Absolute Survey Ltd produce a Net Internal Area
which provides the usable area within a building
at each floor level. This calculation is critical for
valuation, marketing and property rating purposes.
Area surveys are carried out in accordance with
the RICS code of measurement practice.
Lease plan surveys can be produced to give
accurate floor plans, providing the client a plan
to be used in space planning or building details
Area Surveys consist of three main core areas:
Gross External Areas (GEA), Gross Internal
Areas (GIA) and Net Internal Areas (NIA). NIA
is the most widely used discipline of Area Surveys
but depending on the requirements of clients it
may be necessary to undertake GEA’s and GIA’s.
Each core area is measured in much the same way and thus it is necessary to establish a best measurement practice for Area Surveys so as to standardize the process from fieldwork to the final deliverable.
The basis for the following definitions is the Code of Measuring Practices (5th Edition)
Gross External Area is the area of a building measured to the outside face of the perimeter wall at each floor level.
- Perimeter wall thickness and external projections.
- Areas occupied by internal walls and partitions.
- Columns, piers, chimney breasts, stairwells, lift-wells, and the like.
- Atria with clear height above, measured at base level only (stated separately).
- Internal balconies.
- Covered: lift rooms, plant rooms, fuel stores, tank rooms which are housed in a structure of a permanent nature whether or not above main-roof level (stated separately).
- Outbuildings, which share at least one wall with the main building (stated separately).
- Loading bays (stated separately).
- Areas with headroom of less than 1.5m (stated separately).
- Pavement vaults.
- Service Accommodation such as toilets
- Open balconies.
- Open fire escapes.
- Open-sided covered ways and minor canopies.
- Canopies (state separately).
- Open vehicle parking areas, terraces and the like.
Town Planning:GEA is the basis of measurement for planning applications and approvals, i.e. site coverage (including plot ratio).
GEA is the basis of measurement for Council Tax banding for houses and bungalows (areas with a headroom of less than 1.5m being excluded), and for rating of warehouses and industrial buildings in Scotland.
Building Cost Estimation:
GEA is the preferred method of measurement for calculating building costs of residential property for insurance purposes.