Running a café, restaurant, office, shop, salon or other business premises in Havering and need a plumber who understands the commercial duties? This page connects you with verified, insured plumbers across Havering who work on non-domestic premises, from Romford and Hornchurch to Upminster and Rainham.

✅ Checked before listing — identity, insurance, trading presence, Gas Safe (where relevant).
How we verify →
✅ Workmanship guarantee badges on listings — 1, 3, 6 or 12 months

Commercial work ranges from a single repair to a fit-out, and duties vary by premises type, so scope, access and out-of-hours needs are all worth confirming with the plumber before booking.

→ Find a verified Havering commercial plumber — see the verified list below.

Coverage: RM1, RM2, RM3, RM4, RM5, RM6, RM7, RM11, RM12, RM13, RM14 — Romford, Gidea Park, Collier Row, Harold Hill, Harold Wood, Hornchurch, Elm Park, Upminster, Cranham, Rainham, South Hornchurch and the rural-edge villages.
Commercial plumbing covered: repairs, maintenance and installation for non-domestic premises — commercial kitchens and washrooms, grease management, backflow protection (including RPZ valves), water heaters and hot-water systems, leak repairs and pipework, taps, cisterns and urinals, thermostatic mixing valves (TMVs), water efficiency and sub-metering, and fit-out plumbing. For commercial plumbing in Havering, use the verified list above.
Different job? Domestic plumbing → the relevant Havering service page; a blocked commercial drain → Blocked Drains; a leak you can’t locate → Leak Detection. Commercial gas work (catering appliances, commercial boilers) needs an engineer on the commercial Gas Safe categories — separate from domestic — so confirm the right registration before booking gas work.
Costs: commercial work is quoted per job; see What it costs ↓ for why.

Jump to: What commercial plumbing covers ↓ · Grease, FOG & commercial kitchens ↓ · Backflow & higher-risk premises ↓ · Trade effluent & water efficiency ↓ · By premises type ↓ · What it costs ↓ · FAQs ↓

What commercial plumbing covers

Commercial plumbing is domestic plumbing with the duties turned up — more demand on the system, more people relying on it, and a layer of regulation that doesn’t apply to a house. The common work:

• Commercial kitchens — high-use sinks, dishwashers and glass-washers, grease management, and the supply and waste to take the volume (more below).
• Washrooms — banks of basins, WCs and urinals, often with sensor taps, auto-flush controls and thermostatic mixing valves (TMVs) to control scald risk where the public or vulnerable people use them.
• Hot water at scale — commercial water heaters, cylinders and circulation, sized for demand rather than a single household.
• Backflow protection — commercial premises are usually a higher contamination-risk category than a home, so the protection steps up (more below).
• Leaks, pipework and maintenance — including the planned, out-of-hours work businesses often need to avoid disrupting trading.
• Fit-out plumbing — the first-fix and second-fix for a new unit, a change of use, or a refurbishment.

The thread through all of it is that a business carries duties — to staff, customers, its water company and its insurer — that a homeowner doesn’t, so “verified and insured” matters more here, not less.

Grease, FOG and commercial kitchens

If you run a food business, fat, oil and grease (FOG) is the issue that causes the most blocked drains and the most grief. Poured down a sink, FOG cools and hardens in the pipework and sewer, building up until it blocks — and a commercial kitchen produces far more of it than a home. Thames Water, the sewerage company for most of Havering, is clear that fats, oils and grease should be kept out of the drains rather than washed down them.¹

In practice that means a food business usually needs a grease trap or grease interceptor on the kitchen waste, sized to the kitchen’s output, plus good practice — scraping plates, not pouring oil down the sink, and keeping the trap maintained. A common failure a plumber sees is a grease trap that was right for the business when it opened but is now undersized because the business has grown — so it’s worth reviewing if your kitchen’s gotten busier. A verified commercial plumber can advise on the right trap, fit it, and set up a maintenance routine — far cheaper than the blockage, the bad smell, and the closed kitchen that follow when FOG wins.

Backflow and higher-risk premises

Backflow — water being drawn back into the supply — is a bigger deal commercially than domestically, because business premises often handle fluids that are a higher contamination risk. Water Regs UK sets out that backflow protection must be matched to the highest applicable fluid-category risk downstream, and commercial fittings and processes frequently sit at a higher category than the equivalent in a home.²

What that means on the ground:

• Fluid Category 4 risks (a significant health hazard — for example chemical dosing, some commercial processes) typically need an RPZ valve (reduced pressure zone assembly), which is a notifiable, type-tested device that has to be commissioned and tested by an accredited tester, then re-tested periodically.³
• Fluid Category 5 risks (a serious health hazard — food production, healthcare, anything in contact with waste) need physical separation: an air gap, typically a Type AA or AB arrangement such as a break tank, not a mechanical valve.
• Even routine fittings shift up: a commercial hose-union tap, a catering dishwasher or a non-domestic sink is generally treated as a higher category than the domestic equivalent.

The Regulations require every system to carry adequate backflow protection appropriate to the risk,⁴ so a verified commercial plumber assesses the fluid category for each point of use and fits protection to match — and, for an RPZ, arranges the accredited testing the device needs.

Trade effluent and water efficiency

Two more commercial-only considerations worth knowing.

Trade effluent consent. If your business discharges trade effluent — liquid waste from an industrial or commercial process, such as vehicle washing, laundry, manufacturing or certain treatment processes — to the public sewer, that needs the sewerage company’s consent. Thames Water sets out that a trade effluent consent is a legal document under the Water Industry Act 1991, and it’s an offence to discharge trade effluent without one.⁵ Note this is separate from a food business: an ordinary restaurant’s wastewater isn’t usually classed as trade effluent needing consent — but it does need the grease management covered above. A plumber working on a process-discharge installation can build it to the consent’s conditions; the consent itself is between the business and the water company.

Water efficiency and sub-metering. Businesses pay for water and for the wastewater they return, so reducing waste is a direct saving — fixing dripping taps and leaks, fitting sensor or push taps and low-flush WCs and urinals, and sub-metering different parts of a premises so usage can be tracked. A commercial plumber can audit the obvious losses; on Havering’s hard water, scale on volume hot-water plant is also a quiet efficiency drain worth addressing.

Fittings still have to comply. As in any premises, under Regulation 4 of the Water Supply (Water Fittings) Regulations 1999, water fittings must be of an appropriate quality and standard, with WRAS (or equivalent) approval used as evidence of compliance.⁶

Commercial premises across Havering

Havering’s commercial plumbing reflects its mix of town centres, parades, industrial areas and the hard-water supply. Here’s the local picture.

Romford (RM1, RM2, RM7) — the borough’s main commercial centre, with the shopping centre, the market, restaurants, bars, offices and salons. Food and drink premises here mean a lot of grease management and high-use washrooms, and town-centre units often need out-of-hours work to avoid disrupting trading.

Hornchurch & Elm Park (RM11, RM12) — high-street parades, restaurants and cafés, dental and medical practices, and small offices. Healthcare and food premises are where TMVs (scald control) and higher-category backflow protection come in.

Upminster & Cranham (RM14) — a smaller but established commercial parade, with cafés, shops and professional offices, plus larger premises toward the edges where a fit-out or refurbishment is more common.

Rainham, South Hornchurch & Beam Park (RM13) — this is where Havering’s industrial and trade estates sit, alongside the regenerating Beam Park area. Light-industrial and process premises here are the most likely to involve trade effluent, RPZ-level backflow protection and heavier-duty installations.

Harold Hill, Harold Wood & Collier Row (RM3, RM5) — local parades, the Harold Hill industrial area, and community and care premises. A mix of everyday commercial maintenance and the occasional higher-spec job on a care or food premises.

Gidea Park, Emerson Park & the rural edge (RM2, RM4) — smaller commercial clusters, pubs and restaurants, and some rural-edge premises (farms, equestrian, leisure) where the supply, drainage and backflow risks can be unusual and worth a proper assessment.

If your premises is near the Romford / Barking & Dagenham boundary at Rush Green, confirm the postcode is RM and within Havering before booking.

What it costs

Commercial plumbing is quoted per job, not from a price list — because scope, premises type, access, out-of-hours requirements, and the regulatory work involved (grease traps, RPZ commissioning and testing, backflow assessment) vary far too much for a meaningful range. Any indicative domestic figures elsewhere on this site won’t apply to commercial work.

Havering is outside the central London Congestion Charge zone, but like every Greater London borough it sits inside the London-wide Ultra Low Emission Zone (ULEZ), which the TfL ULEZ scheme operates across all London boroughs (excluding the M25 itself). A non-compliant vehicle may incur the daily charge, so it’s reasonable to ask whether any emissions-zone charge is included in a quote.⁷

When you contact a plumber from this directory, you can ask about availability and out-of-hours work, whether they’re set up for your premises type, whether they hold the right accreditations for the work (for example accredited RPZ testing, or the commercial Gas Safe categories for any gas appliance), and how they quote and invoice — you’re not obliged to proceed until you’ve agreed the scope. VerifiedPlumbers is a directory that connects you with verified plumbers; it doesn’t carry out the work itself.

Frequently asked questions

Related services in Havering

• Blocked Drains in Havering — blocked commercial drains and waste
• Leak Detection in Havering — tracing a leak on commercial premises
• Emergency Plumber in Havering — urgent help that can’t wait for trading hours
• All plumbing services in Havering — the full directory

Related guides

• London Hard Water Guide — scale on commercial hot-water plant
• How to Read a Plumbing Quote — checking a commercial quote
• London Plumbing Costs & Compliance Guide 2026 — how plumbing and compliance work is priced