Boat Mildew

How to Prevent Mildew on Boat Seats

Boat owners are constantly providing maintenance, but the environment that boats are a part of is also extremely harsh to them. Water is the universal solvent, after all, but even aside from the wear on the hull, the shortage of electronics, and the corrosion and pitting that comes from saltwater, the perpetual moisture creates the perfect breeding ground for mold and mildew.


What Causes Mildew?

Mold and mildew spores are just about everywhere, and they’re always looking for new locations to thrive in. When boat owners don’t properly clean their boats, inspect for and repair damage, and winterize, mold and mildew will seize the opportunity to set up shop.

The two biggest factors for mildew growth are warmth and humidity. It, alongside mold, can still grow in cold conditions, though; it’s just that the two grow faster when temperatures rise. 


Why Is Mildew a Problem?

A bit of mildew might not seem like a big deal, but it can cause a host of headaches, including (but not limited to) the following:

1. It’s Unsightly

No one finds a boat covered in mildew and mold attractive, and unchecked mold growth is often taken as a sign that the boat is poorly maintained. That can be especially problematic for owners who want to sell their boats for top dollar. 

2. It Can Aggravate Health Problems

Moldy and mildewy boats are more than an aesthetics issue; they can irritate the respiratory systems of those with asthma and similar conditions. Even relatively healthy individuals may respond to continued mold exposure with coughs, watery eyes, and sneezing. They may even develop a rash or other form of skin irritation.

3. It Smells Bad

The odor of mold and mildew is musty, biting, and simply unpleasant. It can also be difficult to remove, especially if the growths are left unchecked for long periods.

4. It Can Damage Your Boat

Though mold and mildew can enjoy building and growing on your boat’s surface, they won’t always stay there. Mold will work its way into wood, fiberglass, and vinyl, causing each to weaken, warp, and break.


Don’t Give Mildew an Opportunity

You can keep mildew from showing up and ruining your boating experience in the following ways:

1. Clean Your Boat

Deep clean your boat every four to 12 weeks if it’s on the water and every six months if it’s dry-docked. Still, you ideally should be at least wiping down and rinsing your boat after every use, including the seats.

2. Use a Quality, Undamaged Cover and Dehumidify

If your cover has any rips or tears, patch them thoroughly, get a new cover, or consider shrink-wrapping your boat for even better protection. Whichever method you use, make sure you also use active ventilation, such as with a dehumidifier or desiccants, to keep moisture from building up inside the boat.

3. Allow for Airflow Inside the Boat

Stagnant air is friendly to mold, so make sure air can move throughout the boat by keeping all the cabinets, doors, lockers, and covers open. Solar vents or battery-powered vents are fantastic for pushing air in and out of boats, and if you have a boat larger than 30 feet, you should consider using two in a push-pull configuration.

4. Remove Items That Harbor Mold

Any cushions, blankets, sheets, mattresses, clothes, and other absorbent items should be stored elsewhere, as they can easily trap mold and mildew. Removing them will also improve airflow anyway.

5. Inspect Your Boat

Cleaning your boat is the perfect time to conduct an inspection. Check for water damage or areas where mildew might thrive unnoticed, and then repair and replace components fostering the substance.


Cleaning Mildew

If you’ve noticed that mold and mildew have begun to call your boat home, don’t panic, as you can get rid of it in the following ways:

1. Use Mildew Remover

Commercial mildew removal products will work as advertised, so long as they’re used as directed. For the safety of family members and pets, never clean the boat when they’re around, and seek natural mildew removers.

2. Use Bleach

You can certainly use bleach, just not straight bleach. Use a diluted solution of three parts water and one part bleach. After spraying and wiping off the mold, rinse thoroughly with water.

3. Use Baking Soda

With a quarter tablespoon of baking soda in a 16-ounce spray bottle and a soft brush, you can remove even stubborn mold patches. Make sure to rinse with water and let air dry.

4. Fumigate and Use a Mildew Blocker

These products are for after you remove the mold. Fumigating with a mildew control product will release chlorine dioxide to kill the spores and eliminate the odor. Follow that up with a mildew blocker to help keep the mildew and mold from quickly returning.


Never Give Up

All of these procedures are temporary solutions, given that, as long as your boat is in the water, it’s susceptible to mold and mildew. It’s up to you to protect your boat with routine maintenance and a watchful eye!


When it comes to keeping your boat clean, look to Captains Preferred Products boat cleaning supplies. Find everything you need to keep your vessel squeaky clean all season — always at the best prices.

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