The groundworks

Groundworks is an all-embracing term covering the various tasks needed to prepare you site for the build. This includes all site clearances - which may involve demolition of existing structures - as well as earth movements, reducing levels to establish a datum (the reference from which measurements will be taken from during construction) and excavations.

This stage would typically also cover service and drainage supplies - including temporary outlets - but these are a major topic in their own right, so we’ll be covering them in next month’s article. We’re also assuming that forming a construction access to the site would be accounted for in  your preliminary costs.

This is an edge-of-settlement infill plot, previously used as garden space for a neighboring house. While it’s not strictly Greenfield (undeveloped) land, our virtual site has never had a structure built on it - so we’re not facing any demolition works. We must still clear the site of all loos plant growth, as well as generally reduce levels, by scraping away 30mm of top soil over 225n2 formation area (to allow for full access during the works). Where possible, it’s best to retain this material for re-use - both to save money and because it’s likely to be the most fertile soil for planting schemes at the end of your project.

Accuracy at the groundworks stage is important on any build, but particularly when you’re working with timber frame. We intend to erect 300mm-thick external walls in the centre line of a 600mm-wide foundation. Our groundwork will set out chalk lines and operate the plant to excavate to the right depth, which would be established using profile boards, We need to dig 35m3 of foundation trenches, with the waste bulking up to around 70m3 of muck away.

All project will involve a series of initial cost, which we’re factoring as extras to the construction of the house.