Which primer do I use under limewash paint?

no idea what you are trying to achieve as you are trying to use products that do the complete opposite of each other which will most likely result in complete failure, if you have already plastered with modern plaster, mist coated & painted it stick with that, white wash is generally used on its own applied straight to the lime plaster in at least tree coats as its breathable the products you have used are not. good luck Alex

Limewash paint adheres best to porous surfaces. Given that you've already applied a mist coat and a coat of Dulux emulsion paint, it might hinder the absorption of the limewash into the plaster. For the best results when using limewash over previously painted surfaces: Clean the Surface: Ensure the wall is free from any dirt, dust, or grease. Use a Mineral-based Primer: Before applying limewash on previously painted walls, it's a good idea to use a mineral-based primer. This will help to provide a porous surface for the limewash to bond to. Romabio's BioGrip Micro or similar products are specially formulated for such purposes. Test Patch: Always do a test patch to see how the limewash adheres and looks over the primer and existing paint. Multiple Coats: Remember that limewash may require multiple thin coats to achieve the desired look. Allow each coat to dry (typically 12-24 hours) before applying the next. Protection: Once you have achieved the desired effect with your limewash, consider sealing it with a lime-compatible sealer if you desire added protection, especially in high-traffic or high-moisture areas. Remember, while online research is useful, consulting with a local professional or paint store can provide insights specific to your region's climate and your home's unique needs. Good luck with your project!

If you are not applying to non-sealed masonry, wood, or plaster, you will need to apply Lime-Prep Primer to create a compatible surface for the limewash to grab onto. In addition to providing better adhesion, Lime-Prep primer will also help with producing a more accurate color finish.

I have to ask, why would you even want to use Limewash? As Alex (top) has already quite correctly stated, you've physically done what a newly plastered wall requires anyway (mist, top coat) so why on earth would you want to then Limewash it??!! That is bonkers - you are just creating more work for yourself which is utterly unnecessary. Not to mention that a Limewash works much much better on porous surfaces, allowing the wall to 'breathe.' Because you've mist coated and then top coated, you have completely negated the actual use/reason of a Limewash in the first place. The wall has been sealed (mist coat) so there's literally nothing for a Limewash to adhere to. It'll just sit there and run repeatedly down the wall. Besides all of this, Limewash is a dangerous substance and frankly you're far better off just staying away from it.