A saddle connection is a branch fitting used to introduce a new lateral pipe into an existing drain or sewer without replacing the whole run. The saddle is shaped to fit over the main pipe, with an opening cut into the host through which the branch flow enters. UK installations follow BS EN 1610 for trenchworks and BS EN 752 for general drainage, and adopted sewer connections require formal approval from the local water and sewerage undertaker, typically Thames Water in Greater London. Saddles can be bonded to clay, PVC-U or concrete host pipes with proprietary sealants or mechanical clamps. Y-junctions are similar in function but supplied as a moulded fitting inserted into the line during new construction. Both should always be installed so that the branch joins at an angle that supports the existing flow direction.
Saddle connection (Y-junction)
Branch fitting allowing a new pipe connection to an existing main drain run.
