Prevent water problems on your roof!

For large-scale projects such as distribution centres and logistics buildings, roofs are often constructed in phases. The warm roof panels are already installed, while insulation and waterproof roofing (such as bitumen or EPDM) have not yet been applied.

At this stage of construction, the roof is not yet wind- and waterproof. As a result, precipitation can reach the roof and accumulate in the troughs of the profiled sheets (cannelures). This can lead to unwanted temporary loads and increased risks during execution. SAB offers the solution to this problem with drainage holes in warm roof panels

The problem: water accumulation in the cannelures

When a roof remains exposed for an extended period, rainwater can accumulate in the valleys of the profiled sheet (cannelures). Since no drainage system or waterproof layer is yet in place, this water cannot be discharged.

This can lead to:

● temporary water load on the profiled sheets;
● increased load on the substructure;
● risk of deflection;
● risk of corrosion due to prolonged water exposure;
● disruption of the construction schedule;
● unsafe working conditions (slippery surfaces).

In practice, this is sometimes solved by drilling holes into the roof sheets on site to allow water to drain away. However, this is labour-intensive and poses risks to quality and dimensional accuracy.

The solution: factory-applied drainage holes

SAB offers the option to equip warm roof panels with drainage holes. These are applied during the production process and ensure that water can drain from the cannelures.

This prevents water accumulation and eliminates the need for manual drilling on site.

Technical implementation

The drainage holes are applied according to a fixed configuration:

● Centre-to-centre spacing: 1000 mm
● Offset per valley: 300 mm

This positioning ensures effective drainage of the cannelures without affecting the structural performance of the profiled sheet.