Correct drainage sizing (main drain 100mm)

Grade or fall at a minimum 1.60 or 1.65% to septic tank

Approved pipe work material used - stamp visible

Correct bedding/side support - 10mm maximum hard stone / blue metal or sparged with 1 part Portland cement and 4 parts clean sand

Vented (between last and second last fixture, <8.5m from the end of drain or >10m from a gully

Gully requirements - at least 150mm below lowest fixture and 75mm above surrounding ground level

Inspection openings (at the point of connection to septic tank, immediately at or upstream of a bend, outside the building where the WC is connected, at interval lengths of <30m where WC are connected)

If back filled, is certifying certificate required from the drainer or plumber

The required cover where applicable comments