Coverage: all of Haringey — N4, N6, N8, N10, N11, N15, N17 and N22, including the Green Lanes restaurant strip, Wood Green, Tottenham High Road, Crouch End and Muswell Hill.

What this covers: plumbing for offices, shops, restaurants, cafés, pubs, salons, gyms and let properties — reactive repairs and planned maintenance, fit-outs, grease management for food premises, backflow protection, water hygiene and legionella, and commercial gas work.

Not a commercial job? A home repair is covered on the domestic pages — Emergency Plumber, Blocked Drains, Boiler Repair and the rest. If you smell gas at the premises, call the National Gas Emergency Service first.

Landlord or managing agent? Commercial repair responsibilities are set by the lease rather than the domestic rules, but the safety and water-hygiene duties below still fall on whoever controls the premises.

Costs: mostly scope- or contract-based — see what it costs ↓.

Jump to: Grease management · Backflow protection · Water hygiene & legionella · Safety first · By district · What it costs · FAQs

Grease management for food premises

For restaurants, cafés, pubs and takeaways, fat, oil and grease (FOG) is the defining plumbing problem. Poured or washed away warm, it sets hard in the drains and causes the blockages and “fatbergs” that flood premises and sewers. It’s also a legal matter: under section 111 of the Water Industry Act 1991 it’s a criminal offence to discharge into a public sewer anything likely to injure it or interfere with the free flow of its contents, and FOG falls squarely within that.² Thames Water is clear that discharging FOG to the sewer is illegal, that food businesses are responsible for disposing of it properly, and that it can recover the cost of clearing blockages — and it has prosecuted businesses that failed to.³ In practice that means a properly sized grease trap or separator, kept serviced — a recurring need along the borough’s busy food strips.

Backflow protection and higher-risk water

Commercial premises often carry a higher contamination risk than a home, so they need stronger backflow protection to stop used or contaminated water being drawn back into the mains. The Water Supply (Water Fittings) Regulations 1999 require a backflow device appropriate to the fluid category of the risk,⁴ and higher-risk settings — some catering, medical, dental, industrial or chemical-dosing uses — can require a reduced-pressure-zone (RPZ) valve. Installing certain backflow arrangements is notifiable to the water company under Regulation 5,⁵ and an RPZ valve needs ongoing testing and maintenance arranged with the water company. A commercial plumber will identify the right category and device for the premises.

Water hygiene and legionella

Any business with a water system must assess legionella risk. Where the assessment identifies a risk that needs control, the HSE’s Approved Code of Practice L8 expects a written control scheme, suitable records, and a competent responsible person to manage it — the duties arising under the Health and Safety at Work etc. Act 1974 and the Control of Substances Hazardous to Health Regulations 2002.⁶ The duty falls on the dutyholder — typically the employer, building owner, landlord or managing agent who controls the water system — and it can’t be contracted away. The risk bites hardest where water sits and warms: stored hot and cold water, showers in gyms and changing rooms, and little-used outlets. A commercial plumber works alongside this, keeping the system designed and maintained so the risk stays controlled.

Safety first

Commercial premises run gas appliances and plant, so the gas rules apply here too.

• Smell gas or suspect a leak? Don’t touch switches or flames, open up if safe, get everyone out, and call the National Gas Emergency Service on 0800 111 999 from outside.¹
• Carbon monoxide. Faulty gas equipment can give off CO — fit audible alarms marked to BS EN 50291 and treat headaches or dizziness that ease when people leave as a warning sign, advises the HSE.⁷
• Commercial gas is Gas Safe — in the right category. Commercial catering equipment and plant need an engineer on the Gas Safe Register for that specific category of work, which is not the same as domestic boiler registration — check both the registration and the categories.⁸

Find a verified commercial plumber by district

Commercial needs follow the trade in each area.

West — Muswell Hill, Highgate, Crouch End, Hornsey, Fortis Green, Alexandra Park. Café, restaurant and salon parades like Crouch End Broadway and Muswell Hill bring grease management and back-of-house plumbing in older buildings, where fitting a grease trap into a period basement kitchen takes some doing.

Centre — Wood Green, Turnpike Lane, Bounds Green, Bowes Park, Noel Park. Wood Green’s shopping centre, offices and high-street units mean shared risers and multi-tenant systems, where one unit’s plumbing problem can reach the businesses around it.

East — Tottenham, Bruce Grove, Seven Sisters, South Tottenham, West Green, St Ann’s. The Green Lanes restaurant strip is the borough’s grease hotspot, so FOG management and trap servicing come up constantly; Tottenham High Road adds retail and light-industrial units.

North-east — Tottenham Hale, Northumberland Park, White Hart Lane, Broadwater Farm. Tottenham Hale’s retail park and the newer commercial and industrial units bring larger systems — bigger water demands, backflow protection and plant that needs scheduled maintenance.

South edge — Harringay/Green Lanes, Finsbury Park, Manor House, Stroud Green. More hospitality along Green Lanes and around Finsbury Park; boundary-sensitive, so confirm the premises is in Haringey.

What commercial plumbing costs

Editorial estimate only — broad indicative ranges to sense-check a quote, not regulated rates, not market data and not a published cost survey. Commercial work is mostly scope- and contract-based, so the premises, the equipment and whether it’s reactive or a maintenance contract move the figure most; always agree the scope and rate first.

A local factor: all of Haringey is inside the London-wide Ultra Low Emission Zone,⁹ and heavier commercial vehicles may also fall under the London-wide Low Emission Zone — worth a word when you book (the Congestion Charge doesn’t reach Haringey).