The undisputed king of plumbing callouts. Blocked drains account for more service requests than any other plumbing issue — covering kitchen sinks, bathroom basins, showers, baths, and toilets. Grease build-up, hair, wet wipes, and foreign objects are the primary culprits. These jobs are typically urgent, relatively quick to complete, and generate strong repeat demand because clients who experience one blockage are statistically likely to experience another within 12 months if root causes aren’t addressed.

Leaking pipes range from minor nuisances to property-damaging emergencies depending on their location and severity. Under-sink leaks, leaking radiator valves, dripping connections, and concealed pipe leaks all fall into this category. Detection is often the most time-consuming part — particularly for concealed leaks behind walls or under floors — making leak detection equipment a worthwhile investment that also commands a higher per-job rate.

Boiler work is among the highest-value and most loyalty-generating services in a plumber’s portfolio. Repairs range from faulty thermostats and pressure issues to heat exchanger failures and gas valve replacements. Annual servicing is a predictable, recurring revenue stream — and clients who have their boiler serviced by the same plumber year after year are the most valuable, lowest-churn clients in the business. Gas-safe registered plumbers who offer combined repair and annual service plans have a significant competitive advantage.

Dripping taps are one of the most universally frustrating household problems — and one of the most common plumbing requests. Worn washers, damaged O-rings, faulty cartridges, and seized tap heads are all routine fixes that most experienced plumbers can complete in under an hour. While individual job values are modest, tap repairs are extremely high in frequency and often lead to adjacent upsells: clients who call about a dripping tap frequently end up replacing the full tap set, upgrading their kitchen mixer, or addressing associated pipework issues discovered during the visit.

Constantly running cisterns, broken flush mechanisms, cracked pans, and leaking toilet bases are all common and often urgent. A running toilet can waste over 200 litres of water a day — making clients highly motivated to get it fixed quickly. Toilet repairs encompass everything from a simple ballcock replacement to a full suite swap-out, and the wide range of job values within this single category makes it a strong contributor to overall plumbing revenue for businesses that handle volume efficiently.

No hot water is one of the most commonly reported household plumbing emergencies. The causes range from faulty immersion heaters and failed thermostats to airlocks, failing cylinders, and combi boiler pressure drops. Diagnosis is the critical skill here — quickly identifying whether the issue is electrical, pressure-related, or component failure determines both the fix required and the parts needed. Plumbers who arrive with a full diagnosis kit and common replacement parts close significantly more jobs on the first visit.

Cold spots, leaking radiator valves, noisy pipes, and failing thermostatic radiator valves (TRVs) are among the most reported heating complaints. Power flushing — clearing sludge from the heating system — is a high-value service that resolves multiple radiator issues simultaneously and commands a premium rate. Central heating work tends to cluster heavily in October and November as homeowners switch on systems that have been idle all summer, creating predictable seasonal demand spikes that well-prepared plumbing businesses capitalise on.

Full bathroom installations, shower enclosure fits, and bath-to-shower conversions represent the highest per-job revenue in general plumbing — and demand is strong year-round. These projects typically span one to three days, involve multiple trades, and require precise scheduling and materials coordination to avoid costly delays. Plumbers who can manage the full project — coordinating tilers, electricians, and decorators as well as completing the plumbing installation — command premium rates and build the kind of client relationships that generate years of referrals.

Burst pipes are the definition of a plumbing emergency — they cause rapid and significant property damage if not addressed within minutes of discovery. While they represent a smaller proportion of total job volume than routine services, they generate the highest urgency and often the highest per-hour revenue through emergency call-out rates. Cold snaps and returning holiday homeowners discovering frozen pipe damage are the primary demand triggers. Plumbing businesses with 24/7 emergency booking capability and rapid dispatch capture a disproportionate share of this high-value work.

Low or inconsistent water pressure is a frequently reported issue that has a wide range of potential causes — failing pressure regulators, partially closed stop valves, limescale build-up in pipes, failing pumps, or issues originating with the mains supply. Diagnosis requires a methodical approach and the right testing equipment. Businesses that handle pressure diagnostics efficiently — with documented testing procedures and a clear parts inventory — resolve these jobs faster and with higher first-visit fix rates, generating strong client satisfaction and repeat bookings.