What do goache and watercolour have in common? Can you layer watercolour over gouache?

Answer 1

Or, in simpler terms, Gouache is opaque and watercolour is transparent. They are both water-soluble, using gum arabic as a binder, but gouache has titanium oxide added to make it opaque.

You can begin with transparent watercolour and layer over top with gouache, but the two paints look entirely and obviously different. You can water down gouache to make it almost transparent, but it refracts light differently than watercolour and should not be used in conjunction with the other unless you want the difference to be obvious..

Answer 2

No! You are talking about two different techniques. They are similar in being water based, but different in the texture of the medium. You can lay a wash of diluted colour on a ground and then overbrush with gouache.You could experiment with a wash over gouache but because the watercolour is transparent nothing much would happen. A gouache work uses the texture of gouache and the diluted colours that result form creating washes from the body colours.

Answer 3

They are bot water based. you can mix quash with aquarell...using white guash and the color of the watercolor. I think also that it should be ok to go over guash with watercolor.
The best is to try it out.
As much as I know , it is "dangerous" to go with waterbased techniques, over oily techniques, because it will make the paint crack or opeel of. Vice versa should be ok ..and I use a lot of mixed media. I love mixing watercolour, guash and aquarel color pencils.
good luck with your work.