Osmosis inspection

  • EMCI licensed
  • Professional and independent
  • Valid insurance reports

Safely traverse the waters!

Independent and custom inspections for recreational vessels.


EMCI Certified

Osmosis / moisture inspection

What is osmosis?

vlakdiktemetingIf you're planning on purchasing a vessel, it is important to know whether the hull of your boat is free of osmosis. Osmosis is a common phenomenon in which water penetrates the gel coating into the laminate of the vessel and mixes with other materials and acids. The mix of these substances creates pressure under the gel coating, potentially creating blisters and cracks. If the gel coating is damaged in such a way, the laminate will suck up water like a sponge.

Osmosis / moisture inspection

If you have a polyester boat or yacht, it is important to make sure it is free of osmosis. Osmosis can be regularly found in the lower hull of polyester vessels. If your current/future vessel is affected by osmosis, it is important to know the state of phase of the osmosis. This is crucial in determining any repair costs. It is therefore highly important to always conduct an osmosis inspection if you are planning on purchasing a new vessel.

You can also optionally include an osmosis inspection with your general boat inspection, or you may choose to have us conduct it separately.

Osmosis inspection by Boot-Check

Boot-Check uses a 'Tramex Skipper Plus' for all its moisture measurements. This device is a non-destructive moisture meter for detecting moisture in polyester (fiber) and wooden boats. The entire lower hull is inspected for blisters.

If osmosis is identified, this will be inspected further to determine what exactly is the cause and where the problem originates from in the laminate. The anti-fouling layer will have to be removed in a number of areas in order to determine the state of the gel coating. In addition, an osmosis inspection will always include a measurement of the amount of moisture in the laminate. If the laminate is moist, the ship has a high risk of developing real osmosis (blisters) in the near future. At the same time, a moist laminate does not necessarily have to lead to osmosis blisters (several other factors play a role). During an osmosis inspection we also assess the entire underwater hull. For example, we will inspect the underwater hull to determine if the laminate is still attached securely.