PU or epoxy: why the same ding costs different amounts
Polyester and epoxy boards are repaired with different materials and on different schedules. Here is why the price list shows two numbers.
The price list has two columns for most dings: one for PU and one for EPS/epoxy. The damage can look identical. The repair is not.
Two different boards
A traditional PU board is polyurethane foam glassed with polyester resin. An epoxy board is usually expanded polystyrene (EPS) foam glassed with epoxy resin. Polyester resin cannot touch EPS foam without dissolving it, so an epoxy board has to be repaired with epoxy from start to finish.
Why epoxy repairs cost more
- Materials. Epoxy resin costs more than polyester.
- Cure time. Polyester kicks off in minutes and can be sanded the same hour. Epoxy needs hours between steps, so one ding ties up the bench for longer.
- Water. EPS is an open-cell bead foam and pulls water in much deeper than PU. A ding that was surfed on often needs extra drying time and sometimes a bigger cut-out to reach dry foam.
How to tell which one you have
Many epoxy boards say so near the logo or the stringer. They also tend to feel lighter and more buoyant for their size. Inside an open ding, PU foam is fine and even, like a firm sponge cake. EPS looks like tiny white beads pressed together. If you are still not sure, send a photo and we will tell you.
What stays the same
Either way the goal is the same: dry foam, a watertight seal and a repair that is as strong as the board around it.