BS 8490:2007

This standard BS 8490:2007 Guide to siphonic roof drainage systems is classified in these ICS categories:

• 91.060.20 Roofs
• 91.140.80 Drainage systems

This British Standard applies to roof drainage systems using circular-section pipes that operate under siphonic action. It does not apply to siphonic drainage systems using rectangular or trapezoidal section conduits for water conveyance.

It gives information and provides guidance on design parameters, installation, verification and maintenance needs of siphonic roof drainage systems conforming to the performance requirements specified in BS EN 12056‑3:2003, 6.2. Guidance is also given on carrying out checks of designs, for the use of specifiers and regulatory authorities.

Particular issues for site drainage systems that receive flows from siphonic roof drainage systems are also covered.