Performance of siphonic drainage systems for roof gutters

In the first part of the report, the theory of siphonic is explained and descriptions are given of the products currently available in the UK. The similarities and differences between the systems in terms of components and design methods are discussed. Information on in-service performance is also given. The second part describes lab tests carried out at HR on four separate siphonic systems. The final part reviews findings from the first two parts and identifies key issues which specifiers and suppliers of siphonic systems should take into account.