How to Get Commercial Plumbing and Heating Contracts
The short answer
Commercial plumbing and heating work comes through four doors: landlord gas servicing, plant room and water hygiene maintenance, M&E packages for main contractors, and direct commercial clients. Get the gas categories and paperwork that door needs, then price the contract, not the visit.
- Landlords buy servicing every year. Every rented home with gas needs a safety check every 12 months, so housing associations and managing agents tender it as contracts. Small firms win them.
- Your Gas Safe card limits what you can bid for. Commercial boilers and plant rooms need the commercial core assessment (COCN1, or CODNCO1 from domestic) plus the right categories.
- Water hygiene is recurring work too. HSE guidance says sentinel outlets are checked monthly: hot at least 50°C within a minute, cold below 20°C after two minutes.
- Price per property per year, with response times costed. Out-of-hours cover and remedials are where servicing contracts make or lose money.
Most plumbing and heating firms start domestic: boilers, bathrooms, leaks, landlords with a handful of flats. The step into commercial is where a firm stops living job to job and starts having contracts that pay every month.
The catch is that "commercial plumbing" is four different markets, and each one checks different things before it lets you price. This guide is for owners of UK plumbing and heating businesses who want their first commercial contracts, or more of them. If you want help choosing your route, book a free strategy call.
Four doors into commercial plumbing and heating
| Route | Who buys | Typical work | What wins it |
|---|---|---|---|
| Landlord gas servicing | Housing associations, councils, block managing agents, large private landlords | Annual gas safety checks, boiler servicing, repairs, out-of-hours cover | Response times, certificates on time, the right gas categories |
| Plant room & water hygiene | Facilities managers, schools, care homes, gyms, offices | Commercial boiler servicing, pressurisation units, calorifiers, legionella monitoring | Commercial gas categories, reliable reporting |
| M&E subcontract packages | Main contractors, fit-out and M&E contractors | Plumbing, drainage, heating and sanitaryware on fit-outs and new builds | Price to the drawings, labour you can supply, clean handover |
| Direct commercial clients | Restaurants, salons, shops, small business owners | Kitchens, washrooms, water heaters, heating upgrades | Quick response, clear quotes |
Pick one as your main route for the next year. Servicing contracts give the steadiest cash; subcontract packages give the biggest single jobs.
Check your Gas Safe card before you bid
Beyond gas, buyers will also ask for RAMS for the actual job, a written health and safety policy and training records. They want public and employer's liability insurance at the level in their questionnaire, and sometimes an SSIP scheme. See which accreditations you need for commercial work.
Your Gas Safe registration covers only the categories on your card. A domestic engineer cannot legally work on a commercial boiler, and buyers check.
The commercial ladder:
- Core commercial assessment. COCN1, or CODNCO1 if you are changing over from the domestic core (CCN1). It is the prerequisite for every other commercial category.
- Appliance categories for the work you will bid for, for example CIGA1 for indirect-fired appliances such as commercial boilers.
- Pipework categories, for example ICPN1 to install commercial pipework and TPCP1 or TPCP1A to test and purge it.
Map the contracts you want against your engineers' cards. If only one engineer holds commercial categories, that person is your capacity limit and your risk.
I made this mistake myself. At Craftex I paid a lot for accreditations, and on their own they never paid off. Get an accreditation only when a specific tender for a specific project asks for that specific accreditation. Most schemes take 2–3 months, so you will have time once the request is real.
Route 1: landlord gas servicing contracts
Every rented home with gas needs a safety check every 12 months by a Gas Safe engineer. The landlord keeps the record for 2 years and gives existing tenants a copy within 28 days. Housing associations and managing agents with hundreds of homes do not book these one by one: they tender them as contracts.
These contracts are winnable by small firms. Here is a real example from Find a Tender. Irwell Valley Housing Association tendered gas servicing and repairs for communal heating and hot water. It covered about 27 residential schemes and commercial properties.
The scope included annual gas safety checks, commercial boiler servicing, HIU maintenance and out-of-hours cover 365 days a year. The contract was worth £85,000 including VAT over roughly 2 years and 8 months. Eleven firms bid, and it went to an SME from Wigan.
What that tells you:
- Contracts are often modest in size, which keeps big national firms less interested and leaves room for you.
- Out-of-hours cover is not optional. If you cannot run a rota, partner with another firm or don't bid.
- The questions are predictable: response times, first-time fix, how you manage no-access visits, how certificates reach the client, and who your engineers are.
Where to find them: set free alerts on Find a Tender and Contracts Finder for "gas servicing", "heating maintenance" and "landlord gas safety". For private blocks, approach managing agents directly. Our guides on council contracts and frameworks cover the tender side.
Want help choosing which servicing contracts to bid for and pricing them so they pay?
Book a free call.
Price the contract, not the visit
Servicing contracts lose money in the hours nobody priced: travel between properties, no-access visits, paperwork and the out-of-hours phone.
Worked example: annual servicing for 180 flats (example figures)
| Line | Basis | £ a year |
|---|---|---|
| Checks and services | 180 × 1.25 h × £30 true hourly cost | 6,750 |
| No-access revisits | 15% of properties × 1 h × £30 | 810 |
| Certificates and admin | 180 × 0.25 h × £30 | 1,350 |
| Out-of-hours rota share | Your rota cost ÷ properties covered | 2,400 |
| Direct cost | 11,310 | |
| Price at a 30% margin floor (÷ 0.70) | 16,157 (≈ £90 per flat) |
Price only the visit and you would quote around £54 per flat. The difference is the no-access visits, paperwork and the rota, and it decides whether the contract pays.
Two rules for every servicing contract:
- Remedials are quoted, not assumed. Agree in writing who approves spend and the limit an engineer can fix on the spot. Price them from hours, as in how to price plumbing jobs.
- Measure first-time fix and no-access rates monthly. They are the numbers clients score you on at renewal, and the numbers that move your margin.
For margin on boilers, call-outs and heat pumps, see our plumbing business profit margin guide.
Route 2: plant rooms and water hygiene
Offices, schools, care homes, gyms and hotels have plant rooms that need servicing whether or not anything breaks. Facilities managers buy this as planned maintenance, with reactive call-outs on top.
Water hygiene is a natural add-on. HSE guidance for controlling legionella in hot and cold water systems includes:
- monthly temperature checks at sentinel outlets: hot at least 50°C within one minute, cold below 20°C after two minutes
- calorifier outgoing water at 60°C or above
- cold water tank temperature checked every 6 months
- showerheads cleaned and descaled quarterly (or as the risk assessment says)
- infrequently used outlets flushed weekly
Someone has to do and record these checks on every site. If your engineers are already in the plant room for servicing, offering monitoring as part of one contract makes you harder to replace. Get proper training before you sell it.
Route 3: plumbing and heating packages for main contractors
Main contractors need plumbing, drainage, heating and sanitaryware on almost every fit-out, refurbishment and new build. Their common complaint: subcontractors who price low, then cannot supply the labour, or finish without the commissioning sheets and O&M information.
- List 20–30 main contractors and fit-out firms within an hour of you.
- Call the estimator or commercial manager and ask what they are missing from their current plumbing subcontractors.
- Send a one-page capability sheet: team, gas categories, recent commercial jobs with photos, insurance. (Still a small team? See how to grow a plumbing business first.)
- Price one small package, and deliver the paperwork on completion day.
More on this route: how to get subcontract work from main contractors.
Before you sign, set up the commercial cash basics. Submit applications for payment on the contract dates. Have a process for pay less notices. Track retention job by job (retention not released?). Sort your CIS status. Know the VAT domestic reverse charge, under which the contractor accounts for the VAT on your work.
From plumber to his first £50K commercial project
After 20+ years as a plumber, Dmitriy changed how he sells and prices: live quote presentations and a weekly follow-up on every open quote. Individual results, not typical or guaranteed.
Construction Project Leads Guide
Where to find projects before they reach tender, public and private.
Get the free guideRoute 4: direct commercial clients
Restaurants, salons, cafés and small offices need washrooms, kitchen supplies, water heaters and heating upgrades, usually fast and often out of hours. They rarely have a consultant, so they buy from whoever explains the options clearly and shows up when promised.
These jobs are smaller but often turn into maintenance agreements. After every commercial job, offer an annual service visit at a fixed price. Ten small businesses on annual agreements is the start of a maintenance book.
Want to see whether your firm is ready for contracts, and which ones to go after first?
Book a free strategy call.
Your first 90 days
- Weeks 1–2: pick your route. Check every engineer's gas categories against the work you want. Book any changeover assessments.
- Weeks 3–4: update RAMS, H&S policy and insurance. Write a capability sheet with real photos and the number of engineers and vans.
- Weeks 5–8: set tender alerts, call managing agents and main contractors, and ask to price one contract or package.
- Weeks 9–12: deliver it with certificates on time, measure first-time fix and response times, and ask for a reference.
At BizMentor, Sviat Jay works through this one-to-one with plumbing and heating owners. He runs a working construction company, Craftex, that buys plumbing and heating packages. So he knows what clients check, and why most subcontractors never get the second job.
Owners who don't need one-to-one start in a small group with regular one-to-one calls. The aim is results in about 4 months, not 1–3-year programs. To plan your first contracts, book a free strategy call. To see where your business stands first, take the free 4-minute Construction Business Scorecard.
Regulatory and tax points are general information as of October 2026, for England. Check details with Gas Safe Register, HSE guidance, your insurer and your accountant.
Before you bid for your first commercial contract
- Your engineers' Gas Safe categories cover every appliance in the scope
- Out-of-hours cover is planned and costed, or you don't bid
- Price is per property per year, with no-access visits and admin included
- Remedial approval limits are agreed in writing
- Application dates, retention, CIS and VAT treatment are known before you sign
