Paint-and-Primer in One Works — Except on Raw Surfaces

The Problem

Paint-and-primer "all-in-one" products promise to save you a coat, and plenty of DIYers read that as "primer is obsolete." Then they roll all-in-one straight onto bare drywall or raw wood and wonder why the finish shows every roller mark and takes three coats anyway.

The Technique

The decision comes down to what's under the paint:

• Previously painted surface — use the all-in-one straight away. Skipping the primer step is exactly what it's made for, and on a sound painted surface it performs as promised.
• Raw surface (bare drywall that's never been painted, bare wood) — put down a dedicated primer first. Primer is thinner than all-in-one paint, so it absorbs into the raw material, flattens out with less stipple and fewer brush marks, and leaves a smoother foundation for the topcoat.

There's a cost argument on top of the finish argument: dedicated primer runs about half the price of all-in-one paint. If a raw surface ends up needing three coats — and it often does — you'd rather one of them be the inexpensive coat that's purpose-built for the job.