Paint boat topsides above the waterline

Guided shopping manual

Guide to painting boat topsides above the waterline

Boat topsides above the waterline need careful cleaning, fair sanding, primer where needed and a smooth polyurethane finish that suits visible exterior panels.

What do you need to paint boat topsides above the waterline?

Cleaning and degreasing

Mipa silicone remover in liquid or spray format removes grease, silicone and wax before sanding, priming or coating.

Surface keying

MP Hand Block Soft or MP Sanding Sponge helps dull glossy areas and keep curved edges even before primer or topcoat.

Epoxy primer for mixed substrates

Mipa EP 100-20 is the epoxy primer method for steel, zinc-coated steel, aluminium, fibreglass and mineral substrates before the finishing coat.

Gloss polyurethane finish

Mipa PU 250-90 gives a glossy 2K polyurethane finish for above-water panels, with the matching hardener and 2K thinner used in the same coating stage.

Small area spray finish

Mipa Mix PU 250 2K Paint Spray 48+ is the compact spray option for smaller topside pieces or localized above-water colour work.

How to paint boat topsides above the waterline

  1. 1
    Clean before sanding

    Remove wax, grease, silicone and sanding residue so the primer or topcoat can bond to the actual surface.

  2. 2
    Sand evenly

    Dull the old finish or prepared substrate without cutting uneven low spots into visible topside panels.

  3. 3
    Prime where the surface needs it

    Use the epoxy primer method on exposed fibreglass, aluminium, steel or mixed substrates before the topcoat.

  4. 4
    Apply the polyurethane finish

    Use the gloss PU finish for the main topside coating and keep each coat even from edge to edge.

  5. 5
    Let the coating cure

    Keep the fresh finish away from early abrasion, polish, washing and heavy handling until it has cured enough for service.

Which topside paint format should you choose?

For full panels

Choose the liquid PU topcoat system when a larger topside area needs an even film and controlled application.

For smaller parts

Choose the 2K spray method for small removable sections or localized topside pieces where spray-can handling is practical.

For mixed substrates

Choose the epoxy primer step when the work includes exposed fibreglass, aluminium, steel or repaired areas.

Technical details

  • Mipa PU 250-90 is a gloss 2K PU topcoat with long open time and suitability for brush and roller application.
  • Mipa EP 100-20 is the primer method for steel, zinced steel, aluminium, fibreglass and mineral substrates.
  • Mipa PUR Plus Hardener A60 and Mipa EP 950-25 hardener are not interchangeable because they are used in different coating stages.
  • This guide is for above-waterline topside work, not antifouling or constant underwater coating.
Practical suggestion

Paint long visible sides in manageable sections and keep a wet edge, because uneven starts and stops are much easier to notice on glossy topsides.

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