Why Belgian TDD is a matter of interpretation

Flemish, French or German documents, legislative variation and insurance access are issues when conducting technical due diligence in Belgium, our third article on the process in other countries explains


  • Adrian Tagg MRICS

01 September 2022

Close up of The Atomium, an atom-shaped building and tourist attraction built for the 1958 Brussels world fair

Close up of The Atomium, an atom-shaped building and tourist attraction built for the 1958 Brussels world fair @ Adrian Tagg

The office sector in Belgium might not seem as glamourous as those in London or Paris. Yet Brussels, Antwerp, Ghent and Liège include a significant number of high-quality commercial buildings.

Of these cities Brussels is the prime location for offices, home to buildings used by the European Commission, EU and the continental headquarters of global companies. Occupancy rates are generally good, and accordingly the quality of commercial buildings tends to be high. Belgium is therefore becoming an increasingly important place for RICS members to operate.

Laws vary but practice often uniform

When it comes to the construction, occupation and operation of commercial property in Belgium, there is often a difference in the legal frameworks that apply depending on the relevant jurisdiction. Belgium is divided into three federal states representing the Flemish-speaking north, the French-speaking south and a much smaller German-speaking enclave to the south east of the country, as well as a separate administrative region representing Brussels.

Therefore, when carrying out technical due diligence (TDD) surveyors must appreciate which legislation is applicable; this is particularly pertinent when reviewing legal or technical documents. In most cases the process is directed by legal advisers, and the nuance in applying legislation often arises when there is a requirement to seek technical advice regarding the compliance of an asset with the applicable law.

Historically Belgium is a country which has been fought over and occupied throughout the centuries, indeed it only gained independent status in 1831. As a consequence of this there appears a unique sense of compromise within the national culture. This flexibility and willingness of individuals or organisations to find solutions to problems appears to permeate into business and often surfaces during the TDD process.

Legislation apart, there is a uniform approach to the relevant construction technology across commercial property. The principal construction elements in Belgium are similar, irrespective of commercial sector or location.

Performance criteria and basic functional requirements for construction elements are likewise identical, or at least similar, to those used elsewhere in the world. Surveyors performing TDD in Belgium will therefore be able to apply most of the principles of technical and construction knowledge they have gained in other countries.

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Concrete common in construction

When conducting TDD in Belgium, surveyors will soon realise that most medium- and high-rise buildings are constructed with reinforced concrete frames. This superstructure form is commonly used in the country because, among other reasons, the relevant natural resources are available to manufacture it cost-effectively.

Generally, the overall quality of reinforced concrete is good; however, as with the widespread use of concrete globally, typical defects can include carbonation and other defects often leading to corrosion of steel reinforcement.

One prominent use of exposed concrete in Belgium is in its brutalist buildings – a term that does not refer to their harsh or abrasive design but derives from the French phrase 'béton brut', which translates as 'raw concrete'. After the Second World War, renowned modernist architects such as Le Corbusier created some iconic brutalist buildings in Belgium.

The exposed reinforced concrete used in such buildings is prone to facade staining, spalling and cold bridging. Given their architectural status, such buildings are increasingly being listed. This should therefore be noted in the TDD process, along with any measures to maintain or renovate the building, particularly in relation to building fabric alterations and upgrades.

'When conducting TDD in Belgium, surveyors will soon realise that most medium- and high-rise buildings are constructed with reinforced concrete frames'

Street level picture of the ING Bank Marnix building, Brussels. The building is partially obscured by trees on the left

While there are a significant number of mid- to late-20th-century office buildings of this kind, the continual redevelopment of the key Belgian cities has resulted in ongoing alteration of the skylines, with seemingly generic curtain-glazed buildings springing up as in other European cities. Again, as on the rest of the continent, the rise of e-commerce and online shopping has stimulated a rapid increase in high-quality logistics sites and data centres, particularly on the arterial roads leading from the port of Antwerp as well as the greater road networks to the East and South of the country.

PII presents difficulty for UK firms

There are not many RICS-regulated firms resident and operating in Belgium that perform TDD. However, a number of traditional, UK-based building surveying businesses provide professional advice or increasingly have branched out to have an office in Belgium or neighbouring EU countries.

Regulated firms are obliged to hold relevant professional indemnity insurance (PII), which will need to cover any TDD carried out in Belgium. Obtaining PII for cladding inspections or fire safety has been tough for British practitioners of late, though, and Brexit has had a further impact on UK-based RICS members operating in Belgium.

Primarily, the range of PII on offer to UK based firms was significantly reduced following the UK's decision to leave the EU; as a consequence, the cost has increased dramatically. UK surveying firms with offices registered in the EU seem to have less difficulty obtaining PII for TDD in Belgium.

Nevertheless, all members performing this service are obliged to observe best practice in line with the current edition of RICS' Technical due diligence of commercial property, guidance note.

Document review demands language skills

It is also necessary to include some form of document review as part of the TDD process in Belgium – and this is where giving advice can become complex.

The documents made available for review in Belgium are mostly in the local language of the administrative body. As this could be in Dutch in French or German – it is paramount that surveyors working on TDD in Belgium are proficient in the relevant language. In instances where surveyors have insufficient linguistic ability, they should seek to work with, or subcontract the document review, to technically qualified native speakers.

The surveyor's role in TDD is to review these documents and report on the findings of others; it is not their position to verify the property's compliance with the law unless they are suitably qualified and explicitly instructed.

International clients unfamiliar with the Technical due diligence of commercial property or working with RICS members often assume that, as appointed experts, surveyors are sufficiently qualified to comprehensively verify buildings' legal compliance. The client instruction should be used to clarify and detail any limitations in the role of the appointed surveyor to avoid any misunderstanding.

Despite the evident cultural and linguistic differences in this relatively small country, English is the language of choice for international acquisition. Accordingly, the TDD report itself, as well as any subsequent sales or purchase agreement for real estate, is invariably written in English.

A similarly universal approach is taken to document review, as per Technical due diligence of commercial property. The following legal and technical documents are typically reviewed, a list of suggested documents is located in the appendix of the guidance note:

  • building permit and permit plans; that is, planning permission

  • environmental permit; that is, an operating permit

  • acceptance certificates; sign off from the architect, design team and authorities

  • fire safety reports, audits, acceptance / sign off from the fire brigade

  • asbestos inventory

  • annual test reports or certificates for electricity, gas, water, lifts and so on

  • energy performance certificates

  • access audit

  • environmental assessment.

This list is of course neither obligatory nor exhaustive, and the client and consultant should use the terms of engagement to agree which documents will be reviewed. As with most legal and technical documents reviewed during TDD, the text is complex and will require practical understanding of the Belgian built environment to interpret it.

'It is also necessary to include some form of document review as part of the TDD process in Belgium – and this is where giving advice can become complex'

Negotiating fire safety complexities

One particular instance of this need to understand the legislative context is that the fire brigade historically stipulates the relevant fire engineering requirements when a building permit is granted. It is therefore the brigade's role to sign this off as part of the acceptance process.

While the written acceptance of the fire brigade often confirms 'Nous n'avons pas des remarques' or 'Wij hebben geen opmerkingen' – that is, 'We have no remarks' – this will often be contradicted by the findings of the TDD inspection.

Fire regulations and other legislation have often been interpreted subjectively by designers and administrators alike when detailing design measures. This is an example of compromises that occur when applying current legislation to existing buildings. However, legal advisers will say that sign-off or approval from the authorities is sufficient. In such situations the TDD report typically notes that, while the relevant sign-off has been received, the survey itself has nevertheless identified specific issues.

Increasingly, fire engineering and cladding are becoming areas of concern with commercial properties. As such there are a number of specialist, qualified control offices; that is, organisations able to audit or sign these issues off as part of the design, execution or TDD process. Such consultants should be appointed in accordance with the process outlined in Technical due diligence of commercial property.

Collaborative expertise can support clients

There are numerous examples of other legal grey areas in Belgian TDD. While the law may appear flexible to outsiders, such issues are often referred back to legal advisers so they can detail the significance of any non-compliance.

In most transactions the legal, technical and commercial due diligence teams have significant specialist experience in these matters collectively to enable them to advise a client together.

Although Brussels is often associated with EU 'red tape' and regulations, the local property and construction laws are applied with the aim of compromising to solve problems. This presents one of the biggest barriers or risks to surveyors performing TDD, as the RICS guidance note does not appear to sanction a 'When in Rome …' approach.

Accordingly, RICS members need to be mindful of the legal requirements of the TDD process, even where they have the necessary technical skill set to advise clients in Belgium.


Adrian Tagg MRICS is an associate professor in building surveying at the University of Reading, founder of Tech DD Ltd and the author of Planned preventative maintenance of commercial and residential property, the RICS global guidance note. He has been performing TDD in Belgium since 2003.

Contact Adrian: Email

Related competencies include: Building pathology, Legal/regulatory compliance

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