- Project plans
- Project activities
- Legislation and standards
- Industry context
Last edited 30 Jan 2019
Gross external area GEA
It is very important to be clear about which measure is being used, for example in property sales, planning applications, building regulations applications, lease negotiations, rating valuations and so on.
The UK government’s Valuation Office Agency (VOA) Code of measuring practice: definitions for rating purposes suggests that ‘gross external area’ refers to the whole area of a building taking each floor into account, including perimeter walls. This includes:
- Perimeter wall thickness and external projections.
- Areas occupied by internal walls (whether structural or not) and partitions.
- Columns, piers, chimney breasts, stairwells, lift wells, and so on.
- Lift rooms, plant rooms, tank rooms, fuel stores, whether or not above roof level.
- Open-sided covered areas (should be stated separately).
Gross external area excludes:
- Open balconies.
- Open fire escapes.
- Open sided covered ways.
- Open vehicle parking areas, terraces and so on.
- Minor canopies
- Any area with a headroom of less than 1.5 m (except under stairways).
- Any area under the control of service or other external authorities
According to NRM1: Order of cost estimating and cost planning for capital building work, the gross external area is '...the area of a building measured externally (i.e. to the external face of the perimeter walls) at each floor level.The rules of measurement of gross external floor area are defined in the latest edition of the RICS Code of Measuring Practice.'
The VOA Code of measuring practice is in general agreement with RICS Guidance Note, A guide for Property Professionals, 6th Edition Code of measuring practice 2007, other than, areas with a headroom of less than 1.5m which are excluded from the VOA measurement.
 Related articles on Designing Buildings Wiki
Featured articles and news
A quality perspective.
If buildings were people, they would be just starting to walk on two legs.
Air filtration and clean air standards.
The Dukes of Normandy and the second world war.
Conserving structures in historic designed landscapes.
Online platform to showcase acoustic solutions.
The drivers of value and how it is measured.
Do you know your Ionic from your Doric?
Construction output has been stronger than anticipated.
But blame is directed at the construction industry.
Health effects on children and young people.