is Valspar ok to use on new plaster

When applying paint to fresh plaster work you should apply 2 'Mist Coats' of paint. Get a bucket, add roughly 2.5L of paint and roughly 2.5L of water. (These are examples, the mist coat goes a long way so don't mix up too much or you will waste it). Give it a good mix and it will turn into a milk like substance. Apply one coat to the new plasterwork and allow to dry. Don't worry about any tram lines from the roller or anything really at this stage. Once dry apply another coat. you will begin to notice that you are getting some coverage now. Whilst the mist coat is wet take a second to look over the plaster work for imperfections and do some filling at this stage. If you are using valspa I would then apply a normal coat of paint. Again check for imperfections, minor fills. Rub back the filler and apply another coat. Then have a look at the walls. Id suspect with Valspa, you would need 2 mist coats and 3 normal coats as it doesn't have great coverage. the whole idea of a mist coat is to bridge the gap between the plaster and the paint. If you put normal Vinyl matt onto the plaster work the paint will effectively sit on top of the plaster and eventually peel off. I would recommend using a medium length pile roller head. Ask your decorators merchant for one. Follow those instructions and you aught to have not far from a professional decorators finish. Hope this has helped, good luck with your project.

Best to thin with water for a mist coat.

Shouldn't need 2 mist coats and 2 coats of paint. Any other paint you need 1 mist coat and 2 coats of pain. Not 4 coats. Joke.