If done correctly, renovation can be a much quicker way to provide new homes compared to new builds. Starting with the foundations and ensuring they are sound is the first step to preserving a building’s longevity and will allow for safe and reliable refurbishments to take place. If this is not addressed first, upgrading expensive interior fixtures like doors and windows can become an issue, should the property subside. This is time-consuming and expensive to fix, and the interiors may need to be re-replaced once again.
When assessing the foundations in an existing structure, understanding the soil type is critical. In the UK the most common soil types are clay, sand and silt, fill and organic:
Reactive clay soil swells when wet and shrinks when dry causing subsidence in drier conditions, or heave in wetter areas.
Sand and Silt
Structures on sand and silt soils often experience settlement caused by flowing groundwater, a natural underground watercourse or a leaking sewer or stormwater pipe.
Fill is earthen material placed and compacted in a hole or depression. Structures built on fill are susceptible to the same issues as those on sand and silt, especially when water washes away finer material. Settlement is worse if the fill is poorly compacted.
Organic soils, especially peat, are weak and highly compressible making them prone to settlement, as the weight of any structure above causes compaction. Primary settlement decreases over time but can total 100s of millimetres, resulting in significant structural issues.
If there is an issue with the foundations of a building that needs to be remediated, the modern method of resin injection will provide a less invasive alternative to traditional underpinning methods. This method allows both ground strengthening and re-levelling the structure, increasing the likelihood of it staying as intended and serving its purpose for the future.
The race to provide new homes and meet targets continues. With careful consideration given to the underlying ground of any building new or old, builders and developers can work confidently in the knowledge that their project has a head start.