Interior Paint: Surface Prep, Sheen Types, and the Steps Professionals Don't Skip

Wash walls with a mild detergent solution — a bucket of warm water with a small amount of dish soap works for most rooms. Pay attention to areas around light switches, near the stove, and along baseboards where grease, dust, and oils accumulate. These residues prevent paint from bonding. Rinse thoroughly and let walls dry completely before moving on.

While the walls dry, look for cracks, holes, water stains, or peeling areas. Mark each one with a piece of tape so nothing gets missed.

Apply patching compound to nail holes, hairline cracks, and any divots using a putty knife. Overfill slightly, let it dry fully (check the label — most need at least two hours), then sand flush with the surrounding surface using a sanding sponge. For larger cracks or damaged sections of drywall, a second thin coat of compound after sanding is often needed.

Once patches are smooth, lightly sand any areas where old paint is chipped or where the surface transitions between materials. Feathering the edges prevents visible ridges under the new coat.

Primer isn't always required — but when it is, skipping it almost always shows up as uneven coverage, bleed-through, or poor durability. Prime in these situations: new or unpainted drywall, patched areas larger than a coin, surfaces with water stains or smoke damage, and any time you're making a drastic color shift (especially going from dark to light).

Tinted primer (ask the paint counter to tint it close to your topcoat color) reduces the number of finish coats needed for full coverage. Let primer dry completely before painting over it.

Apply painter's tape along trim, baseboards, window casings, and the ceiling line wherever you need a clean edge. Press the tape edge firmly with a putty knife or your fingernail to prevent paint from bleeding underneath. Lay drop cloths across the floor and over any furniture remaining in the room.

Remove outlet cover plates and light switch covers entirely — painting around them wastes time and looks less professional than reinstalling clean covers after painting.

Using your angled brush, paint a 2–3 inch band along all edges — corners, ceiling lines, trim, and around outlets. This is called cutting in, and it creates a finished border that the roller can't reach cleanly. Work in manageable sections (one wall at a time) so the cut-in edge is still wet when you roll adjacent to it. Painting into a dry edge creates visible lines called lap marks.

Load the roller evenly — avoid overloading, which causes drips — and apply paint in a loose W or M shape across a roughly 3×3 foot section. Then fill in the pattern with smooth vertical strokes without lifting the roller. This distributes paint evenly without streaks. Overlap each section slightly while it's still wet to blend edges seamlessly.

Maintain a wet edge throughout. If you stop mid-wall and let paint dry before finishing, the overlap will be visible in certain lighting.

Check the paint can's recoat time — typically two to four hours for latex paints, but humidity and temperature can extend this. Applying a second coat too soon traps moisture and leads to peeling. Once the first coat is dry, repeat the cut-in and roll sequence. Two thin coats provide better coverage, more even color, and better durability than one heavy application.