Triggers for Vanilla Blocks (Specifically Fire)

Currently trying to develop a mod that changes how fire behaves- specifically, so that fire will generate ash layers and charred blocks when burning wood. This would be relatively easy if there were a way to use the same triggers as modded blocks on Vanilla blocks- however, since I can't find an easy way to do this, the only solution I've come up with is to remove existing fire from the game, and add a custom fire that behaves in a similar manner, plus the modded effects. (...Which is a pain, but not entirely undoable.)

...If anyone has any ideas for a simpler solution, I'd love to hear 'em!