Measurement

Question 1

Why is measurement important?

Answer 1

Measurement is important because it underpins almost everything we do as surveyors. Accurate measurement is the foundation of providing reliable valuation advice — if the area is wrong, the value will be wrong. Even small inaccuracies can make a significant difference, particularly in valuation, rating and taxation work. It also ensures consistency and fairness for stakeholders, whether that’s owners, tenants, lenders or the Assessor’s office. Ultimately, accurate measurement gives confidence in the figures we report and maintains our professional credibility.

Question 2

Why does measurement need to be accurate?

Answer 2

Measurement needs to be accurate because the figures we provide directly feed into the values we produce. If the measurements are wrong, the advice and values that follow will also be wrong, which can lead to unfair outcomes, financial loss and a loss of confidence in our professional judgement.

Question 3

Who relies on floor areas?

Answer 3

occupiers
valuers
insurance assessors
planners
lenders

Question 4

What is the purpose of the code of measuring practice?

Answer 4

It is the long establilshed UK standard. Provides precise definitions to permit the accurate measurement of buildings and land and the calculation of areas on a common and consistent basis.

Question 5

What are the IPMS and why were they introduced?

Answer 5

IPMS is the global standard, a set of internationally adopted measuring standards that aim to provide a consistent measurement of property, across the world.

Property data and language is consistent and transparent globally.

The consistency helps international property trade

Question 6

How many IPMS bases are there?

Answer 6

6 (including the 3.1,3.2,4.1,4.2)

Question 7

What are the bases and what do they equate to in terms of the CoMP?

Answer 7

IPMS 1: closely equates to GEA
IPMS 2: closely equates to GIA
IPMS 3: equates somewhat to former NIA
Includes 3.1 and 3.2
IPMS 4: equates somewhat to former NIA (Selected Floor Areas)
Includes 4.1 and 4.2

Question 8

What is the Internal Dominant Face (IDF)?

Answer 8

It is the internal surface comprising more than 50% of the floor to 2.75m height for each IDF wall section.

Question 9

What are components as included in IPMS 1 & 2?

Answer 9

This allows surveyors to break down the total building area into identifiable parts. Instead of just giving one total floor area, IPMS allows the surveyor to identify and report specific parts of the building separately.

For example, areas may be identified such as plant rooms, balconies, circulation areas etc

These are not separate measurements, but sub-categories of the total measured area.

Question 10

What are component areas?

Answer 10

It is the total floor areas attributed to one of the components, e.g:
A - Vertical Penetrations (stairs, lift shafts/ducts)
B1 - External Wall (ext enclosure of a building, which comprises area between IDF and outside face of a building)
B2 - Internal structural walls/columns
B3 - Internal non-structural elements (all internal, full heigh, permanent walls)
C - Technical Services (plant rooms, motor rooms, maintenance rooms)
D - Hygiene Areas (toilets, cleaners cupboards, bath/shower rooms, changing rooms)
E - Circulation Areas (measured horizontally)
F - Amenities (cafeterias, day-care, sport and fitness/leisure areas, prayer rooms)
G - Living space (area available for use by residential occupiers)
H - Other areas (balconies, covered galleries, car parking, storage rooms)

Question 11

What is the RICS Code of Measuring Practice?

Answer 11

A UK based measurement standard developed by the RICS which defines the traditional area bases such as GEA etc.
Still used in valuation/rating but departures from IPMS office or residential need to be recorded.
6th edition was published in 2015, and the 7th edition is planned for 2026.

Question 12

What are the core definitions under the CoMP?

Answer 12

GEA (Gross External Area)
GIA (Gross Internal Area)
NIA (Net Internal Area)

Question 13

What is IPMS 1?

Answer 13

The Floor Area measured to the external extent of the External Walls and to any Notional Boundaries,
External Floor Areas or Sheltered Areas.

(Notional boundary = imaginary measurement line used where no wall exists.)

Question 14

What is IPMS 2

Answer 14

The Floor Area measured to the internal extent of the IDF and to any Notional Boundaries and External Floor Areas.

Question 15

What is IPMS 3.1 - Exclusive Occupation External Measurement

Answer 15

The Floor Area available on an exclusive basis to an occupier measured externally to any Notional Boundaries, External Walls, Demising Walls and including any External Floor Areas, Sheltered Areas and Secondary Areas.

Question 16

What is IPMS 3.2 - Exclusive Occupation Internal Measurement

Answer 16

The Floor Area available on an exclusive basis to an occupier measured internally to any Notional Boundaries, the Internal Dominant Face, Demising Walls and including any External Floor Areas, Sheltered Areas and Secondary Areas.

Question 17

What is IPMS 4.1 - IPMS for Selected Floor Areas

Answer 17

The selected Floor Area in a Building measured to Finished Surfaces and to any Notional Boundaries, External Floor Area and Sheltered Area including all Floor Area occupied by Walls and Columns

Question 18

What is IPMS 4.2 - IPMS for Selected Floor Areas

Answer 18

The selected Floor Area in a Building measured to Finished Surfaces and to any Notional Boundaries, External Floor Area and Sheltered Area but excluding (subtracting) all Floor Area occupied by Walls and Columns.

Question 19

What is GEA?

Answer 19

Area of building measured externally at each floor level.

Question 20

What does GEA exclude?

Answer 20

Fire escapes
Canopies
Parking areas, roof terraces
Voids
Greenhouses/garden stores

Question 21

What is GIA?

Answer 21

Area of a building measured to the internal face of the perimeter walls at each floor

Question 22

What does GIA exclude?

Answer 22

As GEA as well as perimeter thickness of walls and external projections.

Question 23

What is NIA?

Answer 23

Useable area within a building measured to the internal face of the perimeter walls at each floor level of a building.

Question 24

What is excluded in NIA?

Answer 24

entrance halls, atria, landings and balconies used in common.
toilets, lobbies, bathrooms, cleaners rooms.
lift rooms, plant rooms, tank rooms, fuel stores
stairwells, lift-wells and permanent lift lobbies
corridors/other circulation areas used in common.
areas under control of service or other external authorities.
internal structural walls, columns and pillars.
space occupied by air-con apparatus.
areas with headroom less than 1.5 m
vehicle parking areas.

Question 25

How is retail property measured?

Answer 25

The zoning principle.

Question 26

What is the Zoning principle?

Answer 26

Premise that the front of the shop is the most valuable and the value to the occupier decreases the further back of the property you go.

Question 27

How much does each zone decrease in the zoning principle?

Answer 27

50%

Question 28

What are some tools for collecting accurate measurement data?

Answer 28

Laser measure(distometer) Measuring tape Tape Measure Measuring Rod Feet (if necessary) Digital mapping such as GIS Scale rulers/plans

Question 29

Could you give me some examples of some of the advantages and disadvantages of lasers/distos?

Answer 29

They are fast, usually accurate to 1.5mm and can be operated alone. They can be inaccurate in bright light or sunshine and must be maintained/calibrated for accuracy.

Question 30

Could you give me some examples of some of the advantages and disadvantages of other methods?

Answer 30

Tapes can sag or stretch. Trundle wheels are inaccurate on rough ground. GIS depends on accurate mapping data. All are prone to human error.

Question 31

What is GIS and how is it used?

Answer 31

A Geographic Information System is a platform that can measure large areas such as site areas, and plot land boundaries and ownership area.

Question 32

What are the limitations of using existing plans when measuring a property?

Answer 32

Existing plans may be outdated, not to scale or design intent, leading to inaccuracies in measurements.

Question 33

What is the current RICS approach to Japanese Knotweed and how does it affect valuation?”

Answer 33

RICS’ 2022 Professional Standard ‘Japanese Knotweed and Residential Property’ replaced the old seven metre rule risk categorisation based on visibility, location and impact. As valuers, we must identify it, classify the risk appropriately, and advise whether a professional management plan is required.

Question 34

What makes a valuation Red Book compliant?

Answer 34

A valuation is Red Book compliant when it follows the RICS Valuation – Global Standards (effective 31 January 2025), which align with the International Valuation Standards. This means complying with mandatory Professional Standards — PS 1 and PS 2 — and the relevant Valuation Technical and Performance Standards covering terms of engagement, bases of value, assumptions, inspections, valuation methods and reporting. The 2025 edition also strengthens Envoronment, Social, Governance, modelling and technology requirements. compliance is evidenced through clear terms of engagement, a stated basis of value, documented assumptions and scope, proportionate inspection/investigations, transparent analysis, and a reasoned valuation conclusion.

Question 35

What is the primary difference between the 2023 version of IPMS and the previous versions?

Answer 35

It established a single harmonised framework for all building types instead of separate standards.