Tell us about your plot or new build — we match you with up to 3 verified UK specialists so you can compare quotes and choose. Survey-led, compliance-backed, covering England, Scotland, Wales and Northern Ireland.
Sized correctly from day one, building regs included
If your property has no existing off-mains drainage, or you are creating a new dwelling on an off-mains plot, you need a first-time system. All six situations below are handled by our specialist network.
Planning permission granted for a new dwelling where no mains sewer is available. System sizing is based on bedroom count; designed into the build programme from the foundation stage.
Permitted development or full planning to convert an agricultural building to residential. The new dwelling needs its own compliant drainage — usually a sewage treatment plant where land allows.
Self-build projects on green belt or rural land are almost always off-mains. Getting the drainage specification right at the planning stage avoids costly redesigns during the build.
Splitting a large plot into two or more dwellings, or adding an independent annexe, requires separate drainage for each unit. The existing system is almost never large enough to share.
New holiday accommodation units on agricultural or rural land typically require planning consent and a compliant sewage system sized for peak seasonal occupancy, not just winter use.
Small commercial premises — workshops, farm shops, equestrian centres, camping facilities — built in locations without sewer access need a commercial-rated system from day one.
New installations follow a survey-led sequence. Getting the drainage specification right at the start prevents costly amendments once groundworks are under way.
A 5-minute qualifying call: plot location, build programme, number of bedrooms/occupants, ground conditions if known, planning status and timeline.
A specialist visits the plot. Reviews soil type, groundwater level, watercourse proximity, available area for drainage field, access routes and any planning conditions affecting drainage.
A soil porosity test determines whether a drainage field is viable and, if so, how large it must be. Skipped only where a sewage treatment plant with direct discharge to a watercourse is the only viable option.
Fixed written quote covering tank or plant type, capacity, groundworks, electrical (if STP), pipework layout, building regs fees, commissioning and handover documentation.
Building regulations notification is mandatory for new installations. Environment Agency permit is required where a sewage treatment plant discharges to a watercourse. Your specialist handles both.
Groundworks, tank or plant placement, pipework, drainage field construction, electrical connection, backfill and site reinstatement. Typical domestic install: 3–5 working days on site.
Building regs sign-off, commissioning report, operation & maintenance manual, manufacturer warranty documentation and a recommended maintenance schedule.
Site conditions and Environment Agency rules determine which system is installed. Your surveyor confirms the right option after the percolation test.
System capacity is calculated from the number of bedrooms (which determines maximum occupancy). This is a planning guide — your surveyor confirms the final specification on site.
Minimum tank size calculated per BS EN 12566-1 formula: (180 x P x 1.5) + 2000 litres, where P = number of people. Drainage field area based on soil percolation value 12–100 s/mm.
New off-mains drainage systems touch building regulations, planning conditions and in some cases Environment Agency permits. All three are handled by the specialists in our network.
All new foul drainage systems require a building regulations notification and sign-off. Your specialist submits this and obtains the completion certificate as part of the project.
Most domestic systems on new build plots fall under permitted development and do not need separate planning permission for the drainage alone. Your build's planning consent typically covers it — your specialist confirms.
If your sewage treatment plant discharges treated effluent directly to a watercourse (ditch, stream or river), an Environment Agency environmental permit is required. This is handled by your installer and takes 2–6 weeks.
Quick form — 4 steps. Matched with a verified UK specialist within 1 working day.
