Primer for filler

[Jupiter01]

I have filled my walls in various places and read that I should prime this before I apply the emulsion coats. This should avoid "filler grinning" amongst delivering other benefits.
Which product do you recommend? Ideally something that I can purchase at toolstation or screwfix please.

 

[misterhelpful]

You generally don't need fancy primers for typical filler repairs. A light coat or two of diluted emulsion (the same as you plan to use for the finish) is fine to use over the filler as the primer, in order to prevent 'grinning'. However, the filler does need to be level and well blended into the surrounding area, otherwise no type of paint will prevent the areas from being seen. Remember that matt emulsion also helps hide blemishes far better than other finishes.

If you really feel the need to prime with something else, I would go with BullsEye 1-2-3, but you will probably find that this type of primer will still flash through your first coat of emulsion.