Siphonic Drainage Technical

Our suppliers UK Siphonix undergo regular Roof Drainage Design Software System checks and are validated by CRM Rainwater Drainage Consultancy Ltd at their laboratory facility in Bolton, UK. CRM Rainwater Drainage Consultancy Ltd are one of the foremost authorities on siphonic roof drainage in the UK. UK Siphonix complies with the requirements of BSEN12056-3:2000 and BS8490:2007.

In addition CRM's testing also confirms that the Siphonix SX75 and SX110 siphonic roof outlets conform to the performance requirements of BSEN12056-3:200, BS8490:2007 & ASME 112.6.9-2005.

SX75 Siphonic Roof Outlet

Siphonix SX75 Stainless Steel Siphonic Roof Outlets c/w Membrane Clamp Plate, HDPE Air Baffle Lid & Spigot Flexseal Coupling.

Air Baffle

Conforms with performance requirements of BSEN12056-3:2000, BS8490:2007 & ASME 112.6.9-2005.


HDPE Pipe System

Row of siphonic Tailpipes connected to High Level Horizontal PE Fully Welded Siphonic Collector / Header Pipe.

Air Baffle

This HDPE Pipe System used throughout our projects is also known as SDR26 PE80 Polyethylene Pipe. The priming tailpipes will quickly fill this horizontal collector as storm continues pushing plugs of air along the collector until water reaches and discharges down the downpipe exploiting the disposable head provided by the height of the building pulling all water behind to induce a full bore siphonic flow throughout the whole system.

This process reverses as storm / precipitation subsides.

Air Baffle & Outlet into Tailpipe

SX75 Siphonic Roof Outlet connected to Vertical and Horizontal PE Fully Welded Tailpipe. This process reverses as precipitation subsides.

Air Baffle and Outlet into Tailpipe

These tailpipes will prime very quickly when precipitation / storm approaches design rainfall intensity to induce initial siphonic flow.


Unistruct Bracket System

Illustration of Fully Railed Siphonic Collector Pipe using Slotted Unistrut Type Rail and Mupro Type Pipe Clamps.

Air Baffle and Outlet into Tailpipe

The rail is designed to restrain thermal movement of the siphonic pipework and should be fixed to structure at maximum 2m centres.

Why work with us?

Our commitment to quality is a cornerstone of our business, as well as holding ISO accreditation ourselves, we ensure that all products sold by us are manufactured by ISO certified companies.

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