I can’t tell you how many times people ask me why they can’t do a faux finish over flat paint. So I would like to clarify and share with you why NEVER to use flat paint when doing ANY faux paint finish.
When doing most faux finishes you will use certain tools such as brush, rag, sponge, woolie, etc to manipulate the glaze color so that way the base color can show through. It is very important to have a smooth surface that allows the glaze to be movable.
Flat paint is much too porous. It would soak in the glaze and would not only dry quickly, but it would cause blotchiness in the finish.
If you have a wall that you would like to faux finish but has been painted with FLAT PAINT, then you will definitely need to re-paint with an eggshell, satin or pearl paint sheen.
Recently, I had a reader ask me if they could just use a clear coat over the flat paint and then do a faux finish on top of that, but really this is not a good idea. The flat paint and the clear coat can have an adverse reaction and possibly ruin the base paint. It is also much more expensive than regular paint. You might as well just re-paint with the correct paint and do the job right to start with.
So, for those of you who have considered doing a faux finish over flat paint – please think again. It will not work!
{ 1 comment… read it below or add one }
While what you say about flat paint being porous and the overpaint or glaze drying quicker is true, I frequently faux over flat paint for precisely that reason. If you know what you’re doing you can compensate for these characteristics. If you have uneven walls, either from age or poor construction – quite common in Arizona – then a flat base is a must to minimize the appearance of these imperfections. I also frequently use a watered down flat latex paint as a glaze rather than a glaze medium. This encourages the base paint to soak the glaze into the surface better. It eliminates the sheen caused by the use of a glaze medium so you retain a consistent flat (non-sheen) surface. I’ve found this particularly effective for applying aging finishes to adobe style houses and also good for minimizing the appearance of existing wall textures, like skip-trowelling, so you see the faux, not the texture.