Rat barrier

[sqidd1g]

I have been asked to put a rat barrier within a domestic drainage system.
The only unit I have been able to find is a Hepworth product which normally sits at base of SVP / soil stack.
The drainage in question runs from exterior of property through a final i/c in the basement to mains sewer.
As far as I know the rats are entering the system from the mains sewer, thus the ideal position to place a barrier would be downstream of the final basement i/c.
However, the unit itself is 1.125m in height and I am unsure whether there will be enough depth from the final basement i/c to the mains sewer.
Does anyone know of another type of rat barrier or has anyone had this problem?
Any help greatly appreciated

sqidd1g

[Tony McC]

Have you had a look at the Polypipe or the Wavin offerings? Although they are primarily intended for uPVC system, they can (or they ought to) be capable of being retro-fitted to any residential drainage system.