Catamaran Surface Maintenance

Maintaining a catamaran is never just routine: it's a balance between techniques, product choices, environmental constraints, and personal preferences. Every material has its own specifics, and every owner develops their own maintenance habits over time. So there's no such thing as a perfect set of rules! Let's take a tour together of the main surfaces found on board catamarans, along with their maintenance methods, advantages, and points of caution.

The gelcoat is the main and most exposed surface. More than just a cosmetic layer, it's a genuine protective barrier for the boat's structure.
How you maintain it varies depending on the age of the catamaran:

Common methods :

• Regular washing: fresh water and mild soap are sufficient to prevent salt deposits from dulling the surface. Other products specifically designed for recreational boating, such as self-drying boat shampoos [e.g. Nautic Clean 01], can be used instead of mild soap.
• Polish: used to restore shine. There are several approaches :
• • Lightly abrasive polish → for regular maintenance,
  • More aggressive polish → for occasional restoration. 
•  Cire ou sealant : [type Nautic Clean 10] ou [type Seals Shield/Trishield] à appliquer lorsque le bateau est à terre

Advantages : 

• Restoration possible through polishing.
• Enhanced UV protection with waxes/polymers.

Points to watch : 

• Risk of thinning the gelcoat if polished too frequently.
• Results are highly dependent on the application method and product quality.

Diamond-pattern molded surfaces have been a characteristic feature of the decks of polyester-built boats since the 1960s. Their geometric pattern provides excellent grip… but makes cleaning more challenging.

Maintenance methods : 

• Soft brush and degreasing soap: to prevent dirt from becoming embedded in the textured surface.
• Steam cleaner or low-pressure washer: practical, but should be used sparingly to avoid blistering the gelcoat.
• Specialized non-slip products: some can slightly restore grip, while others provide hydrophobic protection [e.g. Seals Silkwalk].

Advantages :

• Excellent long-term durability with proper cleaning.
• Resistant to micro-scratches.

Points to watch :

• Difficult to restore: polishing is virtually impossible due to the textured surface.
• Dirt and organic residues can become deeply embedded.

Marine-grade stainless steel (316L in most cases) requires regular maintenance to prevent surface corrosion.

Maintenance methods : 

• Frequent rinsing with fresh water after sailing.
• Stainless steel cleaners: some are formulated with mild acids (phosphoric acid) [e.g. Nautic Clean 23] or [e.g. Seals Zerox].
• Manual polishing or microfiber cloth: to restore shine.

Advantages : 

• Easy to maintain with regular care.
• Effective, affordable, and non-aggressive products are readily available from marine chandlers.

Points to watch : 

• Frequent corrosion if maintenance is neglected for too long.
• Some abrasive metal polishes can scratch mirror-polished surfaces.

Winches, cleats, blocks, tracks, and cars are subjected to significant mechanical loads. Maintenance is not purely cosmetic: it also affects safety and ease of handling.

Common methods : 

• Rinse thoroughly after every outing.
• Use suitable lubricants:
  • Silicone or PTFE (dry lubricants) for moving deck hardware, in accordance with the manufacturers’ recommendations.
  • Specialized winch grease, in accordance with the manufacturers’ recommendations.
• Periodic disassembly, in accordance with the manufacturers’ recommendations.

Advantages : 

• Regular maintenance considerably reduces wear.
• Modern deck hardware is reliable and easy to disassemble.

Points to watch : 

• Wrong choice of lubricant = dirt build-up or blockage.
• Some products [e.g. WD-40] attract dust or retain salt.

Cockpit or sunbathing area upholstery can be made from technical fabrics, marine vinyl, or more innovative materials. At Excess, we opt for upholstery from Ruchaud, which is renowned for its water-repellent, breathable fabrics and coverings that are resistant to UV rays, mold, and wear.

Common methods : 

• Rinsing, mild soap and drying: the basics.
• Mould and mildew removers: use with caution to avoid damaging the fabric dye [e.g. Nautic Clean 04 or 21].
• UV protection: specific sprays can be used, although they are sometimes controversial as some products leave a sticky film.

Advantages : 

• Easy to maintain.
• Several restoration options (steam cleaning, treatments).

Points to watch :

• Mould can develop quickly if the upholstery remains damp.
• Some stain removers can cause fabric discolouration.

On a catamaran, sails are subjected to different loads than on a monohull: the loads are more constant due to the absence of a backstay or running backstays, while exposure to UV rays remains the same.

Common methods :

• Occasional rinsing with fresh water.
• Dry, well-ventilated winter storage.
• Professional cleaning to remove mould and embedded salt deposits.
• Annual inspection (stitching, battens, reinforcements).

Advantages : 

• Very long lifespan when properly maintained, particularly the Elvstrøm eXRP sails, with a tri-radial cut, selected by Excess and offered as part of the Pulse Line Pack.
• Modern membrane sails offer better UV resistance than in the past.

Points to watch :

• Aggressive chemicals can damage sail membranes.
• Delayed repairs are more costly and can weaken the sail.

Most boatbuilders and their distributors now offer a choice of several alternative deck coverings to traditional diamond-patterned non-slip surfaces.

A) Iroko

Tropical hardwood with an appearance similar to teak.

Maintenance :

• Oiling or saturation (two possible approaches).
• Gentle cleaning.
• Light sanding if necessary.

Advantages :

• Warm and inviting appearance.
• Natural material (FSC-certified Iroko used by the Beneteau Group).

Points to watch :

• Inevitable greying if left untreated.
• Sensitive to greasy stains.

B) Marine Cork

Maintenance :

• Mild soap.
• Very gentle pressure washing.

Advantages : 

• Highly slip-resistant.
• Comfortable under bare feet.
• Less sensitive to stains than Iroko.
• Easy to repair.

Points to watch : 

• Less visually premium than teak for some people.
• May become brittle and crumble over time.

C) Flexiteek / Synthetic PVC

Maintenance:

• Brushing with soapy water.
• No sanding, except for specific restoration work carried out by professionals.

 Advantages:

• High durability.
• Consistent appearance over time.
• UV-resistant.

Points to watch :

• Can become very hot in direct sunlight.
• Harder underfoot than real wood or cork.

Maintaining the surfaces of a catamaran is not just a matter of technique: it is also a way of living with and understanding your boat. Some sailors favour natural, minimalist methods, while others prefer specialised products to maximise longevity.

Every material has its own requirements, but one principle remains universal: consistency. Light but regular maintenance is far better than a heavy and costly restoration.

What do you have on board your catamaran (or what would you like to have)? And what are your maintenance routines?