How to Clean a Kayak: Inside, Outside, and Mildew Removal

Kayaks are built from several different materials (plastic, composite, or wood) and each one responds a little differently to soap, pressure washers, and long-term storage. Since most kayaks spend more time in storage than on the water, the biggest cleaning challenge is usually what you find when you pull the boat out of the garage months later.

Here’s the simplest, most effective way to clean a kayak, keep mildew from taking hold, and get it ready for the next season.

Quick Answer

The simplest way to clean a kayak is with a bucket of warm, soapy water and a sponge. Rinse the soap off with a hose, dry the boat with a microfiber cloth, and treat any mildew with a mild bleach-and-water solution. Store the kayak dry, out of direct sun, and away from damp enclosed spaces.

Cleaning the Outside of Your Kayak

The exterior is the easy part. It’s designed to get wet. A basic wash removes the dirt, algae, and grime that build up on any hull.

What you’ll need:

• A bucket
• A sponge (an auto-care sponge works well)
• Soap: car shampoo, dedicated kayak soap, or a few drops of dish soap
• A hose or other source of running water
• A microfiber cloth for drying

Steps:

1. Mix soap into a bucket of warm water.
2. Dip the sponge and wash down the hull, applying more pressure on stubborn dirt spots.
3. Rinse the sponge, then hose down the entire kayak to remove all soap residue.
4. Dry the surface with a microfiber cloth before storing.

Can You Pressure Wash a Kayak?

It depends on the material:

• Wood kayaks: avoid pressure washers. High-pressure jets can strip the wood’s protective finish and compromise its waterproofing.
• Composite kayaks: pressure washing is generally fine, but stay clear of thin sections of the hull and go easy around decals, which can peel under direct pressure.
• Plastic (polyethylene) kayaks: the most pressure-washer-friendly option. These durable hulls can typically handle pressure washing inside and out without issue.

Cleaning the Inside of Your Kayak

The interior is trickier, especially on sit-inside kayaks with a small cockpit opening.

• Wooden kayaks: stick to a damp (not soaked) cloth wipe-down. Excess moisture left inside a wood hull is exactly what invites mildew.
• Composite kayaks: a low-pressure hose or sprayer works, but be careful around any thin or flexible sections of the hull.
• Plastic kayaks: these can generally handle a hose or even a pressure washer on the interior.

Whatever the material, the critical step is getting all the water back out afterward. Standing water inside the hull is the number one cause of mildew and odor.

Removing Mildew from a Kayak

Mildew thrives in damp, enclosed spaces: exactly what the inside of a stored kayak can become if it isn’t dried out first. It can affect any hull material, though it’s most common in composite and plastic kayaks where water wasn’t fully drained before storage.

To treat it:

1. Mix a mild bleach solution: about a capful (roughly 10ml) of household bleach per bucket of water.
2. Wear rubber gloves; bleach can irritate skin.
3. Scrub the mildewed areas with a sponge soaked in the solution.
4. Rinse thoroughly with clean water until no bleach smell remains.
5. Let the kayak sit in the sun for an hour or so to fully dry before storing it.

Should You Wax a Kayak?

Wax won’t make a kayak faster, despite the myth. What it does is add a protective layer against UV damage and make dirt easier to shed, meaning less frequent cleaning over the season. You can use a kayak-specific wax or general automotive wax.

Storage Tips to Prevent Repeat Cleaning

• Store the kayak completely dry: never with water pooled inside.
• Choose a dry location; damp garages, sheds, or basements accelerate mildew growth.
• Keep it out of direct, prolonged sunlight to protect the hull finish.
• Rinse kayaks used in saltwater with fresh water after every outing to prevent salt buildup and corrosion of hardware.

Frequently Asked Questions

How often should I clean my kayak?

At minimum, every couple of weeks during regular use, and always after a muddy or particularly dirty trip. Saltwater kayaks should be rinsed with fresh water after every session.

What’s the best soap to use on a kayak?

A car-wash shampoo, dedicated kayak cleaner, or a mild dish soap all work well. Avoid harsh degreasers or solvents that can damage plastic or gel coat.

Can I use bleach on the outside of my kayak?

Yes, in a diluted solution for stubborn mildew or staining, but rinse thoroughly afterward. Full-strength bleach can degrade some hull finishes over time.

Conclusion

Cleaning a kayak isn’t a heavy chore, but staying consistent with it (a rinse after saltwater trips, a full wash every couple of weeks, and a thorough dry-out before storage) is what actually extends the boat’s lifespan. Skip the mildew problem entirely by making sure your kayak is bone dry before it goes into storage, and it’ll be ready to go the next time you want to get on the water.