Restore a Faded GRP Hull

By admin Jan 21, 2026 0

How to Restore a Faded GRP Hull to a Shine (UK Small Boats)

UK small boats take a real battering from the elements. Saltwater, rain, UV exposure, and long winter lay-ups can quickly leave a GRP (glass reinforced plastic) hull looking dull and chalky. Whether you own a small fishing boat, RIB, speedboat, or trailer boat, most faded hulls can be restored with basic tools and a bit of effort.

Why GRP Hulls Fade in the UK

Saltwater exposure from coastal use
UV damage during summer months
Standing water and grime over winter
Lack of regular polishing or waxing

What You’ll Need

Boat shampoo or mild detergent
Soft brush or sponge
Cutting compound (medium to heavy cut)
Marine polish
Marine wax or UV sealant
Machine polisher (recommended for larger areas)
Microfibre cloths

Step 1: Wash Away Salt and Dirt

Start by thoroughly washing the hull. UK boats often carry a film of salt and grime that must be removed before polishing. Pay extra attention to the waterline and stern where deposits build up.

Step 2: Cut Back Oxidation

Oxidation appears as a chalky or faded surface. Apply cutting compound using a polishing machine or by hand. Work in small sections and keep the pad moving to avoid overheating the gelcoat.

Step 3: Polish to Restore Colour

Once the oxidation is removed, use a marine polish to bring back the gloss. This step restores depth of colour and removes fine marks left by the cutting compound.

Step 4: Wax and Protect

Finish with a good-quality marine wax or sealant. This is especially important in the UK, where frequent rain and salt spray can quickly undo your hard work.

How Often Should UK Boat Owners Do This?

Most small boats only need a full cut and polish every 1–2 years. Regular washing and a quick wax at the start and end of the season will keep the hull looking good for longer.