Osmosis Treatment

What is Osmosis Treatment?

When a yacht has had a previous painting or poor maintenance, it will have absorbed some chemicals that are potentially very corrosive to the hull paint and bonding agents no matter how high quality they are. Osmosis treatment is the process by which all of the bad stuff is removed from your boat’s hull. Osmosis Treatment can significantly reduce boat maintenance costs.

BowtoStern are experts in Osmosis treatments for boats and other marine vessels in the Hampshire area. Anywhere in the South Coast including Southampton, Hamble, Poole, Weymouth, Portsmouth, Gosport, Lymington, and Hythe, we can breathe new life into your vessel.

Get in touch today for a quick consultation. 

What Causes Osmosis on Boats?

Osmosis on boats is caused when water leaks into the boat and creates a barrier between the plywood and the gel coat. Once the sun is up and the boat is in motion, these minerals begin to evaporate and leave a salty brine to settle in crevices inside the boat. 

Over time, this can cause major damage to your boat, e.g the valves and prop shaft of an engine can be affected.

Call now to get a


07967 785590

Why Do You Need Osmosis Treatment for Your Boat?

Most boat owners know that keeping their hull clean is important. When a boat hull is left unattended, a greenish growth called algae may grow and cause the hull to become extremely hard to keep clean. 

Osmosis treatment means that we flush out the existing antifouling paint residue in your boat hull. Osmosis Treatment adds a protective layer of oxidized zinc to the surface of fibreglass or gel coat on your boat. This treatment can increase the useful life of your boat by preventing water from gaining access to and attacking the hull materials.

If you are looking for the best hands when it comes to Osmosis Treatment in the Hampshire area, you are on the right page. With years of experience making boats seaworthy, you can count on us to give you the results you desire.

Get in touch with Adam on 07967 785590 or 01489 784613 to talk about your needs.

Who We Are

BowtoStern Hampshire is a small, independent company specialising in all aspects of yacht maintenance and GRP repairs. We are based in the heart of Southampton. With years of experience in the boating industry, we offer our clients a professional service with a personal touch. 

We take great pride in our work and reputation for reliability. Our quality service has given us a loyal customer base who continue to use our services year after year.

Our Osmosis Analysis Process

BowToStern Osmosis Analysis Process is a revolutionary new technique for testing the condition of GRP hulls and deck structures using osmosis analysis. The process is non-destructive and identifies underwater blistering to detect the severity of the problem. 

Thorough analysis before proceeding with osmosis permits the maximum life expectancy from your osmotic repair and saves you money on repair cost and repairing product failure.

Our Osmosis Treatment Service

Our Osmosis Treatment Service for boats uses plant-based osmosis that is suitable for all your boat’s systems. The process is simple, efficient, and environmentally friendly. 

Your boat will be completely dry during the treatment so it requires very little downtime. This process is also ideal for larger vessels after they have been repainted or just before an upcoming season. Plus, it removes water spots, restoring the shine of your boat’s fibreglass finish. 

Let us beautify all available surfaces on your boat for a cleaner look and improved feel. Call us today!

Why Choose Us?

Competitive Price

With a yacht maintenance company like BowToStern, your boat osmosis treatment will not only be competitively priced but also completed quickly and efficiently by our highly trained service crews. 

Professional Team

BowToStern is a team of skilled professionals operating in Southampton. We understand the importance of seeking professional help for your vessel. Our dedicated team are passionate about our work and only offer high-quality care and professionalism to each and every customer we serve.

We take pride in our high standards of workmanship and quality control for all our projects, both industrial or private. 

23 Years of Experience

Adam has 23 years of experience in the boat repair business and leads a team of experts who are well-equipped and well-trained to carry out yacht repairs, maintenance, and structural work on all types of GRP yachts. 

Get in Touch Today

Are you in need of a fresh coat of GRP? Do you need some areas of your yacht cleaned? Is your antifoul failing? Have you got an osmosis problem on your hull..? We can fix it.

If you are looking for a team who are passionate about boating, treat your boat as if it were their own, and have years of experience in the industry then look no further than BowToStern.

We offer free quotes to all our customers.

Call us on 07967 785590 or 01489 784613 or send an email to [email protected]

Our Testimonials

“I wanted to write and thank BowToStern for their brilliant work in treating the osmosis damage on my boat. Their service went above and beyond what I had expected, after the first day, there was already a significant difference in the condition of the hull.”
“My yacht hull is now completely free of blisters and the thick gel coat has returned. Thanks to BowToStern for their Osmosis treatment restoration work on my IOR 40 yacht.”
“It's been almost 3 years since the osmosis treatment of my boat. I contacted BowToStern experts after seeing the impressive results on their website. They were really helpful and gave me some great advice, so I decided to book the treatment. I am really pleased with the results.”

Frequently Asked Questions

Osmosis on a boat isn’t just bad, it’s ugly. Osmosis will degrade the Gelcoat finish as well as the paint and fibreglass underneath the finish. The result is dull, rough, and pock-marked surfaces. Osmosis can cause a variety of blistering problems such as blistering of the Gelcoat, clear coat, and surface paint as well as blisters on the glass itself.

A barrier coat on a boat is a hard, smooth coating applied to the entire surface of the hull or topside. It is one component in a three-part system that includes paint, primer, and a sealer coat. The goal of this system is to provide an even and environmentally-friendly surface that prevents moisture/corrosion from destroying the boat’s structure.

Yes, we can paint over gel coats on a boat as long as you are willing to put up with the multiple coats of paint that typically need to be applied and the possibility that it might peel in the future. Speak to one of our team members on 07967 785590 or 01489 784613.

Boats have an air pressure difference between the inside and outside. When the hull cracks, it allows the water to enter inside. If you caulk every crack with silicone (or other material capable of being waterproof) then your boat will be protected against damage due to osmosis. 

Get a free quote. Call now 07967 785590