Drawing standard – existing and proposed site sections and finished floor/site levels

Where a proposal involves a significant change in ground levels, illustrative drawings should normally be submitted to show both existing and finished levels. These drawings should demonstrate how the proposed development would relate to existing site levels and neighbouring development.

In the case of householder development, the levels may be evident from floor plans and elevations, but particularly in the case of sloping sites it will be necessary to show how proposals relate to existing ground levels or where ground levels outside the extension would be modified.

Level drawings should:

  • show a scale bar or a measured dimension
  • state the existing and proposed levels on the site and where levels differ from that of land immediately adjoining the site
  • be plotted on a plan (scale 1:200 or 1:500), by using spot ground levels at regular intervals in a grid pattern across the site
  • specify a fixed and identifiable datum level, usually “Above Ordnance Datum” (AOD)
  • state the finished floor levels of proposed buildings

Section drawings should:

  • show a scale bar or a measured dimension
  • identify existing and proposed ground levels where significant cut and fill operations are proposed, or where slopes in excess of 1 in 20 exist (or will exist)
  • show “slices” (cross sections) through buildings, normally at a scale of 1:50 or 1:100
  • show “slices” (cross sections) through land, normally at a scale of 1:200 or 1:500
  • be accompanied by a plan showing the points between which the cross sections have been taken, which should also indicate the direction of north
  • show existing and proposed buildings within and adjacent to the site
  • identify finished floor and ridge levels of buildings