: Drainage must operate without causing danger, nuisance, or damage to building structures or other appliances.

| Part | Title | |------|-------| | EN 12056-1 | General and performance requirements | | EN 12056-2 | Sanitary pipework, layout and calculation | | EN 12056-3 | Roof drainage, layout and calculation | | EN 12056-4 | Wastewater lifting plants |

: For those specifically interested in the roof drainage aspect (linked to Part 3), this design manual provides extensive guidance on applying the EN 12056 standards in practice. Key Content of BS EN 12056-1

is the first part of a five-part European series establishing the general and performance requirements for gravity wastewater drainage systems inside buildings. It applies to systems in residential, commercial, institutional, and industrial settings. Core Requirements of BS EN 12056-1