Installing a macerating toilet is one of the most practical ways to add a WC or en-suite where conventional drainage is not viable, a basement, loft conversion, or room far from the soil stack. In 2026, expect to pay £600–£1,600 all-in for a standard installation: the macerator unit itself accounts for £300–£800 of that, with the remainder covering a plumber’s labour and any minor electrical work.

The technology grinds and pumps waste horizontally or upward through a small-bore pipe (typically 22–32 mm) to the existing soil stack.1 Because no major structural drainage work is required, installation is far quicker and cheaper than breaking out floors for conventional gravity drainage, but there are important planning and Building Regulations considerations that not every homeowner is aware of.

Cost Breakdown

ItemTypical Cost (2026)
Entry-level macerator unit£300–£450
Mid-range macerator unit£450–£650
Premium / multi-appliance unit£650–£800+
Plumber day rate (installation)£250–£4002
Electrician (if new spur needed)£100–£200
Minor pipe runs / fittings£50–£150
Total (typical mid-range job)£750–£1,400

Prices include VAT at 20%. The mid-range total adds a £450–£650 unit, £250–£400 of plumbing labour and £50–£150 of pipe and fittings, plus £100–£200 for an electrician only where a new spur is needed. Labour rates are typical national figures; London rates run higher (see below).

What Drives the Price

Unit specification. Entry-level units handle a toilet only; mid-range units serve a toilet plus one or two additional appliances (basin, shower, bidet). Multi-appliance units for a full en-suite cost more but eliminate the need for multiple pumps.

Discharge distance and height. Every extra metre of horizontal pipe and every metre of vertical lift increases pump workload and may require a more powerful unit. A typical domestic unit such as Saniflo’s Saniplus Up pumps up to 5 m vertically or 100 m horizontally, but confirm the manufacturer’s stated capacity against your specific layout before purchasing.1

Electrical supply. Macerators run on the standard UK mains supply, declared as 230 V, and typically need a fused spur within 1–2 m of the unit.3 If there is no nearby socket, a registered competent person will need to run one, add £100–£200.

Access difficulty. A bathroom in a ground-floor extension is straightforward. A loft conversion with a long pipe run through tight roof spaces adds labour time and cost.

Plumber day rate. A competent plumber will typically install a macerating toilet in four to six hours. Day rates in 2026 run from about £250 in northern England to around £400 or more in London. Some plumbers price the job as a fixed quote; others charge hourly (£45–£75/hr).

Building Regulations: Part H Drainage

Macerating toilets come under Approved Document H (drainage and waste disposal) and Approved Document G (sanitation). Key points:

  • The discharge pipe must connect to the soil stack, a drain, or a sewer, not a surface water drain or soakaway.
  • Pipe runs must be laid to the correct falls where they pass through gravity sections.
  • The macerator must be installed in accordance with the manufacturer’s instructions and with the drainage standards that replaced the withdrawn BS 8301: BS EN 12056 covers sanitary pipework inside the building4 and BS EN 752 the drainage outside it.5
  • Notification: Installing a new toilet is notifiable work. Only replacing a sanitary convenience with one that uses no more water, and without touching underground drainage, escapes notification.6 You can use an installer on a competent person scheme authorised for “toilets, sinks, washbasins, fixed baths, showers or bathrooms in dwellings”, which means APHC, BESCA, Certsure, HETAS or NAPIT, who self-certifies, or submit a Building Regulations application to your local authority, which sets its own fee.7

Where Macerating Toilets Are: and Are Not, Permitted

Macerators are suitable for:

  • Secondary WCs, en-suites, and cloakrooms where gravity drainage would require expensive groundworks
  • Loft conversions and basement rooms
  • Outbuildings and garages converted to habitable use

They are not a substitute for the only toilet in a dwelling, and that is a Building Regulations point, not just lender practice. Approved Document G says a WC fitted with a macerator and pump may be connected to small-bore drainage only where there is also access to a WC discharging directly to a gravity system, and the macerator meets BS EN 12050-1.8 Approved Document H covers the pump itself: where gravity drainage is impracticable a pumping installation will be needed, a package unit inside a building should conform to BS EN 12050, and it should be designed in accordance with BS EN 12056-4.9 If your property has one WC served by a macerator and nothing else, expect building control to question it, and expect it to be raised during a property sale or mortgage survey. Always check with your local authority or a RICS surveyor if in doubt.

Social housing, listed buildings, and certain commercial premises may have additional restrictions, confirm before purchasing.

Worked Example: Loft En-Suite

A homeowner converts a loft in a Victorian terrace in Bristol. They want a small en-suite with a WC and basin. The soil stack is three floors below and 8 m away horizontally.

ItemCost
Mid-range multi-appliance macerator£580
Plumber (6 hrs @ £55/hr)£330
Electrician (new fused spur)£140
Pipe, fittings, fixings£90
Building Regulations (competent person scheme)included in plumber’s cert
Total£1,140

Compared with cutting through three floors of Victorian joinery for conventional drainage, this saves several thousand pounds.

DIY Considerations

Fitting the WC pan and cistern is within the reach of a competent DIYer. However, the small-bore discharge pipework and the electrical spur must be handled correctly:

  • Plumbing: Adding a new WC is notifiable building work even when you do it yourself, and any work connecting to the soil stack or foul drain is best left to a professional to ensure correct fall, sealing, and access for rodding.
  • Electrical: Spurring off an existing circuit is not notifiable in England unless it falls in a special location, which Approved Document P defines as within the room containing the bath or shower, from floor level to 2.25 m and within 0.6 m of the bath or shower tray, or within 1.2 m of the shower head centre where there is no tray.10 A new circuit for the unit is notifiable. Either way the work is best carried out by a qualified electrician or registered competent person.

Attempting a full DIY installation without the relevant qualifications risks voiding the unit warranty, failing a Building Regulations inspection, and creating problems at resale.

Ongoing Costs and Maintenance

Macerators are electro-mechanical and will eventually require servicing or replacement. Budget accordingly:

  • Descaling: In hard-water areas, Saniflo recommends its own descaler every three to six months (£10–£20 a bottle).11 Small amounts of bleach or disinfectant are fine for routine cleaning, but avoid strong drain cleaners.11
  • Seal replacement: Rubber seals and valves wear over time and may need replacing within the unit’s life. A plumber can replace seals for £150–£250 in parts and labour.
  • Full unit replacement: Saniflo designs its units to give 8 to 10 years of reliable service with proper installation and maintenance, and some last much longer.11 Allow the price of a new unit (£450–£650 for a mid-range model) plus up to a day’s plumbing labour (£250–£400).
  • Running costs: A unit such as the Saniplus Up has a 400 W motor that runs for a few seconds per flush, so the annual electricity cost is negligible.1

Choosing an Installer

Look for a plumber registered with a competent person scheme authorised for sanitary appliances: APHC (Association of Plumbing and Heating Contractors), BESCA, Certsure, HETAS or NAPIT. Those schemes allow self-certification of Building Regulations notifiable work.7 CIPHE (Chartered Institute of Plumbing and Heating Engineering) is a professional institute rather than a competent person scheme, so CIPHE registration is a useful mark of competence but does not by itself let a plumber self-certify. Get at least two fixed-price quotes and confirm they cover: unit supply, installation, pipe runs, electrical coordination, and Building Regulations sign-off.

The rules in this note are those that apply in England. Scotland, Wales and Northern Ireland have their own building standards and permitted development rights.

References (11)

Figures in this note were checked against the sources below on 30 September 2026. Superscript numbers in the text point to them. Every source the site cites, by topic.

  1. 1technicalsupplier figureSFA Saniflo, guidance.RN-DNBJ01Saniflo product page for the Saniplus Up macerator; it states the unit discharges through 22, 28 or 32 mm small-bore pipework.
  2. 2costvery strongOffice for National Statistics.RN-MMT1DOA price, true at 2026-01. The ASHE Table 14 dataset gives annual estimates of paid hours worked and earnings for UK employees by sex and by full-time or part-time status, broken down to four-digit Standard Occupational Classification, which is the level that isolates individual construction trades such as bricklayers, carpenters, plasterers and electricians. Released 23 October 2025 as the 2025 provisional edition (zip, about 10.7 MB), with revised and provisional editions back to 2017. A correction dated 19 December 2025 suppressed annual pay estimates for SOC 3312 police officers in some areas; construction occupations are unaffected.
  3. 3technicalvery strongThe National Archives (legislation.gov.uk), legislation.RN-16LK2TSets the declared characteristics of the UK public supply. Declared frequency is 50 Hz. For a low voltage supply the declared voltage is 230 volts between phase and neutral conductors at the supply terminals. Permitted variations are 1 per cent above or below the declared frequency; for low voltage, a variation not exceeding 10 per cent above or 6 per cent below the declared voltage; for high voltage below 132 kV, 6 per cent either way; at or above 132 kV, 10 per cent either way. This is the authority for correcting '240 V' in appliance and electrical copy: 240 V has not been the declared nominal voltage since harmonisation, though it sits inside the +10% tolerance.
  4. 4technicalstrongBSI Knowledge, a standard.RN-0BO72HPublished 15 September 2000 and current. This is the standard behind soil and waste pipe sizing and layout inside a house, and the document that replaced the withdrawn BS 5572 code of practice for sanitary pipework on the same date. It applies to wastewater drainage systems operating under gravity in dwellings and in commercial, institutional and industrial buildings, and sets out the principles to be followed for both layout and calculation of sanitary pipework, with only limited provisions for trade effluent and pumped fluids. It sits alongside BS EN 12056-1 for general and performance requirements, -3 for roof drainage, -4 for wastewater lifting plants and -5 for installation, testing and maintenance. Cite it, with Approved Document H, when a note gives soil stack or branch waste pipe diameters, trap seal depths or branch gradients.
  5. 5technicalstrongBSI (British Standards Institution), a standard.RN-BCH6ZHBS EN 752:2017, drain and sewer systems outside buildings, sewer system management. Sets the objectives and performance requirements for drainage outside the building line, which is the part of a drainage run that becomes the water company's or a shared responsibility rather than the householder's alone.
  6. 6technicalvery strongThe National Archives (legislation.gov.uk), legislation.RN-HUA3K9Lists the building work that is not notifiable. Paragraph 1(j) is the sanitary one: replacing a sanitary convenience with one that uses no more water than the one it replaces, a washbasin, sink or bidet, a fixed bath, a shower, a rainwater gutter or a rainwater downpipe, in each case where the work does not include any work to underground drainage. Installing a new WC, as opposed to replacing one, therefore stays notifiable, and so does any replacement that touches underground drainage or uses more water. The Schedule also covers replacement of non-structural windows in certain circumstances and various electrical and heating replacements, all subject to the work not prejudicing health or safety.
  7. 7technicalvery strongMinistry of Housing, Communities and Local Government.RN-SAMO3MThe official list of competent person schemes whose members can self-certify certain building work instead of getting building regulations approval, published 4 April 2013 and last updated 12 March 2018. Named schemes with contact numbers include ATTMA, APHC, Assure Certification, Blue Flame Certification, the British Board of Agrement, BESCA, Capita Gas Registration and Ancillary Services trading as Gas Safe Register, CIGA, Certass, Certsure LLP trading as NICEIC, the Elmhurst Airtightness Scheme, Fensa Limited, HETAS Limited, NAPIT Registration Limited, the National Federation of Roofing Contractors trading as CompetentRoofer, and OFTEC. Two footnotes matter: the Gas Safe Register is not technically a competent person scheme although in practice its installers carry the same building regulations responsibilities, and Benchmark Certification Limited ceased to operate as a competent person scheme on 10 February 2017, becoming part of NAPIT Registration Limited that day. Installers joining an electrical scheme are added to the single electrical competent person register.
  8. 8technicalvery strongMinistry of Housing, Communities and Local Government.RN-YAW64MRequirement G3(4) states the hot water supply to any fixed bath must be designed so the water delivered to that bath cannot exceed 48 degrees C; paragraph 3.65 says this is achieved with an in-line blending valve or other temperature control device with a maximum temperature stop, and 3.66 accepts valves to BS EN 1111:1999 or BS EN 1287:1999 that fail safe. G3(3) requires unvented storage vessels to prevent stored water exceeding 100 degrees C and to convey safety discharge somewhere visible and safe. Regulation 36 and Requirement G2 cap potential consumption in a new dwelling at 125 litres per person per day, or the optional 110 litres per person per day where a planning condition specifies it; G2 applies only to dwellings erected or formed by material change of use. Sections G4 sanitary conveniences, G5 bathrooms and G6 food preparation areas set scale of provision.
  9. 9technicalvery strongMinistry of Housing, Communities and Local Government.RN-SM6TRWThe statutory source for soakaway design and the discharge hierarchy every garden drainage note should state. Requirement H3(3) lists the order of priority for rainwater discharge: (a) an adequate soakaway or other adequate infiltration system, or where not reasonably practicable (b) a watercourse, or where not reasonably practicable (c) a sewer. Paragraph 3.25 bars infiltration devices within 5 metres of a building or road, in ground where the water table reaches the bottom of the device at any time of year, too close to other drainage fields or soakaways, or where contamination could pollute groundwater. Paragraph 3.26: soakaways serving less than 100 square metres are generally square or circular pits filled with rubble or lined with dry-jointed masonry or perforated ring units. Paragraph 3.27: design to a return period of once in ten years, and for small soakaways serving 25 square metres or less a design rainfall of 10mm in 5 minutes may be assumed as the worst case. Paragraph 3.28 requires percolation tests to derive the infiltration rate, and paragraph 3.30 sends larger soakaways to BS EN 752-4 or BRE Digest 365 Soakaway design. Paragraphs 2.10 to 2.12 cover pervious paving over a granular storage reservoir and warn against its use where sediment or oil spillage would block the pores. For foul drainage, paragraph 2.33 sets a minimum 75mm internal diameter, or 100mm for a WC, and Table 6 gives minimum gradients of 1 in 40 for 75mm and 100mm at peak flows under 1 litre per second.
  10. 10technicalvery strongMinistry of Housing, Communities and Local Government.RN-JYJ3I5The document that decides what electrical work a homeowner may legally do themselves, and the exact list of notifiable jobs. Regulation 12(6A), reproduced at paragraph 2.5, makes only three things notifiable: the installation of a new circuit, the replacement of a consumer unit, and any addition or alteration to existing circuits in a special location. Regulation 12(9) defines special location as, in a room containing a bath or shower, the zone extending vertically from finished floor level to 2.25 metres (or the shower head position if higher) and horizontally 600mm from the edge of the bath tub or shower tray. Paragraph 2.7 states that all other electrical installation work is not notifiable, namely additions and alterations to existing installations outside special locations, and replacements, repairs and maintenance anywhere. Paragraph 2.8 gives worked examples: a built-in cooker is not notifiable unless a new cooker circuit is needed, and connecting an electric gate or garage door to an existing isolator is not notifiable but running a new circuit from the consumer unit to that isolator is. Paragraph 2.2 confirms Part P reaches outdoor work including fixed garden lighting, pond pumps and outbuildings such as sheds, detached garages and domestic greenhouses. Notifiable work must be certified by self-certification by a registered competent person, third-party certification, or a building control body (paragraph 3.1), with the compliance certificate issued within 30 days (paragraph 3.4). Note that Approved Document P is a source of guidance rather than a ban: non-notifiable work still has to comply with BS 7671.
  11. 11technicalsupplier figureSFA Saniflo, guidance.RN-VYPFOISaniflo's own FAQ for UK customers; it recommends its descaler every three to six months in hard-water areas.

  1. Saniplus UP: macerator with 4 inlets, SFA Saniflo, accessed 30 September 2026. saniflo.co.uk

  2. ASHE Table 14.6a, hourly pay excluding overtime by occupation, 2025 provisional, Office for National Statistics, accessed 21 September 2026. Priced at 2026-01, so no calibration is needed. ons.gov.uk

  3. The Electricity Safety, Quality and Continuity Regulations 2002, regulation 27: declaration of phases, frequency and voltage, legislation.gov.uk, accessed 10 September 2026. legislation.gov.uk

  4. BS EN 12056-2:2000 Gravity drainage systems inside buildings. Sanitary pipework, layout and calculation, BSI, accessed 10 September 2026. knowledge.bsigroup.com

  5. BS EN 752:2017 Drain and sewer systems outside buildings. Sewer system management, BSI, accessed 10 September 2026. knowledge.bsigroup.com

  6. The Building Regulations 2010, Schedule 4: descriptions of work where no building notice or deposit of full plans required, legislation.gov.uk, accessed 10 September 2026. legislation.gov.uk

  7. Competent person scheme: current schemes and how schemes are authorised, Ministry of Housing, Communities and Local Government (GOV.UK), accessed 10 September 2026. gov.uk

  8. Approved Document G, Sanitation, hot water safety and water efficiency, 2015 edition incorporating 2016 and 2024 amendments, Ministry of Housing, Communities and Local Government, accessed 30 September 2026. assets.publishing.service.gov.uk

  9. Approved Document H, Drainage and waste disposal, 2015 edition, Ministry of Housing, Communities and Local Government, accessed 10 September 2026. assets.publishing.service.gov.uk

  10. Approved Document P, Electrical safety, Dwellings, 2013 edition, Ministry of Housing, Communities and Local Government, accessed 10 September 2026. assets.publishing.service.gov.uk

  11. FAQ, SFA Saniflo, accessed 30 September 2026. saniflo.co.uk