Quick answer
A composite door service is a roughly 45-minute check covering cylinder lubrication, gearbox greasing, hinge adjustment, seal treatment, drainage clearance, compression checks and slab waxing. It typically costs £85–£120, and doing it annually can extend a door's useful life by several years by catching small problems before they escalate.
Overview
A proper service: lubricate cylinder, grease gearbox, adjust hinges, treat seals, clear drainage, check compression, wax slab, check hardware. £85-£120 typical.
Symptoms
- It's been more than 12 months since the last service.
Common causes
- General wear.
What's actually included in a proper service
A composite door service isn't just a quick wipe-down and a squirt of oil — done properly it's a systematic check of every moving and weather-critical part of the door. The multi-point lock cylinder gets lubricated with the correct graphite or PTFE-based product (never household oils, which attract grit and gum up over time), and the gearbox behind the handle gets greased to keep the locking bolts moving smoothly.
Hinges are checked and adjusted for any drift in alignment, the compression seal is inspected for even contact all the way round and treated with a silicone conditioner to keep it supple, and drainage slots at the base of the outer frame are cleared of any debris that's accumulated. Hardware — handles, letterbox, spy-hole if fitted — gets checked for looseness, and the slab itself is typically waxed or conditioned to protect the finish.
- Cylinder lubrication (correct product, not household oil)
- Gearbox greasing
- Hinge inspection and adjustment
- Seal inspection, treatment and compression check
- Drainage slot clearance
- Hardware tightness check
- Slab wax/conditioning treatment
Why annual timing matters, especially in Cornwall
A year is roughly the point at which small issues on a well-installed door start to become noticeable without yet being serious — a cylinder that's beginning to feel slightly stiffer, a seal that's compressing a touch unevenly, a hinge that's drifted just enough to need minor adjustment. Catching these at the annual point means a quick fix as part of routine servicing rather than a standalone repair call-out later.
Coastal exposure in Cornwall makes the annual interval more valuable than it would be inland — salt-laden air accelerates hardware corrosion and UV exposure degrades seals faster, so a door that might comfortably go 18 months between services inland often shows more wear after 12 months on an exposed coastal elevation.
The financial case for servicing
A service costing roughly £95 sits well below the cost of most reactive repairs it helps prevent — a multi-point mechanism replacement alone can run to £180–£320, and that's exactly the kind of failure that's often preceded by months of a gearbox running dry without lubrication. Viewed over a door's lifetime, a handful of £95 services is consistently cheaper than the repair bills that tend to follow neglect.
There's a less obvious cost too: a door that isn't serviced tends to develop compensating wear, where one worn part causes another to work harder and fail sooner — a dropped hinge putting extra strain on the lock, for example. Regular servicing catches issues before this kind of knock-on wear sets in.
Light maintenance you can do yourself between services
A full professional service isn't the only maintenance that matters — you can reasonably keep on top of a lighter version yourself between annual visits. Wiping the slab down periodically with mild soapy water, keeping an eye on handle and letterbox screws for any looseness, and giving hinges a light silicone spray if they start to feel dry are all sensible, low-risk tasks that don't require any specialist tools or knowledge.
What we'd steer clear of doing yourself is anything involving the multi-point lock's internal gearbox or cylinder replacement, and any adjustment to the frame fixings — these need the correct parts and a proper understanding of how the mechanism is meant to behave when working correctly.
Servicing older or previously neglected doors
If a door hasn't been serviced in several years, the first visit often takes longer than the standard 45 minutes and may uncover one or two issues that need addressing alongside the routine service items — a seized cylinder needing replacement rather than just lubrication, for example, or seals that have hardened beyond the point where conditioning alone will restore them. This is worth budgeting for on a first service if the door's history is unknown, such as when you've bought a property with an existing composite door of uncertain age.
Servicing for holiday lets and second homes
Properties that see high guest turnover or sit empty for stretches between visits benefit particularly from a scheduled annual service, since there's no owner living on-site day-to-day to notice a stiffening lock or a hinge starting to drop. Booking a service to coincide with a quieter point in the letting calendar, such as between seasons, avoids disrupting guest stays and ensures the door is in good condition heading into the busier months.
Setting service intervals by exposure, not by calendar habit
A blanket 'service once a year' rule ignores how differently a door on an exposed clifftop elevation ages compared with one tucked under a porch three miles inland. Exposed coastal — direct salt-laden wind and driving rain — benefits from an annual service. Sheltered coastal or exposed inland sits comfortably at 18 months. Sheltered inland properties can often stretch to 24 months without meaningful risk, provided nothing looks obviously wrong in between.
These bands aren't guesswork — they reflect how much faster UV, salt and wind-driven moisture degrade compression seals, silicone and lubricated hardware on an exposed elevation compared with a sheltered one, sometimes by a factor of two.
What a full service actually includes
A proper service covers hinge lubrication and adjustment, multi-point lock mechanism lubrication and cycle testing, compression seal inspection and replacement where perished, drainage slot clearing, and a check of the external silicone line for cracking or lifting. It typically takes 30 to 45 minutes per door and costs £45–£85 depending on how much needs doing beyond the basic check.
Insurance-backed guarantees and servicing obligations
Some manufacturer warranties and insurance-backed guarantees include a condition that the door be maintained reasonably — not a specific service schedule, but evidence that obvious faults weren't ignored. Keeping a simple record of service dates and what was done protects you if you ever need to make a warranty claim and the manufacturer questions whether the fault was down to neglect rather than a product defect.
Second homes: building servicing into a changeover routine
For holiday lets and second homes, the most reliable way to keep a servicing schedule on track is tying it to an existing changeover or seasonal visit rather than relying on a separate reminder that's easy to miss when you're not living in the property day to day. An end-of-season check before the door faces a full winter unoccupied is particularly valuable, since problems that develop over winter often aren't caught until spring letting begins.
The cost logic of servicing versus reactive repair
A £45–£85 annual service on an exposed coastal door is set against the realistic alternative: a failed compression seal left unnoticed can let enough moisture through to require a full re-seal (£90–£160) or, if it's tracked into the frame, a re-fix (£120–£220). Over a five-year period, planned servicing on an exposed property typically costs less than dealing with even one deferred fault reactively, without accounting for any resulting damp or damage.
Typical repair costs in Cornwall
| Work | Typical price | Notes |
|---|---|---|
| Standard annual service | £85–£120 | Full check and treatment, ~45 minutes |
| First service on neglected/unknown-history door | £110–£160 | May uncover additional minor issues |
| Additional repair found during service | £75–£320 | Quoted separately before proceeding |
Guide prices only — we confirm the cost after seeing the door.
When to call a professional
- For a full annual service.
Prevention
- Annual service extends door life by years.
