Building Regulations Part H

Part H of the UK Building Regulations deals with drainage and waste disposal. This includes the management and disposal of foul water, surface water, rainwater, and solid waste (like from bins and cesspools). It ensures systems are designed and installed in a way that avoids health hazards and environmental pollution.

📘 Part H - Drainage and Waste Disposal

H1 – Foul Water Drainage

Buildings must have adequate drainage systems to carry foul water (sewage, bathroom/kitchen waste) to:

A public sewer (where possible)

A private sewer or treatment plant

A septic tank or cesspool (if above options aren’t feasible)

Pipes must be accessible for maintenance and properly ventilated.

H2 – Wastewater Treatment Systems and Cesspools

Where mains drainage isn't available, properties can use:

Septic tanks

Package treatment plants

Cesspools

These must be:

Of adequate capacity

Located safely (e.g. away from buildings and water sources)

Maintained regularly

H3 – Rainwater Drainage

Roofs and paved areas must have adequate drainage for rainwater.

Options include:

Soakaways

Surface water drains

Combined or separate systems

Systems must avoid flooding or environmental damage.

H4 – Building Over Sewers

Rules apply if building over or near a public sewer.

Must have approval from local water authority (Build Over Agreement).

Ensure no interference with sewer access or structure.

H5 – Separate Systems of Drainage

Where feasible, buildings should have separate systems for:

Foul water

Surface water

Prevents overloading treatment systems and pollution of watercourses.

H6 – Solid Waste Storage

Requires suitable space and access for storing household refuse (bins, recycling).

Should consider:

Distance from dwellings

Odour control

Accessibility for collection

✅ Key Requirements

All drainage systems must:

Be watertight and durable

Prevent smells, blockages, and leaks

Allow cleaning and maintenance

Be adequately ventilated

Must comply with British Standards (e.g. BS EN 12056, BS 6297).

🛑 Minimum Separation Distances (UK Guidance)

✅ From Buildings:

Septic tanks and small sewage treatment plants should be at least 7 metres from any habitable building.

Drainage fields (soakaways) must be at least 10 metres from any building.

✅ From Water Sources:

10 metres from any watercourse (e.g. stream, ditch, river).

50 metres (minimum) from a borehole, well, or spring used for drinking water.

📘 Additional Rules:

🔧 Soakaway (Drainage Field) Design:

Must follow BS 6297:2007+A1:2008.

Should be located:

2 metres from a boundary.

15 metres from a building in clay soils or poorly draining areas (good practice, not legal minimum).

🧾 Environmental Permitting:

If your discharge goes to the ground (via soakaway), you must meet the General Binding Rules — or get a permit from the Environment Agency if:

You're within 50 metres of a drinking water source.

Discharging more than 2 cubic metres (2,000 litres) per day.

📍 Summary Table