Using a water based satinwood directly over a water matt emulsion

[jbl11]

Hello all,
I'm a complete novice at painting, but want to give our interior wooden doors a coat of paint.
The original paint is a water based satinwood brilliant white (Dulux diamond white).
Over the years this has had patches of a water based vinyl matt emulsion to cover things up over the years - it looks very patchy and messy.
Now, I really want to keep this as simple as possible. Am I going to be able to just apply the Dulux diamond white as an extra coat? Will it cover the patches of emulsion effectively, or will it start flaking or peeling?
Or will I really need to sand it down? If so, where will I go from there?
Thanks for any advice

 

[joe-90]

Ideally you would give it a sand until it was smooth and the emulsion was gone, then a coat of say Leyland Acrylic Primer/undercoat, then a couple of top coats, but you'd probably get away with just the new top coats ofter sanding.

 

[jbl11]

Thanks I will sand and then just stick with the top coats, and hopefully get away with it.

 

[foxhole]

I used Dulux diamond white on entire property, wished I hadn't, very poor results [and very expensive] and had to redo the lot with gloss.