Go to any chandlery or marine store and you’ll be faced with a multitude of marine sealants and caulking materials. Knowing what sealant to use for every sealing job on your boat is very important.

Essentially, every marine sealant is one of just three products – polysulfide, polyurethane or silicon.

Polysulfide is a synthetic rubber compound and is the “workhorse” of marine sealants.

Polyurethane is the sealant to use where you’re looking for a permanent seal. It’s an adhesive more than a sealant.

Silicone is a gasket material, not a sealant. Its adhesive properties are minimal and should be disregarded.

There is now a fourth product, a silicon/polyurethane hybrid that combines the adhesive properties of polyurethane with the gasket qualities of silicone.

To select the right sealant for your job, you need to answer just three questions.

Find out how to select the right marine sealant for your job here.

Filed under: Sailboat Maintenance