Haul-out and antifouling: how often, how it goes, what to check

The haul-out is the most regular maintenance job on a boat and one of the most useful: the boat comes out of the water, the hull is cleaned and inspected, the antifouling that stops weed and shellfish from settling is renewed, and the time out of the water is used for everything that lives below the waterline. It is also the only moment of the year when you really see the condition of the boat. This guide explains how often, how it goes, what to look at, and how to read a quote.

1. How often?

• Boat kept afloat all year round: every year, that is the standard interval. In the Mediterranean or in warm water, fouling builds up faster; in the Channel or the North Atlantic, some boats last two seasons with a suitable antifouling and a boat that sails.
• Boat laid up ashore for the winter: the antifouling is redone at launch, in spring; the pressure wash is done at haul-out, in autumn, while the fouling is still soft.
• Boat on a trailer or permanently ashore: no antifouling needed; a rinse after each outing is enough.

A dirty hull means half a knot to a knot less under sail, higher fuel consumption under engine, and an engine that overheats if the through-hulls are blocked. Putting off a haul-out is paid for in fuel and comfort.

2. How it goes

1. Haul-out: with a travel lift, a crane or onto a cradle. This is the moment to photograph the hull as it comes out — the best proof of the boat’s real condition.
2. Pressure wash on the haul-out area, straight away, before the fouling dries. Haul-out areas collect and treat the wash water; an “unofficial” haul-out on a beach or an unequipped slipway is forbidden in most French ports and coastal municipalities.
3. Inspection of the bare hull (see the next section).
4. Preparation: light sanding of the old antifouling (mask, dust extraction: the dust is toxic), filling of chips, touching up the primer where the hull is bare or around new through-hulls.
5. Applying the antifouling: one or two coats by roller, an extra coat on the waterline and the leading edges of the keel and rudder. Anodes, transducers and the propeller are not painted with a standard antifouling (specific products exist for metal parts).
6. Replacing the anodes, checking and greasing the through-hulls, stern gland and propeller.
7. Relaunch within the time given by the paint manufacturer (often a few days at most for eroding paints), then checking the through-hulls one by one once opened.

3. Choosing the antifouling

• Eroding (self-polishing): wears away as the boat moves, does not build up, suited to boats that sail regularly. The usual choice for cruising.
• Hard antifouling: does not erode, withstands cleaning by a diver, better for fast boats or boats that stay in port for long periods; builds up and calls for stripping every few years.
• Compatibility: an antifouling cannot go on top of just any other. Note the product used (brand, type, colour) in the log: the next boatyard will need it, and switching to another family calls for a tie-coat primer.
• Aluminium: copper-free products only, otherwise the hull suffers galvanic corrosion.
• Drives and propellers: specific products; a copper-based hull antifouling on an aluminium drive destroys it.

4. What to check while the hull is bare

This is the part that is worth the price of the haul-out. Do it yourself, or ask the boatyard to do it and write it down.

• Osmosis blisters: small bubbles under the gelcoat that release an acidic liquid when pierced. A few isolated blisters can be treated locally; a hull covered in them is treated by peeling and rebuilding, which is a major job. A yearly haul-out with photos lets you follow how it develops.
• Anodes (shaft, propeller, drive, hull, keel depending on the boat): replace them as soon as they have lost half their volume. An anode still intact after a year is not good news: it is not in electrical contact.
• Through-hulls and seacocks: operate each seacock, check for corrosion (brass turning pink = dezincification, to be replaced), grease; check and grease at least every two years.
• Propeller, shaft, cutless bearing: play of the shaft in the bearing, condition of the blades (impacts, corrosion), fastening of the propeller; folding or variable-pitch propeller: play in the blades, greasing.
• Stern gland or shaft seal: condition of the packing or the bellows; replacing the rotating seal is recommended at the interval set by the manufacturer.
• Saildrive leg: condition of the diaphragm seal (the manufacturer sets its replacement interval, often seven years), drive anode, no milky oil.
• Rudder: play in the bearings, cracks where the stock meets the blade, water weeping out (rudder full of water, to be dealt with).
• Keel: the keel-to-hull joint (a crack or running rust means the keel bolts need checking), condition of the keel bolts from the inside.
• Transducers (depth sounder, log): cleaned, log paddle wheel turning freely.
• Gelcoat and waterline: clean boot top, chips, signs of impact on the bow or keel to have looked at.

5. Reading a haul-out quote

Prices vary a great deal from one sailing area to another; what does not vary is the structure. A complete quote includes:

• handling (haul-out and relaunch), charged per boat or per metre;
• the pressure wash;
• storage ashore, per day or per week — the item that climbs if the boat waits;
• labour for preparation and application, in hours;
• the paint (number of litres and coats) and consumables;
• the anodes, and any work found to be needed (through-hull, stern gland, touch-ups), listed separately.

Doing the haul-out yourself is common and cuts the bill down to handling, storage and paint; what matters then is to date it, photograph it and keep the receipt for the paint and anodes, so that the job is documented and not just declared.

6. When buying a used boat

Ask for the date and photos of the last haul-out, the product used, and the condition of the anodes and through-hulls noted at the time. A seller who presents a verified sale file with a recent, documented haul-out spares you a blind survey haul-out; conversely, if the last haul-out was more than a year ago, plan one as soon as you buy — it is the best moment to get to know your boat anyway. The buying checklist covers these points, and the maintenance cost guide puts the haul-out back into the annual budget.