Maintenance & Repair > How To Clean Your Hull

The importance of having and keeping a clean hull cannot be overstated. Boat owners can readily relate to the effects of a fouled hull: instead of a clean smooth hull cutting the water, marine growth creates drag, which in turn, reduces speed. The drag caused by fouling demands greater engine exertion to maintain speed, resulting in greater fuel use and added cost.

Not only is performance an issue here, but safety as well. Heavy fouling causes a boat to sit lower in the water, and negatively effects responsiveness, a dangerous combination in demanding weather conditions. As if the foregoing weren’t enough, the glues that marine organisms use to attach themselves to the hull cause damage to wood and fiberglass. In this How-To article, we’ll deal with getting rid of nasty, destructive barnacles and common slime and algae buildup.

If your hull is already menaced by barnacles and other annoying cling-ons, the solution is not easy. These shell-fouling organisms are pretty tough, as described by Interlux coatings, “Shell-fouling microscopic organisms are hatched in the sea. They swim around until they find a nice neighborhood (your boat bottom) to attach themselves to. The most common shell-fouling organism is the Acorn Barnacle. There are a variety of species that can grow to a whopping 7 centimeters in diameter. When barnacles adhere to the bottom of a boat, they continually grow and exert considerable pressure at the point of attachment. These creatures enjoy their resting place so much that even when removed, they leave a strong foundation, commonly called ‘husks.’ The adhesion of the husks is so great that the force necessary to remove them can tear the gelcoat, causing more damage”

To get rid of these pesty hangers-on, professionals suggest the following:

1. With the use of a pressure washer, remove the shells.

2. Use a long-handled floor scraper to remove as much of the barnacle as possible

3. Use a paint scraper to remove the husks, such as our Embee Heavy Duty Scraper. (Pros suggest not using sandpaper to do this, it may remove too much fiberglass)

4. Use a cleanser and lime remover to clean the remaining residue. We offer several, including the following:


Star Brite Stainless Steel Bristle Utility Brush With Scraper
Vertglas Restoration System
Starbrite Instant Hull Cleaner
Starbrite Boatcare in a Bucket
EZ on EZ off Hull and Bottom Cleaner
Meguiar’s Boat/RV Fiberglass Oxydation Removal Kit
Star Brite’s Instant Hull Cleaner
Star Brite Boat Bottom Cleaner, Barnacle and Zebra Mussel Remover
Toon-Brite Fiberglass Cleaner
For a cleaning brush, try our  Star Brite 10 Big Boat Bi Level Brushes



5. Lightly sand and apply two coats of antifouling bottom paint.

For those with new boats who don’t want to deal with the backbreaking process described above, there is one solution; don’t let your hull get fouled up. The old adage that an ounce of prevention is better than a pound of cure is true. It is always easier to keep something clean than to make it clean. Once organisms attach to the hull, they quickly multiply, and the more time expires the more difficult it becomes to remove them. The ounce of prevention needed is antifouling.

Antifouling has been called the most important painting job carried out by boat owners. The type of antifouling paint you use will vary depending upon several considerations, including environmental conditions and the material makeup of your hull. To be certain which antifouling paint to use, it is best to contact the manufacturers of these products, such as Interlux. Manufacturers provide compatibility charts to match the new product with the previous antifouling paint on your boat. For your convenience, we have provided a compatibility chart and numbers to our antifouling manufacturers at the end of this article.

You can apply antifouling to your own boat without expensive professional application. Boat-specific information is readily available and the process is easy enough to accomplish masterfully, even for those among us without painting skills. That leaves no excuse for not protecting your investment with antifouling. Lets get painting!

If your main concern is not barnacles and mussels but grime and slime, then there are several products that make it easy to keep a clean hull. For Slime and Algae buildup, any of the hull-cleaning products listed above will do the trick. Some of these are almost labor-free, with a spray on, spray off solution.

So, whether you’re a first time boat buyer wanting to keep your hull shiny and new, or an old veteran battling entrenched fouling, iboats.com offers the products and solutions to meet your needs.

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