Site area
The New Rules of Measurement (NRM) are published by the Royal Institute of Chartered Surveyors (RICS). They provide a standard set of measurement rules for estimating, cost planning, procurement and whole-life costing for construction projects.
According to NRM1: Order of cost estimating and cost planning for capital building work, the term ‘site area’ (SA) means:
‘…the total area of the site within the site title boundaries (or the total area within the site title boundaries defined by the employer as the site for the building), measured on a horizontal plane.’
However, NRM1 then goes on to give a second, slightly different definition:
‘Where the external works is to be measured separately, the site area (SA) is to be measured. The SA is the total area of the site within the site title boundaries (or the total area within the site title boundaries defined by the employer as the site for the building or buildings), excluding the footprint of the new building(s), measured on a horizontal plane.'
Land measurement for planning and development purposes, Guidance Note, Global 1st edition, Published by the Royal Institution of Chartered Surveyors (RICS) in May 2021, suggests that: ‘Site area is the total land area for which development authorisation is sought, measured on a horizontal plane.’
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