How Much Antifouling Do I Need?

How much antifouling paint do I need?

Work out the area to be painted using the appropriate calculation (below).

Divide the area by the coverage of the paint you’ve chosen to determine how many litres per coat you will need. All FLAG product datasheets are available here.

Multiply the litres per coat by the number of coats to give your total paint requirement. Please take care when considering how much paint you need. All paint manufacturers state coverage as a theoretical rate. Surfaces will have different profiles/textures and porosity levels. Also some wastage should be expected. Practical spreading rates can often be a bit lower than the theoretical rates.

It’s highly recommended to give an extra coat of antifouling to all leading and trailing edges and other high turbulence areas as these areas can wear faster.

To calculate the number of square meters that will be painted, the following measurements are required: LWL = Waterline Length; B = Beam; D= Draft

For a Fin Keeled Craft (see image 1) the underwater Area = 0.50 x LWL x (B + D) sq.m

For a Medium Draft Craft (see image 2) the underwater Area = 0.75 x LWL x (B + D) sq.m

For a Full Keeled Craft (see image 3) the underwater area = LWL x (B + D) sq.m

Please see below for images showing different craft types:

IMAGE 1 - Fin Keeled Craft

IMAGE 2 - Medium Draft Craft

IMAGE 3 - Full Bodied Craft