Bob Vila's website rated interior paints as okay, better, and best. He rated flat as best and satin as better. Flat was especially recommended for ceilings. For trim work, satin was rated better and flat was unrated. http://www.bobvila.com/HowTo_Library/Selecting_the_Right_Paint_Sheen-Painting-A1951.html
Yes, depending on the mix ratio, you will end up with an eggshell or satin finish.
Yes or it can be the same as the wall paint if it should be flat.
Yes, you can generally paint high gloss latex over flat latex paint. But you must do all the preparation work in the best tradition of any professional painter. All "flaking" must be removed and the raw wood primed. This will present a "smooth" surface for the new coating. Additionally, everything that is to be painted my be scrupulously clean and free of anything that will restrict the new latex from sticking to the old.
Yes, you can mix satin and flat exterior latex paint, but it's important to note that the finish may not be consistent. Mixing different sheens can affect the final appearance, potentially resulting in a semi-gloss or uneven texture. It's advisable to test the mixture on a small area first to ensure you achieve the desired look. Always stir thoroughly to achieve a uniform blend.
If you want to turn your satin paint into flat wall paint simply mix one to one. One gallon of flat to each gallon of satin. The flat wall paint will obliterate any sheen the satin once had.
Yes. Sand the satin poly with fine sandpaper to remove the gloss, then coat with the flat poly.
You will have no problem painting satin over top of flat paint. Just remember to use the appropriate paint that will stick to the old coating. If the old coating is latex (water based) you can go over it with latex or alkyd (oil based) paint. If the old coating is oil based you can only go over it with oil based paint or a hi performance latex that is specialy made to go over oil. Most latex will not stick to oil based paint.
Yes, you can paint flat paint over satin paint as long as the surface is properly prepared and primed.
Put a good primer on it.
No, you can dull satin or semi-gloss but not the reverse.
it is cheaper when you go with three bedroom flat instead of going with three bedroom house. See related link.
If you have the satin, you can add flat paint and take some of the sheen off. This would have to be done before application. It will never be a true flat though.