Osmosis treatment on a 10m Westerly Fulmar

Osmosis in boats in simplistic terms is the absorption of seawater by fiberglass (GRP). This can occur when bubbles have been left in the fibreglass at the time of lamination.

This 10m Westerly Fulmar was brought to us showing signs of blistering below the waterline.
After testing the moisture levels below the waterline we then go to work on peeling the existing gel coat off of the substrate. Once removed our normal process is to thoroughly steam clean this area to get rid of any impurities and residue which may have contributed to the osmosis.
The Hot Vac system is then applied to dry out the hull, these pads will be placed in various positions on the hull to maximise the drying process.

Osmosis blistering found on 10m GRP boat. Mylor Yacht Harbour, Cornwall    Osmosis Hot Vac system applied to a 10m boat in Mylor

Once the moisture levels are correct our GRP technicians then ‘fill and fair’ any imperfections in the hull before applying Hemple High Protect II Osmosis System which forms a hard, water resistant coating.

Osmosis Hemple High Protect II System applied to a 10m GRP boat in Mylor, Cornwall    Hemple High Protect II Osmosis System Application in Mylor Cornwall

After applying this treatment you can then apply antifoul or Coppercoat to the underwater section
The next stage in the process was to apply the Coppercoat, as chosen by the owner. Below the waterline was abraded, then an epoxy primer applied before the Coppercoat.

Osmosis treatment to 10m GRP boat at Mylor Yacht Harbour    Hemple High Protect II hull application Mylor harbour

Successfully treating osmosis on a boat is a detailed process which takes time and precision but if carried out correctly you shouldn’t have to treat it again.

To find out more about Osmosis treatment or Coppercoat for your boat, contact us for a chat and a free quotation. E: enquiries@mylor.com T: 01326 372 121.

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