The key points first:

F2 EcoHull is a dedicated fouling-release system – not a classic antifouling coat. Built up correctly, you get a very smooth, robust surface that is easy to clean, lets your boat glide through the water more easily (fuel savings) and reliably protects against fouling over many seasons.

Application is well within reach for DIY owners too, as long as you follow the instructions exactly. Deviations can lead to poor adhesion or delamination.

The system at a glance

F2 EcoHull is suitable for hulls made of GRP, carbon, aluminium, steel and wood – and can be used across the entire underwater hull: hull, saildrive, rudder, through-hulls and trim tabs. In short: everything below the waterline except the propeller and shaft. For those there is F2 OptiProp – developed specifically for rotating parts.

Product	What it does
F2 Degreasing Solution	Solvent-free cleaning of the substrate before painting – prevents adhesion problems caused by grease and residue.
F2 EcoPrimer	Two-component epoxy resin. Seals the old substrate and acts as a bonding primer when switching from existing antifouling to F2 EcoHull Scenario A only – see below
F2 EcoHull Adhesive Coat	1K hybrid polymer. Bonds the substrate to the Top Coat, gives the system its colour base and forms the robust foundation for the fouling-release effect.
F2 EcoHull Top Coat	1K hybrid polymer. Forms a high-gloss, ultra-smooth, water-repellent surface that makes it extremely hard for fouling to settle (fouling-release). The Top Coat is transparent - with or without sparkle effect. Sparkle tip Choose the Top Coat with sparkle effect. As you apply it, you immediately see where material is still missing. The gloss Top Coat (without sparkle effect) gives no film-thickness indication and is therefore harder to apply – not recommended for DIY.

How many coats?

From each F2 product you generally apply only one coat, i.e. one layer each of EcoPrimer, Adhesive Coat and Top Coat. Unlike classic antifouling, you don't build up multiple layers.

Typical sequence – how many days do you need?

Day	What happens
Day 1	Preparation & sanding (Step 1)
Day 2	Cleaning + applying primer (Steps 3–4)
Day 3	Apply Adhesive Coat + Top Coat (Steps 5–6)
Day 4	Waiting time – min. 36 hours before craning/trailering/re-blocking
Day 5	Lift/re-block + touch up stand areas (Steps 7–8)
From Day 5	Launching possible once Top Coat is touch-dry (Step 9)

Flexible scheduling

The steps don't have to happen on consecutive days – with one important exception: the F2 EcoPrimer must be over-coated with the Adhesive Coat within 24 hours, otherwise the area has to be sanded and cleaned again. The Adhesive Coat and Top Coat, by contrast, have no maximum recoat interval – here you can pause for several days, as long as the surface stays clean, dry and dust-free. More on this in → Step 1.

What you need – checklist

F2 EcoHull Kit

F2 EcoPrimer BASE + ACTIVATOR Scenario A only – see below
F2 EcoHull Adhesive Coat
F2 EcoHull Top Coat
F2 Degreasing Solution

Calculate the right kit size for your boat

The amount you need depends on your boat's hull area. Our surface calculator works it out in seconds – and shows you straight away which kit fits. Surface calculator →

Keep the cans closed

Only open the cans when you start applying – not before. After filling the paint tray, close the can again right away. Use opened cans within 5 days. Unopened, the products keep for 12 months.

Tools & materials

Random orbital sander + sandpaper P60–P80 and P180–P220
Mixing paddle for a cordless drill For Adhesive and Top Coat
Mixing cup with measurement markings For F2 EcoPrimer only
enough paint trays
high-quality foam rollers no long-pile rollers
Small brushes for edges and corners
High-quality masking tape
Clean sponges, cloths and/or a brush
Bucket For water during the cleaning step
Personal protective equipment

Application set

Rollers, paint trays and other accessories are available directly as the F2 Application Set →

Clean tools immediately

Foam rollers, brushes and paint trays cannot be reused. Wipe other tools with a paper towel right after use – while the coating is still wet. If necessary, wipe with acetone, but take care: acetone residue can impair adhesion. Once cured, the coating can no longer be dissolved – then only scraping it off will work.

Step 1

Surface preparation

Surface preparation is the most important step of the whole job. The coating is only as good as the substrate beneath it. A poor substrate leads to delamination, flaking and blistering, and unevenness can reduce performance. If you want a result that lasts 5+ years, don't cut corners here.

Which scenario applies to you?

Old antifouling present: Scenario A. Bare or new hull: Scenario B.

Scenario A – hull has old antifouling on it

You need: F2 EcoPrimer

You are in Scenario A if your hull currently has an old antifouling coat and you are not planning a complete rebuild of your underwater hull, but want to build on the existing coat. In that case the F2 EcoPrimer is required as a conversion layer. It seals the prepared substrate and acts as a bonding primer between the old coat and the F2 EcoHull Adhesive Coat.

1 Assessment

First get an overview of the current condition of your underwater hull. How firmly does the old coat adhere, are there damp, loose, soft, rusty or brittle spots, and is silicone or Teflon involved? That determines how much has to come off.

2 Remove loose layers

All damp, loose, soft, rusty or brittle material must be removed down to a sound, smooth, clean and dry substrate, by sanding, sand- or ice-blasting or stripping. Coatings based on silicone or Teflon must be removed completely.

Recommendation

Old antifouling coats should be removed as completely as possible, down to the barrier coat beneath. The cleaner the base, the better and more durable the adhesion of F2 EcoHull.

Special case: Coppercoat

Sand until the green oxidation layer is completely removed, the rest can stay. Then clean and carry on with F2 EcoPrimer.

3 Fine sanding

Finish with the random orbital sander at P180–P220 to an evenly matt, smooth substrate. Work corners and hard-to-reach spots by hand.

4 Continue to Step 2

Surface preparation for Scenario A is complete. You can skip Scenario B and continue directly. Continue to Step 2 →

Scenario B – hull without a base coat – new or fully sanded back

You need: several coats of barrier

You are in Scenario B if your hull is bare, i.e. new or sanded all the way back to the substrate. Here you don't need the F2 EcoPrimer, but first a separate epoxy barrier coat.

F2 EcoHull is not an adequate barrier coat

F2 EcoHull is a fouling-release system, not a barrier against osmosis or corrosion. The F2 EcoHull Adhesive Coat is applied directly onto a fresh, suitable epoxy barrier coat; the F2 EcoPrimer is not used.

1 Choose and apply a suitable barrier coat

Choose a 2K epoxy primer suitable for your substrate. Usually 3 to 5 coats are needed; the exact number and film thickness follow the primer's data sheet. This builds up an adequate barrier.

Match the primer colour to the F2 colour

The F2 EcoHull Adhesive Coat covers well, but not completely over high-contrast substrates. So match the colour of the final primer coat to your F2 colour:

Black Gloss / Sparkle Graphite	→	dark grey to black primer
Royal Blue / Blue Sparkle	→	blue or dark grey primer
White Gloss / White Sparkle	→	white or very light primer

2 Prepare for the next coat

How to proceed depends on the primer type. First check your primer's data sheet: is there a VOC figure?

	Solvent-free	Solvent-based
How to identify	No VOC note on the data sheet	VOC figure on the data sheet
Waiting time	Until the last primer coat is touch-dry, then continue within 24 hours straight on with the Adhesive Coat	At least 7 days of off-gassing at 20 °C so all solvents can escape
Sanding?	Not necessary, as long as you continue straight on with the Adhesive Coat within 24 hours	Always necessary: after 7 days, rinse the surface with water, then sand well
Window missed?	If more than 24 hours have passed, the surface has cured too far and must be sanded	–
Examples	Hempel High Protect II International Gelshield Plus	International Interprotect International Gelshield 200 International VC Tar2

3 Sanding (if needed)

Sand solvent-based primers with P180–P220 after 7 days of off-gassing before you continue. Solvent-free primers can be over-coated directly without intermediate sanding, as long as no more than 24 hours have passed (see table above).

4 Continue to Step 2

The barrier coat is built up and prepared. Continue with Step 2, the conditions.

Step 2

Check the conditions

Condition	Requirement
Air temperature	10 °C to 35 °C – during application and throughout the drying time.
Surface	At least 3 °C above the dew point Watch out for condensation A common issue, especially in spring: a cool surface + damp morning air = the hull „sweats". You can barely see it – but the coating will not bond to a condensation-covered surface. Test: run the back of your hand over the hull. Cool and damp? Wait – usually until midday.
Humidity	Max. 90% – no rain on fresh primer (otherwise sanding is required). On the Adhesive Coat and Top Coat, rain after about 4 hours is no problem. The surface must be dry before you continue painting!
Work area	Do not sand, polish or saw nearby – dust and particles can impair adhesion. Underwater hull first, then polishing Deal with the underwater hull before polishing. Invisible polish particles spread across the whole hull and can impair adhesion. If polishing was done first – clean extra thoroughly!

Final check before painting

The substrate must be sound, smooth, clean and dry. Moisture trapped under the coating will lead to adhesion problems. If in doubt, check with a moisture meter.

Step 3

Cleaning with F2 Degreasing Solution

Grease, dirt and residue on the substrate are the most common cause of adhesion problems. The F2 Degreasing Solution is a solvent-free cleaner that prepares the substrate optimally before painting. This step matters more than it looks.

Cleaning the substrate with F2 Degreasing Solution

1 Lightly dampen the hull

Spray the whole hull with fresh water.

2 Dilute the F2 Degreasing Solution

Mix 1:10 with fresh water, i.e. one part cleaner to ten parts water.

3 Clean the hull

Wipe down the whole hull with a soft sponge or brush. If you pick up the loosened dirt with a cloth, always wipe in one direction only, never back and forth, otherwise you spread it again.

4 Repeat if needed

If heavily soiled, clean a second time.

5 Rinse thoroughly

Rinse with clean fresh water until no cleaner residue remains on the hull.

6 Let it dry completely

Only paint once the hull is completely dry. Residual moisture under the coating impairs adhesion.

No acetone, no nitro thinners

Never use conventional solvents for cleaning. They leave invisible residues that permanently interfere with adhesion.

Step 4

Apply F2 EcoPrimer Scenario A only

When do you need the F2 EcoPrimer?

You need the F2 EcoPrimer whenever you have sanded down or off your old antifouling but have not applied a new epoxy primer. If a fresh epoxy primer has been applied, you can skip this step. In that case, see the notes under Step 1 – Scenario B.

Mind the pot life

The F2 EcoPrimer consists of two components: BASE and ACTIVATOR. Once BASE and ACTIVATOR are mixed, the clock is running: the working time is a maximum of 30 minutes at 20 °C. The warmer it is, the shorter it gets. Keep cans in the shade, and in very warm conditions stand them briefly in a cool water bath first.

Recommendation: mix max. 250 ml per person at a time!

Mixing EcoPrimer

4A – Mixing

1 Pre-stir the BASE

Open the BASE can and mix the contents thoroughly by hand.

2 Measure out BASE and ACTIVATOR

In the separate mixing cup, measure by volume at a 60:40 ratio, read off the cup's markings. Example: fill BASE to the 150 ml mark, then top up with ACTIVATOR to the 250 ml mark, i.e. a quarter litre. Never mix directly in the can, always use a separate mixing cup. Do not thin.

3 Stir homogeneous by hand

Stir by hand with a stir stick until the mix is completely even. Not with a cordless drill, which introduces too much heat and air. Heat shortens the already short pot life, air causes bubbles in the coating.

4 Apply immediately

Pour into the paint tray and apply straight away. The pot life of max. 30 minutes at 20 degrees runs from the moment of mixing.

Fire risk

Mixed 2K systems generate their own heat as they cure. Larger leftover quantities of F2 EcoPrimer can develop extreme heat. Never leave a cup of leftover material unattended on a flammable surface.

4B – Application

1 Apply in cross-coat

Apply the primer with the foam roller in a thin, even coat. First roll vertically top to bottom, then, without picking up fresh paint, go over it horizontally right to left. This spreads the paint evenly and removes streaks.

Cross-coat technique

2 The right amount

One litre covers about 10 m². That gives a thin, even coat of around 100 microns.

Opacity

The primer does not cover 100% – that is normal. Its job is adhesion, not colour. Full coverage comes with the Adhesive Coat.

3 Work edges and corners

Touch up spots the roller can't reach with a small brush.

Waiting time
Minimum before Adhesive Coat	4–6 hours (touch-dry)
Maximum	24 hours
Waited longer than 24 hours?	Wash the surface, then sand thoroughly with P180–220. Then clean once more with F2 Degreasing Solution (Step 3) – only then apply the Adhesive Coat (Step 5).

Step 5

Apply the Adhesive Coat

The Adhesive Coat is the colour-giving coat. The entire colour of your underwater hull comes from the Adhesive Coat. The Top Coat that follows is transparent and does not change the colour. That is why the Adhesive Coat needs an even, covering coat. As a one-component hybrid polymer it bonds the substrate to the Top Coat and forms the robust foundation for the fouling-release effect.

Allow enough time

The Adhesive Coat is very viscous – noticeably thicker than ordinary paint. That is normal and intended. Allow more time than for a conventional antifouling coat, because the polymer has to be rolled out carefully and with light pressure evenly across the surface. That takes a bit of patience!

1 Open the can and stir the paint thoroughly

Stir mechanically with the mixing paddle, by hand is not enough here. The pigments settle to the bottom quickly, so mix thoroughly from the bottom up for at least 2 minutes until the paint is even. Do not thin.

2 Pour into the tray and close the can again

After filling the paint tray, close the can again right away. The hybrid polymer reacts with humidity; left open it skins over.

3 Apply one coat in cross-coat

One coat of Adhesive Coat with the foam roller. First roll vertically top to bottom, then, without picking up fresh paint, go over it horizontally right to left. This spreads the paint evenly and removes streaks.

Cross-coat technique

4 Don't apply too thick at once

If the material is rolled on too thick, it won't level out smoothly but pulls ripples as it dries, so-called „orange peel". If opacity isn't sufficient after the first pass, a second coat can be applied after 4 to 6 hours. Coverage about 10 m² per litre, that equals a film thickness of around 100 microns.

5 Leave the stand edges free

Leave approx. 5 cm clearance around each boat stand, so that after re-blocking each coat can be finished overlapping into itself (Step 8).

Stand area

Waiting time
Minimum before Top Coat	4 hours (touch-dry)
Maximum	No maximum – as long as it stays clean, dry and dust-free

Rain after the Adhesive Coat

Rain after at least 4 hours is usually no problem. If dirt marks remain: clean with fresh water and let dry before applying the Top Coat.

Step 6

Apply the Top Coat

The Top Coat is the final coat and gives the system its function. As a one-component hybrid polymer it forms the high-gloss, ultra-smooth, water-repellent surface that fouling can barely settle on, the fouling-release effect. It is transparent, with or without sparkle effect. The colour comes from the Adhesive Coat.

1 Open the can and stir the paint thoroughly

Stir mechanically with the mixing paddle. If you have the sparkle variant, stirring distributes the effect evenly. Do not thin.

2 Pour into the tray and close the can again

After filling the paint tray, close the can again right away. The hybrid polymer reacts with humidity; left open it skins over.

3 Apply one coat in cross-coat

One coat of Top Coat with the foam roller. First roll vertically top to bottom, then, without picking up fresh paint, go over it horizontally right to left, just like the Adhesive Coat. This makes the coat even and removes streaks.

4 Don't apply too thin

The Top Coat rolls on much more easily than the Adhesive Coat. That tempts you to apply it thinner. But this is the final protective and functional coat, so deliberately apply the same amount of material as the Adhesive Coat, don't leave any over, spread it all. If you chose the Top Coat with sparkle, you see immediately while applying where material is still missing. That helps you apply evenly and not too thin.

5 Smooth out runs and drips immediately

While wet they're easy to correct, once they start to dry they're not.

6 Leave the stand edges free

Again approx. 5 cm around each boat stand, just like the Adhesive Coat, for the later touch-up after re-blocking (Step 8).

7 Pull off the masking tape right after applying

While the Top Coat is still wet, pull off the masking tape. This gives a clean edge without tearing.

Top Coat applied with sparkle effect

Waiting time
Minimum before craning	36 hours
Maximum	No maximum No time pressure – tackiness is normal The boat can stay ashore indefinitely after the Top Coat – there is no maximum standing time. The Top Coat does stay tacky: that is by design, not a fault. Full curing only happens in the water. Once touch-dry (~4–6 hours), the surface can be lightly dampened with fresh water – this speeds up curing.

Stand area – different from normal antifouling!

The areas under the boat stands cannot simply be touched up while hanging in the lift. The coating build-up and drying times normally require re-blocking.

Step 7

Re-blocking / Craning / Trailering

In this step the boat is re-blocked or set up anew, so that the areas under the boat stands become free and can be coated in Step 8. These spots usually can't be touched up while hanging in the lift; coating build-up and drying times normally require re-blocking. Because the finished surface is extremely smooth, a few precautions are needed when craning.

Slip hazard

Because the surface is extremely smooth, there is a risk that the lifting slings slide on the hull or slip apart. Simple precautions prevent this. You'll find guidance in our article on lifting →

Applies to trailering too

The notes about the smooth surface apply just the same when trailering: keep supports and straps clean, protect the fresh coating with soft padding, and make sure everything sits securely without slipping.

After applying the Top Coat, wait at least 36 hours before the boat is loaded, whether crane or trailer. The coating must be pressure-resistant enough to carry the boat's weight.
Tell the lift operator about the extremely smooth surface.
Ask the lift operator to tie the slings together under the hull with a line (secure them) to stop them sliding apart.
Make sure the lifting slings are clean.
If needed, use soft padding (e.g. painter's fleece) between sling and hull to protect the fresh surface. Especially important on chines.

Craning the boat

Step 8

Touch up the stand areas

Once the boat has been re-blocked and the stand contact areas are exposed, you touch up these spots. Essentially you repeat the full build-up as on the rest of the hull, just on a small area and according to your scenario from Step 1.

1 Sand the exposed area

P180–P220, so the following build-up adheres well. If there is a barrier coat on the hull (Scenario B), the substrate preparation follows its data sheet, just like in Step 1.

2 Clean with F2 Degreasing Solution (1:10) and let dry completely

Only continue once the area is completely dry. Residual moisture impairs adhesion.

3 Apply the primer

Scenario A (F2 EcoPrimer): apply EcoPrimer. Overlap onto the 5 cm edges left free in Step 5. Mixing, application and waiting times exactly as in Step 4.

Scenario B (new barrier primer): re-do the barrier coat on the exposed area. Overlap onto the 5 cm edges left free in Step 5. Substrate preparation, number of coats and waiting times per data sheet, just like in Step 1. EcoPrimer is not used here.

4 Apply the Adhesive Coat

Application as in Step 5. Overlap onto the 5 cm edges left free in Step 6. Then wait around 4 hours until touch-dry.

5 Apply the Top Coat

Application as in Step 6. Overlap generously, so the seam disappears completely.

Step 9

Launching & Curing

Launching

Launching is possible as soon as the Top Coat of the stand touch-up is touch-dry (around 4–6 hours). The rest of the hull is long past the 36 hours from Step 7 by then. For the small touched-up areas there is no separate 36-hour wait, as long as no sling pressure acts on them.

When craning in

The surface is still extremely smooth. The same precautions as in Step 7 apply to all crane movements: secure the slings, keep them clean and protect fresh spots with soft padding.

Longer time ashore

The boat can stay ashore indefinitely before launching. It does not have to go in the water within any set time. The coating stays slightly tacky, because full curing only begins in the water.

Phase
Ashore after application	Touch-dry, but still slightly tacky
First 8–12 weeks in the water	Continuous chemical curing. During this phase the coating does not yet deliver 100% fouling-release performance
After 8–12 weeks	Fully cured – full fouling-release performance

Step 10

Care & Cleaning

After the first 8–12 weeks in the water, a gentle clean with a soft sponge or soft brush is recommended (Early Clean). This removes the initial biofilm and lets the fouling-release system reach its full performance.

Never use

Never use hard brushes, scouring pads (Scotch-Brite) or aggressive chemicals for cleaning. The surface is designed to be self-cleaning – gently wiping with a soft brush or sponge is usually enough to remove fouling.

Pressure washing

Possible – but only after the first 8–12 weeks in the water, once the coating is fully cured. In the first weeks, clean only with a soft sponge or brush. After that: keep enough distance, use only as much pressure as necessary.

Applying F2 EcoHull – Step-by-Step Guide