The Bottom (Paint) Line

The Bottom (Paint) Line

It’s simple: The purpose of bottom paint is to prevent barnacle growth and other evidence of fouling on the boat’s bottom.

However, the paint itself is not designed to last forever. For cruiser-type boats that are used often, an ablative paint that wears off over time is usually the best choice. Today’s paints and anti-corrosion primers are more environmentally friendly than ever, with low volatile organize compounds (VOCs).

The annual haul-out is the perfect time to check the condition of your bottom paint. For well-maintained boats, the bottom-painting procedure is similar for fiberglass, aluminum and steel-hulled boats. The bottom is mechanically sanded to remove any growth, profile work is done, then the ablative paint is applied with either a roller or sprayer.

However, a fiberglass boat that hasn’t been hauled in a few years would probably have blister problems. Steel boats that have been in the water for a few years with no cleaning would likely be suffering from corrosion, as would aluminum boats. Boats with these problems need more preparation work, such as removing the paint down to the substrate and applying a primer/barrier system. The additional time and labor will likely increase the costs.

We got issues

“Hauling out every year to year and a half keeps the bottom clean and makes the boat cheaper to maintain in the long run,” explained Tom Krigger, general manager at Bradford Marine in Fort Lauderdale. Bradford is a full-service yard with 180 employees that can haul-out boats up to 140 feet with a 300-ton Synchrolift. “By not letting the bottom degrade less work has to be done.”

Bottom paint from Interlux, Pettit and Sea Hawk are among the most popular brands used by boat owners in the 40- to 80-foot range.

“New for this year with Interlux is Aqua-One™ Performance Ablative antifouling,” said Matt Anzardo, marketing manager at Interlux. “This is a water-based antifouling and the ablative action wears away when the boat is being used, minimizing paint build up while providing protection.”

Water-based antifouling paints, which can be applied over most antifoulings, are popular because they are easy to apply and clean up.

They’ve got solutions

“Pettit Marine Paint’s focus continues on the rapidly growing Hydrocoat family water-based product line which is our No. 1 seller,” said Don Zabransky, Pettit’s vice president of sales and marketing. “The adoption from both consumers and boatyards has grown drastically over recent years, given the many benefits such as ease of application, environmentally friendly with low VOCs and superior antifouling performance.”

Pettit’s Hydrocoat ECO CopperFree bottom paint has been on the market for more than three seasons. This antifouling paint is a true copolymer ablative, which can be applied in very thin coats resulting in less buildup and drag. Indeed, Pettit recently conducted a survey of Hydrocoat users, which reflected that 98 percent were pleased with its results and plan to use it again.

“There is no reason to change if the paint is working well,” Krigger said. “At Bradford we keep track of what our customers use and work closely with the paint manufacturing reps. The reps know their product lines and what they can and can’t do, as well as what is new.”


Some boaters scrub their own hull bottom monthly or quarterly, or hire a diver service to do it. This can extend the time between haul-outs for bottom paintwork but obviously does not address running gear or through-hull maintenance. Also be aware that when a diver cleans the bottom, that diver is cleaning off the paint that protects the bottom.

The proper sanding and removal of old paint and the prep of the bottom is crucial to getting a long-lasting paint job. Paint is normally applied with a roller, although some yards apply paint with a sprayer, especially on larger boats. One coat of paint is normally sufficient for boats that will be hauled annually.

If a hull does need to be stripped down to the substrate, Sea Hawk’s new Tuff Stuff LOW VOC products comply with rigid VOC limits set by the California Air Quality Management Board. Tuff Stuff LOW VOC is effective for blister protection on fiberglass or as a bilge coating because of its resistance to both water and oil. As a universal primer, Tuff Stuff LOW VOC can be used for corrosion protection on most metals below the waterline and for priming any metal surface.

“Tuff Stuff LOW VOC is an extremely high-build two-part epoxy system that dries fast, enabling the application of a complete barrier system and bottom paint to most vessel hulls in just two days saving boat owners time and money while minimizing VOC emissions to preserve air quality,” said Sea Hawk CEO Erik Norrie. “The new Tuff Stuff LOW VOC line is one way in which we provide marine service professionals and do-it-yourselfers the solutions they need to protect and enhance the longevity and performance of their vessels while preserving the air quality for all.”

— By Doug Thompson, Southern Boating Magazine March 2016


Bradford Marine:

Huckins Yacht Corp: HuckinsYachtCorp 


Pettit Marine Paint:

Sea Hawk Paints: