Patchy Dulux Light and Space

[Sundaypainting]

I have just painted (with a brush) our utility using Dulux Light and Space matt emulsion and after three coats the end result is still rather patchy. They are plastered walls that had previously been painted with what appeared to be a matt emulsion of a different colour . The problem is not the old colour showing through, rather it is just a generally patchy appearance. I am not a novice home-decorator and have not encountered this before. My query is in two parts - why has this happened and what should I do now? Thanks for any guidance.

 

[Wayners]

Emulsions aren't what they were as chemical regulations have changed and will continue to change.
15+ years ago exstenders were taken out so paint don't settle and keep a wet edge like it did.
To get around this you need to prep surface and possibly seal. You also need to have good technique.

You are better off rolling surface and if you don't like the roller finish then roll to apply paint and use a large brush to tip off the surface

 

[Sundaypainting]

Thanks for that. What paint would you recommend to go over the Light and Space? Is Floetrol a useful addition or a nono. Thanks again.

 

[Wayners]

Light and space has particles to reflect light if memory servers.
I've used it many years ago.
Couldn't see any benefit vs standard emulsion.
You can add Floetrol. I've used it but more for spraying.
I don't know if it will help