How much should I invest in Antifoul?

The cost of antifoul ranges quite significantly depending on what your boat requires, but it should be considered an investment to protect your vessel. In the long term, higher quality antifoul can reduce growth on vessels leading to fuel savings and faster sailing.

  • Our most popular antifoul is Hempel Classic. Hempel Classic is an erodible antifoul which offers year-round protection. It is ideally designed for commercial vessels which are regularly used, reducing the chances for growth.
  • International Cruiser offers similar protection at this price point.
  • Hempel Tiger and International Cruiser 250 are both designed for slightly faster cruising boats up-to around 27 knots, this makes them a good option for motorboats and slower powerboats.
  • Hempel Hard Racing & International Ultra 300 are a perfect choice for vessels needing a little extra protection either because of their speed, or mooring. These ‘Hard’ antifouls have reduced wear meaning they will withstand 25 knots+ on the water and the daily rubbing of the seabed for vessels on a mud berth. These antifouls can also be scrubbed whilst in the water so are a favourite with racing yachts.
  • The top end of the antifoul market is Hempel Mille NCT, International Micron 300 & International Micron 350. These antifouls are perfect for cruising yachts, minimum drag over time means a sustained high cruising speed without have to stress about scrubbing the hull in the water.

Worker sanding down a boat ready for painting & antifouling.

What antifoul do I need for a tidal or mud berth?

We recommend a hard antifoul for boats which are on mud berths or are exposed to drying conditions. As the tide falls, the mud will slowly erode the antifoul from the hull of your boat. Using a hard antifoul reduces the impact of this and makes the antifoul last longer.

What antifoul do I need for a faster boat?

If your vessel is regularly doing more than 25 knots, it’s worth considering a hard antifoul. The friction of the water at higher speed can cause antifoul to erode more quickly thus leading to increased exposure on the hull and reduced performance.

Which Antifoul brand is the best?

Top antifoul brands include Hempel, International & SeaJet. All have an excellent reputation and offer a wide product portfolio.

What protection do I need to Antifoul my boat?

Paint covered hands

It is recommended to protect yourself and your clothing by using overalls, gloves, a face mask and eye protection.

How much antifoul do I need?

Most antifouls will cover around 13m² per litre and 2 coats is recommended. If your painting in warmer weather you’ll be able to recoat in 4 hours, for the cooler weather this extends to 8 hours.

  • Avoid antifouling in temperatures below 5°C as the paint will not cure properly.

How to prepare your Boat for Antifouling?

Following a thorough pressure wash, inspect your hull for signs of damage or any signs of concern.

  • If the previous paint looks in good condition use an abrasive pad (CRCS1002/1003/1005/1006/1286) over the surface. Make sure any dust is rinsed away or use a tack rag.
  • If you have some damaged areas of paint which require more attention, then:
  1. Apply an Epoxy filler (MARF1176/1153/1089/1087) for deeper damage or gelcoat filler/ (MARF1079/1090/1012/1047/1052/1172) for more shallow repairs.
  2. Use 80 grit production paper CRCS1439/1400/1217) to flatten the repair area before and after applying the filler, also be sure to use it on a block (CHTL1237) as this will give a flatter repair.
  3. The surrounding gelcoat will likely be compromised during the repair so a Hempel Light Epoxy Primer would be a good idea.
  4. Follow with Hempel Underwater Primer apply this whilst the epoxy primer is still soft (a good test is to put your thumb against the paint if it is soft and does not come off on your finger… it’s ready for Primer).
  5. Before painting you will need to mask the area just above the paint line. Make sure you use a good quality masking tape. This will reduce the chance of the paint bleeding under the tape and removal of the tape is easier. Cheaper tapes and leave residue on the hull needing hours of additional chemical cleaning.

Painting

A good roller is the ideal application tool. A smaller 4” roller (CRCS1091/1199/1341) is lighter to use and for painting under the hull. A longer handle (Long CRCS1122, Short CRCS1123) can save you having to crawl underneath the boat as regularly. Of course, a 7” roller (CRCS1121/1200) will get the job done quicker but is a bit heavier to use. Medium pile rollers apply a sufficient coat of paint for 60 - 70 microns wet.

  • Apply the paint thickly, inline with manufacturer guidelines. This is most effective and offer best protection.
  • Make sure the paint is stirred thoroughly (not just shaken)
  • Don’t paint your anodes!