Damage caused by moisture during wintering
The vagaries of winter weather can cause significant damage to a boat. There are two complementary solutions for the safe wintering of your boat which preserve both the interior and the exterior: heat-shrinkable film and moisture-absorbing bags.
Risks to external parts during boat wintering
The hull and deck are the parts that are most exposed not only to bad weather, but also to the sun. As salt water is corrosive it’s a good idea to keep your boat dry. If it’s parked near a wooded coastline, wind-blown plant debris can add to the salty moisture and settle on your boat, before rotting.
In addition, you should protect it from winter storms which can be violent and cause material damage.
Rinse the hull of the boat, as well as the upper part and the deck, in order to slow down corrosion of the metal parts. Open the drain plug and hatches to allow water to drain out. It’s a good idea to check the underwater hull, as well as the condition of the keel, the centreboard and the propeller shaft, depending on your type of boat.
If you can, dismantle and lay your mast on the deck, so that it can be included in the wrapping with the heat-shrink wrap.
Risks to internal parts during boat wintering
During the winter, in addition to the sea spray, your boat may be subject to the cold and all kinds of precipitation: rain, snow, hail, sleet, etc. No matter how well you close everything up, moisture can easily creep into all the interior parts of the boat. This turns into mould and gradually disintegrates all materials, especially the wooden and fabric parts that are part of the interior decoration.
Note that moisture and mould will also attract small pests.
Empty your boat
During the wintering of your boat, remove all your belongings: safety equipment (fire extinguishers, distress flares, life jackets, buoys, ropes), fishing, sports, or diving equipment. Take the opportunity to clean them and check that they are in good working order.
Check and protect sensitive items
Batteries do not cope well with not being used during winter. Rather than risk finding them flat when you take your boat out again, remember to protect them well.
The engine and its propeller must be cleaned before wintering the boat. The propeller shaft must be greased, and you must check the condition of the spinnaker seal, as well as the pin of the attached propellers.
The covering of the boat
Once all these steps have been completed, place moisture-absorbing bags inside the boat to complete the covering action.
You then need to wrap the boat in the heat-shrink film, using a mesh of straps to form a frame. If you have a small boat, you don’t need the straps.
The strips are horizontal and must overlap to provide a seal. If the mast is still in place, wrap around it. You are then going to use a hot air gun. Start by sealing the sail panels, then apply heat evenly so that the film shrinks and forms a rigid shell.
Then cut small openings to which you attach small ventilation grids. These create an airflow that removes moisture, without allowing wind-borne debris and pests to pass through.
You can also install zip doors that fit into the heat-shrink film. This allows you to have access to the interior of your boat. You can take advantage of the winter to do some renovation work. The access also allows you to change the moisture absorbers, which are only effective for two months.