Hi everyone - thanks in advance for your thoughts on this and sorry if I mix up any technical terms, I've been googling a lot. We're planning on updating a downstairs cloakroom toilet in a 1960s/1970s Council house. The toilet is part of maybe a 1.5m x 1.5m single storey "extension" that all houses on the street have. There are two other drains outside: The driveway drain, which is in the middle of the driveway and rainwater flows into this (most of the time!). The kitchen sink drain, which is right next to the house and is where the kitchen sink discharges into. In the toilet, we've opened up the basin vanity and can see the waste pipe goes from under the basin straight through the internal and external walls (cavity wall) and then drops into the gravel / ground in the front garden / driveway (please see pictures). Other houses on the street also seem to have a similar setup as they all have these waste pipes coming out of their toilets and dropping into the ground. The toilet itself is connected to a ground floor soil pipe (sub stack?) which isn't connected to the main house soil stack, at least on the ground floor. We are thinking of re-routing the basin waste so it goes into the ground floor soil pipe using one of those toilet pan connectors with a boss / AAV and filling in the hole where the waste pipe was to clean up the look of the house from the outside. Does anyone know where this grey waste pipe goes to (e.g. driveway drain, kitchen sink drain, the ground floor soil pipe)? Could it even be a soakaway? If we do change the basin waste to flow / discharge indoors, is there a good way of capping / filling in the outdoor bit of the grey waste pipe? My worry is if I just yank the pipe out of the ground then gravel and soil from the front garden will clog up the sewer or drain it is/was connected to. On filling up the hole in the interior wall - I've read about using sand and cement alone, sand and cement with galvanised steel mesh or coring out a concrete block and using mortar. Does anyone have any suggestions / preferences? Is bonding plaster a big no-no? Hope that all made sense and thanks for your thoughts.