ISO 55001 and NEN 2767: what is the difference?

NEN 2767 is the Dutch standard for condition assessment of building and installation parts. The standard describes how you determine the technical state of a building or installation and express it as a number. ISO 55001 is the international standard for asset management . It describes how your organisation manages and improves its assets. The two standards are therefore not the same, but they reinforce each other. For an overview of ISO 55001, start on the main page.

In short, NEN 2767 provides the condition data, and ISO 55001 provides the management system that acts on it. If you only do condition measurements, you know how the assets are doing. If you only have a management system, you do not always know how good the assets really are. You need both to make good decisions.

NEN 2767 measures the state of an asset. ISO 55001 decides what you do with that information: which assets you tackle first, which budget you reserve and who is responsible.

What is NEN 2767?

NEN 2767 is a method for assessing buildings and installations in a consistent way. Its aim is a structured and transparent picture of the technical state of the parts, and of the risks involved. You get a condition score for each part, so you can compare parts with each other.

The standard consists of parts. Part 1 describes the method (NEN 2767-1) and part 2 the defect lists (NEN 2767-2). Check which version applies on nen.nl , because versions can change.

An inspector or measurement company walks past the parts with a defect list. They note where something wears, leaks, rusts or no longer works. This produces a score. The score says something about the condition, not about how important the part is.

What is ISO 55001?

ISO 55001 is a management system. It describes the requirements your organisation must meet to manage its assets well. Think of leadership, planning, the SAMP, risk management, competences and improvement. The standard does not say how a pump should be measured. It does say that you must know how your pumps are doing, and that you base decisions on that knowledge.

Where do they overlap?

The overlap lies in the information. ISO 55001 asks you for reliable data about your assets. This fits with what NEN 2767 produces. Glocert, a certification adviser, points out in a guide that the 2024 version sets stricter requirements for information. These requirements cover data quality, data governance and the lifecycle of data.

An example of the overlap:

Topic	NEN 2767 provides	ISO 55001 requires
State of the assets	Condition score per part	Insight into the asset portfolio
Risk	Defects and their severity	A risk assessment and treatment
Planning	Measurement moments and trend	Planning of maintenance and replacement
Improvement	Comparison over time	Evaluation of effectiveness
Data	Recorded measurement data	Management and quality of information

Example: a municipality with a sports park

This is a fictional example. Municipality Eemvliet manages seven sports facilities. The municipality has a NEN 2767 condition assessment carried out for each facility. This gives a list of parts and their scores for each building: roof, façade, installations and floors.

Those scores do not go straight into the budget. First the municipality looks at the risk. The swimming pool is in poor condition and a failure would have serious consequences, so it gets priority. The municipality consults the municipal council on the budget for the next five years. That part falls under the management system of ISO 55001.

The condition assessment provides the evidence. The management system records what the municipality does with that evidence. You need both, and an auditor asks about both.

When do you need both?

You need NEN 2767 if you want to measure the technical state of buildings or installations, for example for maintenance planning or for a sustainability certificate. The sustainability scheme BREEAM-NL In-Use (the Dutch version of the BREEAM building assessment method) asks, in the draft criteria, for a condition assessment according to NEN 2767 or an equivalent method. Check the final criteria with DGBC (Dutch Green Building Council).

You need ISO 55001 if you want to improve how your organisation manages its assets and show this to a certification body or client. If you only need a certificate, start with ISO 55001. If you only need condition data, start with NEN 2767.

If you want both, start with a condition assessment and then build the management system around it. This way you use the data directly in your decisions.

NEN 2767 does not replace ISO 55001. A condition score for your buildings does not make your organisation a certified asset manager.

Frequently asked questions

Do I have to use NEN 2767 to get ISO 55001?

No. ISO 55001 does not prescribe a specific condition method. You do need to show that you have reliable data about your assets. NEN 2767 is one way to do that, especially for buildings and installations. Ask your certification body whether they accept the method.

Can I carry out a condition assessment myself?

You can, if your staff know the method well and carry out the assessments consistently. You can also have the first assessment done by a specialist firm. This way you know the method is applied properly. Ask your certification body which firms they consider suitable.

Is condition assessment part of ISO 55001?

ISO 55001 covers the management system and does not prescribe a condition method. NEN 2767 is the Dutch method for condition assessment of buildings and installations. For the management side, read the requirements per chapter.