Upgrading dormer window waterproofing system

The issue: Leaking roof dormer windows

Our client contacted us after experiencing water ingress around multiple dormers, with tiled interfaces and perimeter channels allowing moisture penetration. The existing detailing was no longer providing reliable weather protection, and a long-term solution was required.

Following a full inspection, we provided a detailed quotation outlining the recommended remedial works. Once approved, the project was scheduled to commence promptly.

Works Completed

Our expert roofing team began by removing the tiles from the two affected dormers to fully expose the underlying structure. This allowed us to address the root cause of water ingress rather than applying a temporary fix.

Key works included:

• Encapsulating each dormer with a high-performance two-layer felt system, creating a continuous and robust waterproof barrier

• Installing new return drip edges to improve water runoff and prevent moisture tracking at vulnerable junctions

• Carefully reinstating the original tiles, ensuring both performance and aesthetic appearance were maintained

• Clearing all drainage channels to four dormers around the property’s perimeter, ensuring unobstructed water flow and reducing the risk of pooling or overflow

All works were carried out with attention to detail and using high-quality materials to guarantee long-term durability.

Outcome

The dormers now benefit from a fully upgraded waterproofing system with improved edge detailing and enhanced drainage. The works have significantly increased resilience against driving rain and prolonged exposure to the elements, providing reliable, long-term roof performance.

By addressing both the waterproofing and drainage, this solution ensures that the dormers are protected from future water ingress, reducing maintenance needs and extending the roof’s lifespan.