Overview

Painting interior walls means cleaning and prepping the surface, then applying primer (if needed) and one or two coats of wall paint with a brush and roller. It's one of the most common first DIY projects for homeowners and renters (with permission) because the tools are inexpensive, the skills are forgiving, and mistakes are easy to fix with a little sanding and a repeat coat. It's realistic for anyone comfortable spending a weekend on a ladder and willing to move furniture out of the way.

Tools & materials

  • Interior paint (in your chosen sheen) plus primer if needed
  • 2-2.5 inch angled sash brush for cutting in edges
  • Paint roller frame and 3/8 inch nap roller covers
  • Roller extension pole
  • Paint tray and disposable tray liners
  • Painter's tape
  • Canvas or heavy drop cloths
  • 120-grit sandpaper or a pole sander
  • Spackling compound or lightweight filler and a putty knife
  • Caulk and caulk gun for gaps at trim/ceiling lines
  • Tack cloth or damp rag for dust removal
  • Stepladder
  • Stir stick and paint can opener
  • Screwdriver for removing outlet covers and switch plates

Steps

  1. Clear the room of furniture or move everything to the center and cover it, and remove outlet covers, switch plates, and any wall hardware.
  2. Lay down drop cloths over the entire floor area you'll be working in.
  3. Fill nail holes and dents with spackling compound, let dry, then sand smooth; caulk any gaps between walls and trim or ceiling.
  4. Lightly sand the whole wall surface if it's glossy, patched, or previously painted with a different sheen, then wipe away dust with a tack cloth or damp rag.
  5. Apply painter's tape along trim, ceiling lines, and any adjacent surfaces you want to protect, pressing the edge down firmly with a putty knife.
  6. Apply primer over patches, stains, or when making a major color change; let it dry fully per the label before painting.
  7. Starting at the top of one wall, 'cut in' a 2-3 inch band along the ceiling line, corners, and trim using the angled brush.
  8. Load the roller evenly and work in overlapping W or M-shaped strokes across a 3x3 foot section, then fill in without lifting the roller, keeping a wet edge as you move to the next section.
  9. Work top to bottom on each wall, overlapping into the still-wet cut-in edges so you don't get lap marks.
  10. Let the first coat dry per the paint label (usually 2-4 hours), then apply a second coat the same way for even color and coverage.
  11. Remove painter's tape while the final coat is still slightly tacky (or once fully dry, per the tape instructions) by pulling it back on itself at a 45-degree angle.
  12. Reinstall outlet covers and hardware once the paint is fully dry, and let the paint cure for the time listed on the can before hanging anything or scrubbing the walls.

Safety warnings

  • Open windows and use fans to keep the room ventilated — paint and primer fumes (VOCs) can cause headaches or dizziness in an unventilated space
  • Wear a dust mask when sanding drywall patches or old paint to avoid breathing in dust
  • Use a properly rated, stable stepladder and don't overreach — keep your hips between the side rails
  • Wear safety glasses when working overhead or using a pole sander to keep dust and drips out of your eyes
  • If the home was built before 1978, assume old paint may contain lead and avoid dry-sanding it (a deeper lead-safety check is a separate topic)
  • Keep paint and solvents away from open flames or pilot lights, especially with oil-based products
  • Wash paint off skin promptly and keep lids closed on cans not in use to limit fume buildup

When to call a pro

  • You find soft, crumbling, or water-stained drywall, which points to an active leak that needs repair before painting
  • Walls have visible mold or a musty smell covering more than a couple square feet
  • You discover cracked plaster with movement (widening cracks) rather than simple hairline settling cracks
  • The home was built before 1978 and existing paint is peeling, chipping, or you plan to sand it extensively (get it tested for lead first)
  • Ceilings are higher than about 10-12 feet and require scaffolding rather than a standard ladder
  • You need to match or blend a complex faux finish, venetian plaster, or wallpaper removal before painting

Cost estimate

Roughly $150-$300 for an average 10x10-12x12 ft room, including paint, primer, and basic supplies (less if you already own brushes/rollers/ladder)

Sources