Can you use epoxy over water-based polyurethane?

We do not recommend applying epoxy over water-based polyurethane.

The epoxy can cause the water-based polyurethane to wrinkle or soften. Epoxy does not bond very well to water-based polyurethanes, so you might end up with fisheye blemishes (epoxy pushing away from the surface).

We recommend applying 2-3 coats of oil-based polyurethane over the water-based coating so that the epoxy will stick to it.

Note: It is best to test it out first on a small scale test to be safe.