When water wins: iconic buildings affected by waterproofing failures

 

Water can be one of the greatest enemies of civil construction. It escapes the eye, seeps through small cracks and gradually weakens structures that seemed indestructible. By the time signs appear, it may already be too late: damp patches, accelerated degradation… and, in extreme cases, evacuation of world-famous buildings.

Therefore, when waterproofing fails, not even the most iconic buildings are safe. The examples we present today, separated by centuries and continents, prove that the fight against water is constant, requiring vigilance and maintenance. Shall we take a look at them?

 

 

 

How water compromises structures over time

 

Water infiltration does not always cause immediate damage. It starts with small leaks in the seal, almost invisible cracks or poorly treated joints. Over time, this constant moisture compromises structural elements, causing:

 

• Oxidation of iron reinforcement in concrete;
• Detachment of coatings such as tiles and plaster;
• Thermal and acoustic degradation of insulation;
• Mould and fungi, with implications for health.

 

Real cases where water won: lessons from world architecture

 

1. British Museum (London)

In the heart of London, the British Museum houses treasures of human civilisation. However, in recent years, the institution has faced repeated leaks from the old roofs, forcing the temporary closure of galleries and the adoption of emergency measures such as buckets to collect water.

 

The causes? Ageing waterproofing systems and natural wear and tear, typical of buildings that have been in use for centuries. The interventions have been sporadic, but the museum knows that a major renovation plan is inevitable to safeguard its collection.

 

 

2. Sydney Opera House

Famous for its silhouette of white ‘shells,’ the Sydney Opera House also faced waterproofing challenges.

 

Over the years, the joints between the precast roof panels developed cracks and wear, allowing water to seep in. The result was a series of technical interventions to seal and permanently monitor moisture, preventing the problem from developing into more serious structural damage.

 

 

 

3. TWA Terminal – JFK Airport (New York, USA)

 

The terminal, designed by Eero Saarinen, is an architectural masterpiece. But over the years, small leaks in the curved roof have also required constant repairs. Here, the difficulty was not only technical; it was also aesthetic, as any intervention had to respect the original shape and design.

 

What went wrong? Difficulty in adapting waterproofing solutions to complex and unconventional structures.

 

 

4. Louvre Museum (France)

In May 2025, a severe hailstorm hit Paris and damaged a section of the Louvre’s glass roof. The impact damaged the sealant, allowing water to enter a room where a painting by Cimabue was on display. The room was evacuated and the fire brigade called, but no damage to the artwork was reported.

 

This episode highlighted how even small flaws in the waterproofing of complex roofs can suddenly put priceless heritage at risk.

 

 

5. Millennium Tower (São Francisco, EUA)

This luxury skyscraper, inaugurated in 2009, became known for two reasons: slowly sinking and leaks in common and underground areas. Poor waterproofing allowed water to enter the garage and foundations, aggravating existing structural problems. This project failed to provide effective protection against groundwater and drainage, which was poorly designed.

 

 

 

Why does this happen even in large projects?

 

Despite technical advances, waterproofing failures continue to occur with surprising frequency. But why?

• Design and execution errors
  Often, problems begin right at the design stage. Poorly designed details, inadequate finishes, or ineffective drainage solutions are errors that only become apparent years later.
• Inappropriate materials
  The use of low-quality materials that are not suited to certain climatic conditions or applications is a common and costly mistake. A poor choice today can mean leaks tomorrow.
• Lack of maintenance and regular inspections
  Proper waterproofing requires maintenance. Regular cleaning and inspections allow problems to be identified and addressed before they become serious.

 

Lessons for the future

 

These cases show that:

• Waterproofing is not permanent and requires scheduled maintenance.
• Extreme weather events accelerate the revelation of hidden defects, and small flaws in joints or seals can have major consequences for the property.
• Bold architectural solutions can pose major challenges for waterproofing projects, which should be given special attention.

 

Whether it is a historic building or a new construction, protecting against leaks means protecting the structure, safety and even the reputation of the project.

 

At Prudêncio, we know that every roof has its own story, and that every detail counts to ensure that water never wins.