PPM vs reactive maintenance: what the terms actually mean

What is a planned preventive maintenance (PPM) contract?

A PPM contract is a structured, scheduled programme of inspections, servicing, and minor works carried out at defined intervals, typically monthly, quarterly, and annually, to keep your mechanical and electrical (M&E) plant operating safely and efficiently. For commercial heating specifically, a PPM contract will include your annual Gas Safe boiler service, flue and combustion checks, system water quality monitoring, controls calibration, and documentation for compliance purposes.

The goal is to identify and address deterioration before it becomes a fault, extend asset life, maintain statutory compliance, and make maintenance costs predictable across your budget year.

What is reactive maintenance?

Reactive maintenance is the call-out model: you contact an engineer when something fails or performs below standard, and you pay for diagnosis, labour, and parts at the point of need. Some organisations operate on a fully reactive basis; others use a hybrid, where PPM covers statutory compliance and reactive covers everything else.

How they fit together

PPM and reactive are not mutually exclusive. Most mature FM contracts include a PPM schedule for planned, statutory, and preventive work, alongside a reactive call-out SLA for unplanned breakdowns. The question is not always “PPM or reactive” but “what should be on the PPM schedule, and what is the reactive response time and cost model for the rest?”

PPM vs reactive vs statutory compliance: clearing up the confusion

FMs sometimes conflate three distinct things. Understanding the difference protects you from compliance gaps and unexpected costs.

Statutory compliance covers the legal minimum: Gas Safety (Installation and Use) Regulations 1998 require annual inspection and certification of commercial gas appliances by a Gas Safe registered engineer. Pressure Systems Safety Regulations 2000 (PSSR) require a written scheme of examination for boilers above 0.5 bar, with periodic inspection by a competent person. L8 Legionella requires a risk assessment and written control scheme for hot and cold water systems. These are non-negotiable legal obligations, regardless of what maintenance model you operate.

PPM builds on statutory compliance to include condition monitoring, preventive servicing, minor adjustments, and works that keep plant performing efficiently between inspections. It turns compliance from a once-a-year event into a year-round programme.

Reactive maintenance addresses faults that arise between planned visits, whether covered under a contract SLA or charged at point of need.

A contract that only delivers statutory compliance is not a PPM contract. A PPM contract should demonstrably reduce reactive call-out frequency over time.

What a well-structured commercial PPM contract includes

Common inclusions across reputable commercial contracts vary by scope and tier. For heating plant specifically, look for:

Annual and periodic servicing Annual Gas Safe boiler service with combustion analysis, flue integrity check, safety device testing, and service record update. For cascade systems, each module serviced individually so plant can remain partially operational during works.

System water quality monitoring Magnetite and sludge contamination is one of the leading causes of premature commercial boiler failure. A properly scoped PPM contract includes periodic water quality checks, inhibitor dosing verification, and filter inspection and cleaning. Without this, a new boiler installed into a dirty system will degrade rapidly regardless of how well it is serviced.

Controls and BMS checks Calibration of thermostats, sensors, and zone controls. Verification of weather compensation curves and time schedules. BMS point checks and alarm log review. These are frequently omitted from basic contracts and represent significant energy savings when done correctly.

Compliance documentation Gas Safe certificates, PSSR inspection records, service reports, and water treatment records, all maintained and available for audit. This documentation is your evidence of due diligence as the responsible person.

Reactive call-out SLA Defined response times for breakdown attendance, typically differentiated between standard and emergency. For critical environments (care homes, schools, 24/7 facilities), the SLA for heating failure in winter should be specified clearly in the contract, not left as a general commitment.

Condition reporting and lifecycle advice Annual or periodic condition reports on plant age, performance trends, and recommended capital works. This is how reactive spend gets converted into planned capital investment and avoids emergency replacement at the worst possible time.

Common gaps that catch FMs out

Even reputable contracts can have exclusions that matter. Always check:

System condition at contract start. Many contracts will not cover pre-existing faults or deterioration. If your system has significant sludge contamination, corroded pipework, or non-compliant installations, these may be excluded until remediated. A reputable contractor will survey and document condition before contract start, not after the first call-out.

Cascade and complex plant. Some contracts price for a single boiler and do not adequately cover cascade systems, pressurisation units, plate heat exchangers, or low-loss headers. Confirm that all elements of your heating plant are in scope.

BMS and controls integration. Controls work is frequently excluded from basic contracts. If your boiler plant is integrated with a BMS, confirm that controls calibration and BMS interface checks are included, not treated as separate chargeable works.

Parts and materials. Labour-only contracts leave you exposed to variable parts costs. Understand exactly what is included: consumables only, or common mechanical parts (pumps, valves, sensors), or major components? The distinction matters significantly for budgeting.

Age and obsolescence. Some contractors decline to cover plant above a certain age. If your boiler is over 15 years old, confirm coverage terms and what the contract position is if the plant reaches end of life during the contract term.

When PPM makes financial and operational sense

Three factors that decide it for most FMs

Plant age and condition. Plant under five years old from a recognised manufacturer, correctly installed and commissioned, may need little beyond statutory compliance servicing in early years. From six to ten years onwards, the statistical probability of component failures increases and the value of a parts-inclusive PPM contract rises accordingly. Beyond 15 years, PPM combined with a lifecycle replacement plan is almost always more cost-effective than reactive repair.

Occupancy profile and criticality. A building where heating failure directly affects vulnerable occupants (care homes, sheltered housing, schools) or operational continuity (manufacturing, logistics, 24/7 offices) justifies a more comprehensive PPM contract with tighter SLAs than a low-occupancy storage facility. The cost of downtime in critical environments frequently exceeds the annual cost of a premium maintenance contract.

Budget certainty and risk profile. Reactive maintenance transfers cost risk from a fixed monthly or annual fee to variable, unpredictable call-out charges. In years with major component failures, reactive spend can comfortably exceed the annual cost of a comprehensive PPM contract. For FMs operating under fixed budgets or managing multiple sites, PPM converts unpredictable maintenance spend into a known line item.

Scenario comparison (indicative only)

A single reactive call-out for a commercial boiler fault, including engineer attendance, diagnosis, parts, and return visit, frequently costs between £500 and £2,000 depending on component and urgency. Two or three reactive incidents in a year, which is not unusual for plant over ten years old, can equal or exceed the cost of a full annual PPM contract that would have included those works preventively.

The cost of a winter emergency attendance during peak demand, when contractor availability is constrained and emergency rates apply, typically sits at the upper end of that range. Priority access under a PPM contract avoids both the premium cost and the operational disruption of waiting.

Corvée commercial PPM contracts across Northamptonshire

We have been working across Northamptonshire since 1983. Our Gas Safe commercial engineers cover Northampton, Kettering, Corby, Wellingborough, Daventry, Towcester, Oundle, and the wider county daily. Our commercial PPM contracts are built for FMs who need compliance, performance, and a contractor who takes ownership.

What Corvée commercial PPM includes

Annual Gas Safe boiler service with combustion analysis and full documentation. Flue and ventilation integrity checks. System water quality monitoring, inhibitor verification, and magnetic filter inspection. Controls and thermostat calibration. PSSR compliance support and documentation. Condition reporting with lifecycle recommendations. Reactive call-out SLA with priority response for contract clients. Discounts on upgrade works including powerflush, system filter upgrades, BMS integration, and smart controls.

For multi-site portfolios, we coordinate planned visits to minimise operational disruption and provide consolidated compliance documentation across your estate.

Why FMs in Northamptonshire work with Corvée

Gas Safe Registered, APHC member, Which? Trusted Trader, MCS-accredited. Commercial Gas Safe categories for non-domestic work. Fixed-price contracts with clear scope, no post-visit surprises. Real engineers, local knowledge, and honest advice on plant condition and replacement timing. 4.7/5 from 124 reviews.

If you are also planning a boiler replacement as part of your PPM programme, see our commercial boiler replacement guide for a full overview of specification, sizing, and installation.