Corrosion Protection
Corrosion protection is a crucial aspect of maintaining the longevity and performance of marine vessels, including boats and ships. Saltwater is a major cause of corrosion in marine environments. Marine paints and coatings play a vital role in preventing corrosion and damage to the hull and other metal surfaces by acting as a sacrificial barrier.
As a trusted choice among boat owners, Promain offers a range of marine paint products designed to provide a protective coating against corrosion, moisture, and organisms such as algae. With a wide range of products available, including black tar varnish, boat owners can find the ideal solution for their corrosion protection needs. Whether you’re looking for a regular price or a sale, Promain has a variety of options to suit your budget and project requirements.
Cold Galvanising for Boats – Trusted Zinc Protection from Promain
Saltwater is unforgiving. For boat owners, corrosion isn’t just a surface issue—it can shorten the life of essential metal components, from hull fixings to trailers. That’s why cold galvanising has become a trusted choice in marine maintenance. Promain supplies a focused collection of zinc-based coatings designed for boats, ships and yachts. These paints create a tough, protective coating that acts as a sacrificial barrier, with zinc reacting first as a sacrificial anode to protect the steel beneath from rust, algae, moisture and organisms commonly found in and around the waterline. This process is known as galvanic protection.
What Makes Cold Galvanising So Effective?
Cold galvanising involves applying a high zinc-content coating to bare metal. When exposed to water, oxygen, or salt, an electrochemical reaction occurs where the zinc reacts first - protecting the steel beneath. It acts as a sacrificial barrier, which helps extend the working life of marine metals significantly. Whether you’re maintaining a canal boat, refurbishing a yacht, or restoring a trailer, cold galvanising should be your first layer of defence.
Types of Cold Galvanising Paint
Cold galvanising paint is a type of coating that provides a protective layer against corrosion without the need for welding or heat. Promain offers a range of cold galvanising paints, including single-pack and two-pack epoxy primers, designed for use on metal surfaces above and below the waterline. These paints are ideal for boat owners who want to protect their vessels from corrosion without the hassle and expense of traditional galvanising methods.
With a range of prices available, including regular price and sale options, boat owners can find a cold galvanising paint that suits their needs and budget. Whether you’re looking for a brush, spray, or roller application, Promain has a product that’s easy to apply and provides long-lasting protection against corrosion.
Benefits of Cold Galvanising
Cold galvanising offers a robust and long-lasting protective coating for metal surfaces, making it an ideal choice for boat owners aiming to shield their vessels from corrosion. Unlike black tar varnish, which may not provide the same level of protection, cold galvanising delivers a brilliant solution for ensuring the longevity of your boat. This process involves applying a high zinc-content coating that acts as a sacrificial barrier, effectively protecting the underlying metal from moisture, algae, and other marine organisms.
With a regular price that is competitive, cold galvanising is a cost-effective method to safeguard your boat’s performance and structural integrity. By choosing cold galvanising, boat owners can trust that their vessels are well-protected against the harsh marine environment, ensuring years of trouble-free use.
When Should I Use Cold Galvanising?
You should apply cold galvanising paints:
-
After welding repairs
-
When stripping rust or old primers
-
Along the waterline and bilge areas
-
On steel hulls, chains or anchor points
-
Around boat trailers and exposed structural components
If you’re planning a project involving marine-grade metalwork, adding zinc-rich coatings is one of the most effective ways to prepare your boat for long-term exposure. Proper surface preparation is crucial before applying cold galvanising paints to ensure optimal adhesion and protection.
Promain: Trusted Suppliers of Marine Paints Since 1908
Promain stocks a specialist range of boat paints, primers, undercoats and topcoats from respected marine paint manufacturers. While our full marine paints range includes items like black tar varnish and bilge coatings, this section is focused on our zinc-based systems for corrosion protection.
We sell only genuine products at a regular price, with a trusted reputation for performance at sea.
Cold Galvanising vs Traditional Marine Paints
Marine glosses and topcoats protect against sunlight and surface wear. But when it comes to corrosion, standard paints alone aren't enough. Zinc-based galvanising coatings work inside the metal, bonding chemically to prevent rust at its root.
If your surface is bare steel or iron, use a zinc primer first - then add your colour or antifouling finish later.
Use Cold Galvanising on These Surfaces
-
Metal hulls
-
Keel plates and bow sections
-
Fixings below or around the waterline
-
Steel railings and guards
-
Boat trailers and steps
-
Onboard welding points
It’s also ideal for areas that get wet frequently but don’t stay submerged, such as bilge spaces or anchor bays.
Key Benefits for Boat Owners
-
Slows down corrosion and rust
-
Adds years to your metalwork's life
-
Easy to apply with a brush or spray
-
Helps topcoats stick better
-
Suitable for all water-facing projects
-
Available now from Promain’s stock with fast delivery
Surface Preparation
Surface preparation is a critical step in ensuring the effective application of marine paints and coatings. Before applying any paint or coating, it’s essential to clean and prepare the surface to ensure a strong bond between the paint and the metal. This includes removing any dirt, grime, or existing coatings, and applying a primer if necessary. Promain offers a range of primers and undercoats designed to work with their marine paint products, providing a strong and durable bond that will last for years to come.
By following the recommended surface preparation procedures, boat owners can ensure that their marine paint or coating application is successful and provides long-lasting protection against corrosion and damage.
Step-by-Step Application Guide
-
Sort out surface prep – remove any rust, flaky paint or dirt using a wire brush or sander.
-
Clean thoroughly – use a degreaser or solvent to ensure the surface is dry and free of oils.
-
Apply product – shake sprays well, or stir tins before brushing. Always apply in a well-ventilated space.
-
Let it cure – follow the drying times on each product.
-
Add topcoat (if needed) – choose a compatible finish if you're applying a colour coat or antifoul on top.
Drying and Curing
Marine paint products are designed for easy application and quick drying, making them a convenient choice for boat owners. Whether you’re working on the hull, applying primers, undercoats, or topcoats, there is a range of paints and coatings available to suit your project needs. The drying and curing times can vary depending on the type of product and the surface it is applied to, but with the right advice and guidance, you can achieve a smooth and even finish.
Marine paints are formulated to protect your boat from corrosion and add a touch of color, all without the need for specialised skills like welding. By following a clear and easy-to-follow application process, you can ensure that your paint job is completed quickly and effectively, providing long-lasting protection for your vessel.
Zinc-Based Galvanising Products from Promain
Zinga Zingalu Spray - Silver-finish zinc and aluminium spray. A great all-rounder for hulls, fixings, and visible metal parts. Ready to use straight from the can.
Zinga Aluspray - Blended zinc and aluminium for a clean surface finish. Ideal when appearance and corrosion resistance both matter.
Zinga Zingatarfree - Tar-free alternative for eco-sensitive applications. Delivers brilliant rust protection without solvent-heavy smell.
Zinga Zingaspray - High zinc content for high-risk areas. Works well for quick touch-ups or full panel sprays.
Galva Plus Zinc 2120 - Quick-drying spray in a compact can. Perfect to keep in the toolbox for small fixes or edge work.
Zinga Zingaceram HS - A heavy-duty high-solids zinc coating. Best used where constant splash or wetting occurs. Can be topcoated.
Fosroc Galvafroid - Brush-on zinc primer with excellent water and corrosion resistance. Often used as a base layer before applying other marine paints.
Which Cold Galvanising Product Should I Choose?
-
Sprays: Easy for fast touch-ups or where tools can’t reach
-
Brush-on tins: Best for large areas, structural steel, or priming
-
Aluminium blends: Choose these for visible areas with a neater finish
-
High-solids types: Ideal for intense saltwater or industrial use
If unsure, contact our support team - we’ll help you find the best fit for your boat.
How to Maintain Galvanised Coatings
-
Wipe down occasionally to remove salt build-up
-
Re-apply zinc spray if you notice any exposed metal
-
Avoid dragging chains or anchors over treated surfaces
-
Store leftover paint in a dry place for later use
-
Keep a can onboard for quick maintenance when at sea
Cold Galvanising Around the Waterline
The waterline is a high-risk area where paint breaks down quickly due to constant moisture and marine organisms. Zinc coatings resist this damage and stop rust from forming beneath surface paints.
Before applying your antifoul, a cold galvanising primer creates a stable base and reduces future paint failures.
Cold Galvanising for Boat Trailers
Don’t forget your trailer. These are often neglected but just as exposed to water, salt and wear. Galvanising your trailer helps stop rust from spreading through bolts, frame joints, and axles.
Quick sprays like Zinga Zingalu or Galva Plus Zinc are ideal for these touch areas.
Works Well With Other Marine Coatings
Zinc primers can be overcoated with:
-
Gloss or enamel topcoats
-
Black tar varnish
-
Undercoats and bilge paints
-
Most solvent-based marine paints
Always check the compatibility of your finish before applying over zinc.
Can I Paint Over Cold Galvanising?
Yes - but only after it’s fully cured. Some coatings require a light key or etch to allow marine topcoats to grip. If you plan to antifoul, you can still start with zinc protection to stop corrosion beneath the paint film.
Cold Galvanising is a Smart Investment
Steel replacement or hull welding is expensive. Cold galvanising is an easy way to add value to your boat and extend its life. It costs far less than full repairs and delivers peace of mind—especially in salt-heavy or brackish water environments.
Common Misconceptions
“It’s just another paint.” - False. It’s a reactive barrier, not a decorative coat.
“It’ll wash off.” - Not when applied correctly - zinc chemically bonds to the surface.
“It only works on new boats.” - Wrong again. It’s just as effective on older hulls and parts as long as they’re clean.
Ready to Order?
Promain stocks a variety of zinc-rich marine coatings at competitive prices. We deliver direct and offer expert advice for all boat projects - big or small.
Order online today or contact us for help choosing the right cold galvanising paint for your boat.
FAQs:
Is cold galvanising any good?
Yes. It’s widely used on marine equipment because it delivers long-term protection from corrosion with minimal effort.
How long does cold galvanising last?
With good prep and maintenance, over 10 years - especially if topcoated.
Can I spray cold galv over rust?
You’ll need to remove loose rust first. Zinc needs a clean, stable surface to bond properly.
What are the disadvantages of cold galvanising?
It doesn’t leave a shiny finish and sometimes needs reapplication. It's not suitable for use over oily or flaking surfaces.