RICS Code of Measuring Practice

How do measure an elephant? Carefully and preferably under sedation

So Royal Institution of Chartered Surveyors or RICS created a set of guidelines called the Codes of Measuring Practice or CMP (Please note that RICS has a membership access to its content) to ensure consistency and the application of best practice.

The CMP, which is for UK use only, is "to provide succint, precise definitions to permit the accurate measurement of buildings and land, the calculation of the sizes (areas and volumes) and the description or specification of land and buildings on a common and and consistent basis" (RICS, CMP, A Guide for Property Professionals)

It should be noted that the CMP is different from the Standard Method of Measurement of Building Works (SMM) which is used in the construction industry.

The principal methods of CMP used in property valuation are the following:
Gross External Area (GEA)
Gross Internal Area (GIA)
Net Internal Area (NIA)

It should be noted that it is useful to remember the following conversion rates:

1 metre = 3.28 feet
1 square metre = 10.76 square feet
1 hectare = 2.47 acres

1 foot = 0.3 metres
1 mile = 1.6 kilometres
1 square foot = 0.09 square metres
1 acre = 0.4 hectares

The CMP has a use as proved in the case of Kilmartin SCI (Hulton House) vs Safeway Store plc (2006). The code helps to reduce inconsistencies and disputes, the above court case was dependent on the parties interpretation of the NIA.

It is important to state when quoting values per square foot or square metre what the space measurement basis had been calculated.

Valuers should always double check their measurements and vital information before leaving a property. It can be a time consuming exercise, but best to do it the first time. It is thought to be a unreliable practise to rely on calculating measurements using a scaled drawing with a scaled ruler.

Gross External Areas (GEAs)
The area of a building measured externally at each floor level, mainly used for a computational plot ratio, planning matters or for building costs for residential building. It includes all external wall thicknesses and takes each floor into account.

Gross Internal Area (GIAs)
The area of a building measured to the internal face of the perimeter walls at each floor level. GIA is used for non-residential building costs and the valuation of industrial, warehousing, department, variety, food, retail and new homes for development.

Net Internal Area (NIAs)
The usable area within a building measured to the internal face of the perimeter walls at each level floor level. It excludes the non-usable areas that would be part of a GIA measurement, these may include toilet, toilet lobbies, cleaner's cupboards, lift rooms, stairwells, columns and piers, etc. This measurement is used for the valuation of offices and shops

NB It is essential to refer and apply to the RICS CMP when starting a valuation.

Next time - what is meant by the mathematics of valuation