Water damaged windowsill (bathroom)

[Aco]

Hi,

We have a water damaged windowsill in the bathroom (internal).

The paint was bubbling in places so I have scraped and sanded down.

I'm not sure what exact material the windowsill is but having sanded down the water damaged area, the wood, although dry feels soft/flaky.

My question is, do I need to apply anything to exposed area of the windowsil before painting?

Thanks

Aco

 

[Robbie uk]

Looks like it could be an MDF sill. I would give it a coat of oil based undercoat to start with and flat back on top of that prior to putting anything else on it.