Update Nov 13, 2021:
The epoxi treatment we did in 2020 failed due to a series of unknown events and had to be redone in 2021. This post about how we applied the Coppercoat still applies and contains some good tips if you are to do this yourself. If you are doing an epoxi treatment, or just have a general curiosity for boat stuff, we really recommend that you read our summary about the epoxi failure and what we learned, described here. Since we now have applied Coppercoat twice, this post has been updated to add some additional tips (italic notes).
The waiting time and time frames described in this post correspond to the instructions given for the specific barrier coat we painted with the first time. When we did the Coppercoat the second time, over the new epoxi which works in a different way, the time frames changes. If you are about to apply Coppercoat to your own boat, talk to Coppercoat directly! They are great and will help you get your the right waiting times and time frames for your project.
Coppercoat is applied by painting several coats wet on tacky. How much Coppercoat that is needed is calculated depending on hull shape, width and length of the boat and draft. Depending on how thick you make each layer the paint will be enough for 4-6 coats. For our 40 foot we ordered 11 liters of Coppercoat and saved one of them for the rudder, under the keel and the 4 patches under the stands (which were painted later).
The plan was to have 4 people painting at the same time so that’s what we ordered rollers and roller shafts for. In the end that was not really how we best did it, so we changed and ended up being 2 people painting with the normal size rollers (20 cm) and 2 people holding the trays and alternating painting with a smaller roller (10 cm) in the tight and tricky places. This last part is not something that is described in any of the guides we found but something we really think made it easier. Having someone holding the trays and stirring the paint in it from time to time made the application less stressful and more even. Also, buying a few smaller rollers that could reach the tricky parts (like inside the bow thruster tunnel, around the keel and thru hulls) made the application in these spots a lot easier. We also used a painting brush to push some paint into and around the thru hulls.
Update Nov 13, 2021:
In 2021, when we did the application again, we could not get hold of the same rollers as used the first time. Instead we got a tip to use thin, but long, ultra fine mohair rollers (15 cm) for the entire application which we think actually worked out much better. First of all, they were not as heavy to paint with, and secondly there was less waste product left in each roller when throwing them away. Even though it is pretty hard to say, it also felt like it resulted in a smoother surface.