Groundworks by the Numbers: Diggers, Depths and Driveway Timings

Most of the cost and time in a new driveway or patio goes into work that nobody sees once the job is finished: digging out, building up a sub-base and getting the levels right. Charting a few of those numbers makes quotes easier to compare, and explains why two prices for what looks like the same drive can be so far apart.

Choosing a digger by weight

Mechanical excavation is far quicker than digging by hand, but the machine has to suit the site. Digger size is usually charted by operating weight:

• 1 tonne micro digger: gardens, tight residential plots and side access, with tracks that close up to fit through narrow gaps
• 1.5 tonne micro digger: driveway dig-outs, landscaping and medium excavation
• 3 tonne mini digger: larger groundworks and commercial projects

Hiring the machine with an experienced operator usually works out better than self-drive, because the job gets done safely and to the right depth first time. For example, mini digger hire in Sheffield with a driver starts from around £250 a day for the smaller machines.

Depths worth charting

• Patios: a compacted sub-base, typically around 100mm or more, under the bedding layer and slabs
• Driveways: a deeper sub-base, typically 150mm or more, to carry the weight of a car
• Soft or clay ground: extra depth or a membrane, decided on site

These are general guides rather than fixed rules. A good installer checks the subsoil, the slope and where the rain will go before pricing, and those checks are the main reason quotes differ.

Resin by the numbers

Resin is one of the easiest surfaces to chart because its key figures are so clear. A well-laid resin bound drive is permeable, so rain drains straight through without extra drainage, and with a brush and an occasional jet wash it should last around 20 years. It is designed for cars and light vehicles rather than heavy loading.

Installers of resin bound driveways in Sheffield will usually lay resin bound rather than resin bonded on a drive, as bonded resin is not permeable and suits patios better.

Walls on the same timeline

A new driveway often means changing the entrance too: widening a gateway, rebuilding a front wall or replacing a hedge with brickwork. That work belongs on the chart before the surface goes down, so the wall and the drive line up. Experienced Sheffield bricklayers can build the wall, any retaining walls and the piers as part of the same project.

1. Survey and quote: ground, drainage and access checked
2. Excavation: digger and driver on site
3. Walls and kerbs: built on proper footings
4. Sub-base: laid and compacted in layers
5. Surface: resin, block paving, tarmac or stone

A handful of figures turns a driveway quote into something you can check line by line. For more on driveway companies and the numbers behind their work, see our driveway category.