How to Prepare Your Boat for Winter Storage

Proper winterizing and storage protect your boat’s appearance, lower maintenance costs, and preserve its resale value. Putting a boat to bed for the season involves far more than switching off the batteries and locking the hatch. A careful, methodical layup will prevent common off-season damage and make spring commissioning much easier.

Begin with a written checklist of everything that needs attention: service items, cleaning tasks, hardware checks, and any repairs. Whether you do the work yourself or turn the list over to a yard, start early. Don’t wait until the last few weeks before launch season.

Engine and Mechanical Systems

Service engines and mechanical systems before storage when possible. Fresh oil and properly maintained components help prevent corrosion and wear during the off-season. Old oil can contain acids and contaminants that speed internal damage, so changing oil and filters before layup is a worthwhile investment.

Air conditioners and water-cooled refrigeration systems require special attention. Drain and flush raw-water circuits, then run antifreeze through the intake and discharge lines. One method is to disconnect the intake hose at the seacock and pump from a bucket of antifreeze until it empties from the discharge. Alternatively, pour antifreeze into the sea strainer (with the seacock closed) and run the pump until antifreeze appears at the outlet.

Interior Cleaning and Ventilation

Thoroughly clean the interior to prevent mold and mildew. Wipe out lockers and cabinets with a mild bleach solution to remove any mold spores and to freshen the cabin. Place open trays of baking soda or use non-chemical moisture-control gel to absorb odors and humidity. A light application of lemon oil in drawers and cupboards will keep wood and surfaces smelling fresh.

Adequate ventilation is essential. Crack open lockers, hatches, and refrigeration doors to encourage air circulation. If the boat will be shrink-wrapped or stored indoors, leave hatches and companionways slightly open and ensure vents are installed in any shrink wrap to promote airflow and reduce trapped moisture.

Hull, Bottom, and Exterior Protection

Wash the hull and deck thoroughly with fresh water and a quality boat soap to remove salt, grime, and biological growth. Waxing the gelcoat or painted surfaces before storage adds a protective barrier against the elements. For boats stored ashore, pressure-washing the bottom removes slime, weeds, and barnacles; leaving such growth in place will make it far harder to remove in spring and can accelerate deterioration.

If you must shrink-wrap a painted boat, wrap only to the toerail. If covering to the waterline is unavoidable, place foam blocks along the skirt to keep the plastic off the paint. Trapped moisture between plastic and paint can cause blistering and lifting.

Consider applying antifouling paint in the fall if you haul out early. Some bottom paints have specific immersion windows, so follow product instructions.

Bilges, Drainage, and Dry Storage

Ensure the boat is thoroughly dry before storage. Bilge pumps remove much of the water but not everything—use a sponge to extract residual water. Remaining moisture promotes mold and mildew. If your boat has a bilge drain plug, remove it once the vessel is ashore so any water can drain. Store the plug in a visible place so it’s not forgotten at launch.

Boats stored on land must be properly supported: robust keel blocks and adjustable jackstands support the hull and prevent tipping. Place wooden blocks under the keel where most weight transfers to the ground. Chain jackstands together to prevent them from shifting during storms, but avoid securing tarps or covers to the stands themselves.

Batteries and Electrical

Neglected batteries often fail sooner than expected. If feasible, remove batteries and store them in a cool, dry location at home where they can be periodically charged. For batteries that are difficult to remove, fully charge them before layup and top them off monthly. Flooded lead‑acid batteries self-discharge faster than AGM or gel types and can freeze if left at low state of charge.

Sails, Canvas, and Rigging (Sailboats)

Sailboats require additional steps. Remove sails and have them cleaned, repaired, and stored properly—many sail lofts offer winter servicing and storage. Order any new or replacement sails during the off-season when lofts are less busy and turnaround times may be faster.

Inspect running rigging, furling lines, and canvas covers. Wash anchor rodes and mooring lines to remove grit and salt, rinse thoroughly, and hang them to dry before coiling loosely out of direct sunlight to prolong their life.

Pest Prevention and Security

Block exhaust ports and other openings to deter rodents and small animals from nesting aboard—chewed hoses have sunk boats. Inspect through-hulls, seacocks, and other openings and secure them where possible. For boats left in slips or on moorings, winter checks remain important: examine lines for chafe and ensure fittings are secure throughout the season.

Insurance and Regional Considerations

Check your insurance policy before layup. Many policies specify layup periods and conditions; verify coverage for boats left in the water or stored ashore and update the policy if necessary. Remember that freezing damage can occur in regions unaccustomed to severe cold; unexpected low temperatures have caused costly claims in more southerly areas.

Plan, Document, and Review

Create a detailed checklist and mark each completed task so nothing is overlooked when spring arrives. Start early, document work done, and hand your list to the yard well before launching if you’ve hired professionals. A well-organized winter layup saves time, reduces repair costs, and helps ensure a smooth and enjoyable return to the water.

November 2014 issue