Riverside, Hollywater Road, Bordon, Hampshire, GU35 0AD
When it comes to groundworks, the soil type at your site in Petersfield or the neighbouring areas has a huge impact on the way we approach your project. As a result, we tailor our building footings, foundation installations and drainage preparation to suit the specific conditions we encounter. However, the excavation process holds a certain amount of unpredictability. As groundwork contractors, we have a good idea of what soil type lies beneath the surface based on decades of experience. There always remains the chance of a surprise, though. With our comprehensive knowledge of local soils, we operate flexibly to ensure the smoothest, most efficient service possible.
Below, we have provided a brief introduction to the most common types of soil our groundwork contractors encounter in the Petersfield area.
To discuss any aspect of groundworks in more detail, including building footings, foundation installations and drainage preparation, please call us on 01420 476 011 or 07796 476 011.
Rocks such as sandstone, solid chalk, limestone, granite and shale have high load-bearing capacities. In best case scenarios, our groundwork contractors only need to strip back and level-off the rock in order to produce a building platform. With impervious rocks, we install various drainage features for optimal water management.
We regularly utilise strip foundations as part of our groundworks. When working with chalk that isn’t too soft, we create strips 450mm wide for low-rise buildings. However, these foundations must be below the effects of frost action; usually at a depth of 700mm. When we encounter soft chalk, we simply dig to a depth where the material firms up.
Due to the way it shrinks and expands with varying moisture contents, the initial 900mm to 1,200mm of clay soils have a notable instability. As such, when faced with these soils in Petersfield, our groundworks team excavate to a minimum depth of 1m. If there are or were trees in the vicinity, this depth can reach 3m. At such depths, clay becomes much more stable.
This soil type provides an incredibly poor subsoil for groundworks of any kind. Be it drainage preparation, building footings or foundation installations, our groundwork contractors usually have to strip back the peat to find ground with load-bearing capabilities to a depth of 1.5m.
Sand and Gravel
With a compact and dry nature, sand and gravel, or a combination of both, provide subsoils that work well with strip foundation installations and building footings. When high water tables submerge these soils, however, the load-bearing capacity halves. In most cases, our groundwork contractors install such foundations as high as possible.
If sites in Petersfield have previously undergone excavation and subsequent backfilling, our groundwork contractors usually have to dig to a depth below the fill. This action ensures the best possible support for any groundworks, drainage preparation services and the system installations that follow.