The winter jobs, and why they are the season

Three processes run continuously on a boat and none of them stops when it is not being used. Salt water corrodes and finds its way into things; ultraviolet light degrades every synthetic on deck; and fresh water inside a system freezes, expands, and splits whatever it is in. The winter list is the annual defence against all three, and it is also the only time of year when a boat is accessible enough to look at properly.

It divides into work that keeps the boat safe, work that keeps it worth something, and work that makes next season pleasant. When time runs out, that is the order.

• Seacocks and skin fittings — Every hole below the waterline with a valve on it. They seize, they corrode, and a seized seacock is one that cannot be closed on the day something bursts. Operating them, servicing them, and knowing where every one of them is are the same job.
• Standing rigging, terminals and chainplates — The parts holding the mast up, most of which fail invisibly from fatigue and crevice corrosion rather than visibly from wear. Inspection is annual; replacement is on a much longer cycle and is a specialist judgement rather than a home one.
• Gas: the whole installation — Hose has a life, connections loosen, and a bubble tester or a proper leak check is the only way to know. Liquefied petroleum gas is heavier than air and collects in the lowest part of the boat, which is why this is a different order of hazard from the same appliance in a kitchen.
• Fire, carbon monoxide and gas detection — Extinguishers have dates, detectors have batteries and end-of-life dates, and both are checked rather than assumed. Carbon monoxide is the hazard common to every enclosed boat with a fuel-burning appliance and it kills people who were otherwise doing everything right.
• Lifejackets and safety gear — Gas cylinders, firing heads and hydrostatic units all expire, and a lifejacket that has been fired once is not serviceable until it has been rearmed. Flares have dates and a disposal route that has to be arranged rather than improvised.

• Anything holding fresh water — Tanks, pipework, the calorifier, the heads, and the engine’s raw and fresh water circuits. Draining or protecting each of them is the classic winterisation job and the classic expensive omission.
• The engine — Oil and filters changed before the lay-up rather than after, so the engine does not spend the winter sitting in used oil. Impellers, anodes and belts are inspection items on the same visit.
• Batteries — A battery left discharged over a cold winter is often a battery that has been replaced by spring. What the right treatment is depends entirely on the chemistry, and getting that wrong is its own way of destroying them.
• Ventilation and damp — A closed boat grows mould in every locker. Cushions on edge, lockers open, and airflow through the accommodation cost nothing and save an interior.
• Sails, canvas and lines — Sails come off, get washed and dried properly, and go somewhere dry — and this is the natural moment to have them looked at. Ultraviolet degradation is why covers exist and why lines eventually feel stiff.

Whether a boat needs antifouling every year depends on where it is kept, how much it is used, what is already on the hull and which system is in use, and the answer genuinely differs between two boats in the same marina. What does not differ is that the job is far easier immediately after lift-out, while growth is soft, than it is in the spring after a winter of drying.

The same visit is the only reliable opportunity to look at the parts of a boat that are normally underwater: anodes, the propeller and its shaft or leg, the rudder bearing, and the hull itself for damage, blistering and moisture. Several of those are cheap to address on a trailer or in a cradle and very expensive to address afloat.