Office obsolescence in Belgium: Up to €22 Billion in retrofit required

JLL’s latest analysis lays it out clearly: over 13.1 million m² of office space in Brussels, 65% is considered obsolete (Grade C). The situation is even more pressing in areas like the North Quarter, where that number climbs to 66%, and the city’s periphery, reaching 69%. 

This isn’t just a Brussels issue.

In Flanders, 50% of the region’s 5 million m² of office stock is Grade C. In Wallonia, the picture is equally concerning, with half of all office space in need of revalorisation. These figures highlight a national-scale urgency—but also a once-in-a-generation opportunity to reinvent, revalorise, and reposition Belgium’s real estate for a sustainable, high-performance future.

Because the real question is no longer whether to act—but how to revalorise.

The conventional idea of renovation is being outpaced by the climate crisis, ESG requirements, and tenant demands for comfort and efficiency. Energy costs, sustainability standards like BREEAM or WELL, and the European Taxonomy are pushing buildings to deliver more than just compliance—they must now demonstrate future-proof value.

At pulse, we don’t think renovation. We think revalorisation: a full-spectrum strategy combining technical upgrades, ESG alignment, and design for well-being, all within an ROI-driven framework.

JLL estimates the cost of upgrading Belgian offices between €1,800 to €2,500/m², with Brussels leaning toward the upper end of the scale. That translates into  an investment of €12.7 to €15.8 billion in Brussels alone, for the 6.3 million m² in need of heavy renovation.

In Flanders, approximately 2.5 million m² of office space requires revalorisation, amounting to an estimated €4.5 to €5 billion. Wallonia, with about 0,863 million m² in need, would necessitate €1.5 to €1.7 billion. 

It’s a national-scale investment challenge, but one with high returns: increased rental value, improved asset liquidity, and alignment with both investor and regulatory standards.

Let’s not forget the real prize: transforming old stock into sustainable, attractive, and high-performing real estate. That means not only reducing CO2 emissions but also increasing tenant comfort and generating measurable returns. In Brussels, where demand for top-performing buildings exceeds supply, now is the time to act.

As JLL’s report shows, obsolescence is widespread—but so is opportunity. The next move belongs to you.

At pulse, we advocate proactive, not reactive strategies. From performance assessments in energy, comfort, and well-being to decarbonisation strategies, permit management, and execution, our pulse Consultancy, Serenity, and Energy services help investors tackle the full journey with one single partner.

More info: JLL report "Opportunities through obsolescence"