildings across the city.
Older Types of Underpinning VS Resin Injection
The most important factor that needs to be considered when any structural work is carried out is safety. It is
imperative that any structural work done is carried out by experts and that the underpinning work done leaves
the building in a safe and supported way. For business and property owners in London, convenience is also key
when any structural work is done. Older methods of underpinning are not convenient as they often require
excavation and the use of heavy machinery. Some of the older methods of underpinning include:
Mass Concrete Underpinning – The process of replacing the soil under foundations followed by
concrete pouring. Typically used at shallow depths, box-shaped parts replace the soil in a pre-determined
Pilled Underpinning – A method of underpinning typically used at more substantial depths. During
the underpinning process, steel cased piles that can be filled with concrete are installed. The piled
foundations can be divided into three categories depending on the installation method, these are; driven
piles, drilled piles and jacked piles.
Jet Grounding – A high velocity jet of cement grout is used in the creation of geometry of
grouted soil. Jet grouting is typically used to create columns of grouted soil underneath an existing
foundation. This method is effective across a variety of soil types. Jet grouting is also an effective method
of underpinning as there is no need for load transfer structures. However, because jet grouting requires
drilling and the use high-pressure, it is not always suitable for very sensitive foundations due to the soil
These traditional underpinning methods are fast becoming a last resort for property owners in London. The use
of resin injection is a far superior method, which does not require excavation, as well as taking a fraction
of the time of traditional methods. There is also no need for occupants to leave the property whilst work is
carried out. All of these factors are extremely important for business and property owners in London to
consider when deciding which method of underpinning they will choose.
Resin Injection Solutions – Is a much faster and efficient method of
underpinning used for soil
stabilisation and the re-levelling of floors. Injections of resin materials made up of multi-component,
expanding materials replace the need for heavily pressurised, hydraulic systems. By providing a much less
disruptive and safer alternative to other methods of underpinning, resin injection shortens the completion
time of work to a matter of days, without the need for any excavation.