The roof is leaking again, and it was repaired just two years ago! Time to call back the waterproofers!
But wait—before rushing to conclusions, it’s important to consider whether the waterproofing company is always to blame. There are various reasons why a roof might leak after the waterproofing work has been completed. Let’s explore two illustrative case studies:
Case Study One
An upmarket house with a flat concrete roof was covered with high-quality torch-on waterproofing approximately 12 years ago. The roof began to leak, but only during heavy rain, with water seeping through the top of the window reveal and splashing onto the window sill.
An investigation of the flat roof revealed that the waterproofing was in perfect condition, and the area where water was entering was actually at the high point of the roof. A closer inspection of the wall revealed large cracks, and when examined immediately after the rain, it became evident that water was entering the building through the vertical face of the wall.
Case Study Two
A commercial building in the CBD recently underwent specialist refurbishment on its roof. The spray-on polyurethane foam layer was refurbished and overcoated with a high-tech siliconised waterproof coating.
Six months later, the building owner contacted the waterproofing contractor to report that the roof was leaking. When the contracting company inspected the roof, they discovered a multitude of issues.
A vent pipe had been installed by another company and not been sealed 
There were some cuts to the waterproofing coating in the immediate vicinity of the pipe 
There were also holes in the waterproofing in the immediate vicinity of the vent pipe 
There were numerous sharp nails and screws lying around on the roof 
Building rubble was left in the roof 
An outlet pipe was blocked with a huge pool of water standing on the roof. Amazingly there were no leaks in this area, showing how good the coating is
Conclusion
There are many factors that can lead to water ingress in buildings. As demonstrated in the case studies above, the first instance wasn’t due to a fault with the roof, and in the second case, the Roofing Contractor was not to blame.
However, building owners are rarely experts in these matters, so if in doubt, it’s always wise to call the waterproofer. A reputable contractor should be able to quickly identify whether the issue is their responsibility and, if so, honour their guarantee by carrying out repairs as promptly as possible.
If the issue lies elsewhere and is not the fault of the Roofing Contractor, it would be fair for the Building Owner to receive a reasonable quote for the additional work needed.
It’s also important to note that Building Owners have obligations in terms of routine maintenance, such as ensuring that the waterproofing is not damaged and that all outlets remain unblocked. Regular upkeep can prevent many common issues and prolong the lifespan of the waterproofing system.
