APC Measurement skills

What do candidates need to do to achieve the Measurement competency in their APC? The latest in our series on core commercial competencies explains


  • Jen Lemen

23 May 2020

Measurement has been a core competency to Level 2 on the Commercial Real Estate APC pathway since August 2018, as it was on the previous Commercial Property pathway; it is also an optional competency on various other related pathways.

It is very rarely taken to Level 3 by Property pathway candidates, as this would require specialist knowledge and experience of sophisticated measurement and data collection practices. This means that at Level 2, candidates need to include in their summary of experience or case study some practical examples of their knowledge of data collection and measurement of land and property.

Accurate measurement is fundamental to providing prudent property advice, particularly when it comes to the measurement of saleable or lettable areas for agency or valuation instructions. Candidates therefore need to remember that even minor inaccuracies in measurement can lead to substantial variations in value, especially in high-value locations.

"Accurate measurement is fundamental to providing prudent property advice"

Tools and techniques

Candidates should be familiar with data collections techniques such as a tape rod laser distometer and trundle wheel.

The laser distometer is the primary measurement tool that candidates are likely to use for measuring property; this sends a pulse of laser light to a target, measuring the time it takes for the reflection to return. More advanced lasers can also be used that add and subtract measurements and carry out various area calculations.

Laser distometers are typically accurate to within 1.5mm or less over distances up to 200m, although this will depend on the device used. Annual calibration is important to ensure accuracy, typically by sending the laser distometer back to the manufacturer. Taking check measurements over a known distance can also ensure accuracy on a more frequent basis. Leica provides a clear methodology for doing so on its website.

The benefits of using a laser distometer are accuracy and ease of use. However, it is not without its limitations: it does not function well in bright light and is difficult to use in very narrow spaces. This is where other tools such as tapes and rods come in. These can be used in tight spaces or to measure behind a tenant's fit-out works. for example in a shop. Again, limitations need to be considered, such as inaccuracies where a tape bends or sags. Finally, a trundle wheel can be used to measure substantial external distances such as a plot of land.

There are many steps candidates can take to ensure that their measurements are as accurate as possible including:
  • taking several check measurements
  • making sure the laser or tape is measuring from the correct surfaces
  • checking measurements with scaled plans or reliable mapping software
Measurements should primarily be stated in metric units, although clients will often also request imperial conversions from metres to feet, square metres to square feet, and hectares to acres. Candidates should also be aware of different scales used on maps and plans such as 1:50 for a single room or 1:1,250 for a street plan.

Furthermore candidates must be familiar with the latest RICS guidance on measurement namely the Property measurement professional statement second edition, effective since 1 May 2018. This includes the International Property Measurement Standards (IPMS) for residential and office property while the former Code of Measuring Practice (CMP) still applies to industrial retail and other property types.

Although IPMS for retail and industrial have now both been published, RICS does not yet include them in the professional statement but Part 1, 'Application of this professional statement' applies to all asset classes. Candidates should therefore stay abreast of changes to ensure that they are measuring to the correct bases and are familiar with any changes for their APC final assessment interview.

Candidates should also be aware of the requirements for dual reporting, where a client can request that this be done on both IPMS and CMP bases. However, sole use of CMP bases should be avoided where IPMS has been adopted by RICS.

Some key definitions that candidates should be aware of include the following:

  • Common facilities

    Those parts of a building providing shared facilities that typically do not change over time including circulation areas stairs escalators lifts and motor rooms toilets plant rooms cleaners cupboards fire refuge areas maintenance rooms and unallocated parking spaces.

  • Component area

    The extent at ground level of the area of a building covered by one or more roofs the perimeter of which sometimes referred to as the drip line is the outermost structural extension exclusive of ornamental overhangs.

  • Finished surface

    The wall surface directly above the horizontal wallfloor junction ignoring skirting boards cable trunking heating and cooling units and pipework.

  • Internal dominant face (IDF)

    The internal finish comprising more than 50 per cent of the floor-to-ceiling height for each external wall section; if this does not occur the finished surface is deemed to be the IDF

  • IDF wall section

    Internal finish of a section of an external wall ignoring any section columns that is either recessed from or protrudes from its adjacent section.

Candidates may come across the term 'limited-use areas'; these are included in floor areas, but stated separately. There is no one definition of a limited-use area as they differ between markets, however they may include limited head height, limited natural light or areas below ground.

The key measurement bases of which candidates should be aware for agency and valuation work are as follows:

  • Offices

    IPMS 3 roughly equivalent to the net internal area (NIA) from the CMP this includes all internal walls and columns within the area available exclusively to an occupier but excluding standard facilities.

  • Retail

    The NIA which is the useable area measured to internal face of perimeter walls at each floor; sometimes GIA may be used for larger units such as supermarkets or department stores.

  • Industrial

    GIA measured to the internal face of perimeter walls at each floor.

In the competency guide, RICS sets out the following examples that would be appropriate at Level 2:
  • using the appropriate instrumentation including lasers and tapes to collect sufficiently accurate data based on an understanding of the limitations of different instruments
  • dealing with and advising on sources of error from use of instruments
  • applying the appropriate guidance correctly in practice to measure a variety of properties, understanding the basis on which measurements should be made
  • making necessary calculations
  • preparing and presenting measurements in a manner appropriate for the purpose
Candidates need to make sure that they have practical experience of measuring a variety of property types. This experience should be built up over time so they are sufficiently familiar with measuring accurately and adhering to the relevant RICS measurement bases.

When on site, candidates should lead measurement exercises and ensure they understand terminology such as the IDF. This may follow a period of helping others with measurement in order to understand the reasons why accurate measurement is so important and how it is done.

The measurement bases can be confusing, as the differences can be subtle. It is always helpful, therefore, to take a copy of the RICS guidance on site to ensure accuracy and avoid the need to repeat measurements. Getting it right at the start can save a lot of time later, particularly where high-value properties are being measured for agency or valuation purposes.

Candidates can take the following steps to help them succeed in measurement:
  • They should practise measurement as often as possible, measuring the property or land for each and every instruction, even measuring their own office or house in preparing for the final APC assessment
  • The RICS guidance should be read and referred to on site to ensure measurement is made on the correct basis. The guidance includes colour-coded diagrams that are an excellent visual aid
  • Keep up to date with any changes to IPMS and RICS guidance. IPMS for retail and industrial have both been published; although they have not yet been adopted by RICS, the next edition of the Property measurement professional statement could do so so be aware of publication dates
  • Taking check measurements on the same visit will enable mismeasurements or misrecorded measurements to be identified
  • In large buildings or challenging configurations, measuring with a colleague can help, especially if one person takes measurements as the other records them

"Candidates should be aware of requirements for dual reporting where a client can request this be done on both IPMS and CMP bases"

Related competencies include: Measurement

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