There is a new category of paints that claim to be a primer/paint combination. They are touted to have excellent hiding and durability. These paints are useful in certain conditions, but recently have become advertised as an all around paint. The paint/primer material makes for a thick paint that doesn’t perform as good as a primer or even as a stand alone paint. They should never be used to replace a good subsurface primer or trim paint. Because of its thickness, it has very little leveling ability. So make sure you always feather out brush and roller marks, or they will become part of the texture. Also, due to its thickness, it takes longer to paint a room compared to using a conventional acrylic paint. Also a conventional paint will hold its color longer than a paint/primer.
When is paint/primer combo a good choice? They make a good choice when you want to color change a wall, and need to cover a strong color. A paint/primer might just fully cover in two coats instead of three with a conventional paint. Otherwise, given the choice, always choose a primer for a primer project; A paint to paint a wall.
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