We recently had the pleasure of working with a returning customer who needed foundations, oversite and blockwork for a new extension. With plans already drawn up, we carried out a site visit to assess the job in full. The original idea was a standard strip footing, but with our experience and the proximity to existing trees and hedgerows, we recommended a raft foundation instead. This method helps avoid future issues with the building inspector and ensures better long-term stability.

The next hurdle was access. The site had only an 800mm wide gate and a tight 800mm passage between a hedge and an existing conservatory. To make it work, we had to be clever with machinery. We excavated 11 cubic metres of soil, which came to roughly 20 tonnes. To get this done, we used a doorway-sized excavator and our JCB high-tip track dumper. A big thank you to Farr Groundworks for supplying the mini excavator and driver.

Storage space for the muck away was also limited, especially as the driveway, which we extended earlier this year, had to be protected. We laid a plastic membrane and boarded the area with OSB to avoid any damage to the block paving. With access still tight, we brought in Dean’s Grab Service and their four-wheel 10-tonne mini grab lorry. It’s the perfect tool for sites like this.

With the excavation finished, we installed solid 450mm high shuttering, filled the centre of the raft with primary type 1, added a sand blinding layer and laid the DPM membrane. Our raft foundation cages were pre-made in our workshop, allowing us to speed up the process. We tied everything together with full steel mesh coverage.

For the concrete pour, we called on Lancaster Concrete, who supplied both the mix and the concrete pump. With a 46-metre run from the road to the back of the house, the pump made light work of the job. Just over 8 cubic metres of concrete were poured, compacted with a vibrator and finished with a bull float.