Fixington

Greywater System

Trade: Plumber

⭐ Introduction

A greywater system is a plumbing setup that collects used water from your bath, shower, washbasin, or washing machine, and then filters and redirects it for non-potable uses — such as flushing toilets or garden irrigation. Unlike blackwater, which comes from toilets and contains harmful bacteria, greywater is less contaminated, making it more straightforward to recycle on-site.

Installing a greywater system can help reduce your household water consumption, lower water bills, and ease strain on local drainage and sewage systems. It’s especially useful in areas facing water shortages or for homeowners keen to live more sustainably.

If you’ve noticed high water bills or are planning an eco-friendly home improvement, a plumber specialising in greywater systems can advise if it’s right for your property.

🔧 What the job involves

Fitting a greywater system typically includes:

  • Installing collection points: Plumbing modifications to divert wastewater from baths, showers, and sometimes washing machines to a dedicated tank or filtering system.

  • Filtering and treatment: Greywater is filtered to remove hair, lint, soap residues, and other solids. Some systems use simple filters, while more advanced ones may include biological treatment to reduce bacteria.

  • Storage: A holding tank stores treated greywater before it’s pumped to where it’s reused, like toilet cisterns or outdoor taps.

  • Distribution: Additional pipework and sometimes pumps send the treated greywater to appliances and outdoors.

  • Controls and safety: Systems include backflow prevention devices to stop greywater contaminating your clean water supply, and may have alarms or sensors to avoid overflows.

All installations must meet UK Building Regulations Part G, which deals with sanitation, hot water safety, and water efficiency. It’s important the system prevents any health risk and doesn’t interfere with your mains water or drainage.

📝 Step-by-step from booking to completion

  1. Initial enquiry: Contact a reputable plumber specialising in greywater systems. Provide details about your property, current plumbing, and what you want to achieve.

  2. Site survey: The plumber visits to inspect your property’s drainage layout, water use, and space for tanks or filter units. They assess feasibility and advise on options.

  3. Quote and plan: You receive a detailed written quotation outlining costs, timelines, and materials plus necessary consents, if any.

  4. Booking and preparation: Agree a date for installation and prepare access to plumbing and installation areas.

  5. Installation day: The plumber disconnects appropriate wastewater lines and installs filter units, tanks, new pipework, pumps, and safety devices. They test the whole system thoroughly.

  6. Commissioning and advice: The plumber demonstrates how the system works, explains maintenance tasks, and provides all paperwork, including any Part G compliance documentation.

  7. Aftercare: Arrange routine servicing to keep filters and pumps working efficiently and check for leaks or contamination risks.

💷 Main costs to expect

  • Labour: Most of the cost; includes plumbing modifications, installation of tanks/filters, pipework, and commissioning. Typically £500–£1500.

  • Materials & parts: Tanks, filters, pumps, valves, backflow preventers. These can range from £300–£1000 depending on system size/complexity.

  • Additional works: Extra pipework, electrical connections, or drainage upgrades may be required (£100–£500).

  • Disposal: Removal of old plumbing parts or excavated soil, if relevant (£50–£150).

  • Certification: Compliance paperwork or building control notifications may have minor administrative fees (variable).

Example: A basic bathroom greywater system might cost around £1200 total (£800 labour + £350 parts + £50 disposal).

📊 What affects the price

  • Property size and layout complexity

  • Number and types of water sources connected

  • Accessibility for plumbing work in walls or underfloor

  • Need for electrical work (pumps or sensors)

  • Required Building Regulations compliance and monitoring

  • Remedial works if existing plumbing is unsuitable or damaged

  • Location (labour costs vary across the UK)

  • Urgency or timing (weekend or emergency work can cost more)

⏱ How long does it take?

  • Simple retrofit (e.g. connecting bath/shower waste to a small 150L tank): 1–2 days

  • New installations with multiple sources, filtration, pumps, and garden irrigation: 3–5 days

  • Large, complex systems integrated with central heating or smart controls can take over a week.

Your plumber will give a realistic timeframe after their survey.

🏠 Can you DIY it?

Installing a greywater system is not a typical DIY project. It requires:

  • A good understanding of plumbing, drainage, and water safety requirements

  • Proper installation of backflow prevention devices to stop cross-contamination

  • Compliance with UK Building Regulations Part G

  • Sometimes, electrical work for pumps and sensors (must be done by a qualified electrician)

An incorrectly installed system risks health hazards, potential fines, and invalidates insurance policies. For these reasons, it’s best left to experienced plumbers.

💰 Typical UK price range

Most domestic greywater system installations cost roughly £1000 to £3000 including parts, labour, and VAT at 20%. This is a general estimate; your quoted price may vary.

Keep in mind:

  • VAT is usually charged on materials and labour, unless carried out by a VAT-registered business.

  • Grants or local authority incentives for water-saving systems can sometimes offset costs.

✅ Handy tips before you start

  • Check your property’s existing plumbing layout; obtaining a plan beforehand can speed surveys.

  • Ensure clear access to installation areas; clearing cupboards or garden space helps.

  • Ask for a written quotation that includes compliance with Building Regulations Part G.

  • Understand ongoing maintenance: regular cleaning of filters and periodic pump servicing keep the system safe and efficient.

  • Keep all paperwork, including installation certificates and maintenance guides.

  • Discuss with your plumber any concerns about water quality or potential impact on appliances.

  • Consider your greywater reuse preferences early—whether for toilets only, garden watering, or both.

By planning carefully and using a qualified plumber, you can enjoy the benefits of reduced water bills and a greener home with confidence.