The standard is the Belgian-adopted version of the European standard for gravity roof drainage . It provides the technical framework for designing, sizing, and installing gutters and downpipes to safely remove rainwater from buildings. Core Purpose and Scope
Based on the importance of the NBN EN 12056-3 standard, we recommend: nbn en 12056-3
For domestic installations, the general rule is a maximum gutter run of 12 metres before an outlet is required. The standard is the Belgian-adopted version of the
One of the most critical clauses in NBN EN 12056-3 mandates that (either via a separate outlet, scupper, or raised curb) capable of handling the 50-year or 100-year rainfall event without water exceeding a safe depth (e.g., 50 mm for waterproofed roofs). This prevents structural overload and ponding on flat roofs. we recommend: For domestic installations
