How do I prepare walls for painting?

Proper wall preparation is the most critical step for achieving a professional-looking paint job that will last for years. The time you invest in prep work directly determines how smooth, even, and durable your final finish will be.

Start by thoroughly cleaning your walls with a mild detergent solution to remove dirt, grease, and any residue. Pay special attention to areas around light switches, door frames, and kitchen walls where buildup is common. Allow walls to dry completely before proceeding. Next, inspect for holes, cracks, and imperfections that need repair. Small nail holes can be filled with lightweight spackling compound, while larger holes may require mesh patches or even small drywall repairs.

Sanding is essential for both smoothing repairs and creating proper adhesion. Use 120-grit sandpaper for most surfaces, focusing on any patched areas, glossy spots, or rough textures. After sanding, wipe down walls with a tack cloth to remove all dust - this step is crucial as paint won't adhere properly to dusty surfaces. For previously painted walls, you'll need to determine if the existing paint is oil-based or latex, as this affects your primer choice.

Priming is non-negotiable for most painting projects, especially in Ottawa's climate where temperature and humidity fluctuations can affect paint adhesion. Use a high-quality primer appropriate for your surface - latex primer for most interior walls, or a specialized primer for challenging surfaces like glossy paint, stains, or new drywall. Prime all repaired areas, and consider priming the entire wall if you're making a significant color change or painting over a darker color.

Professional preparation techniques include removing outlet covers and switch plates, protecting floors and furniture with drop cloths, and using painter's tape on trim and ceilings. Apply tape carefully and remove it while the final coat is still slightly wet to prevent peeling. For textured walls common in many Ottawa homes, you may need to use a thicker nap roller or brush to ensure even coverage in all the crevices.

When to call a professional: If you discover extensive wall damage, lead paint (common in Ottawa homes built before 1978), or if you're dealing with plaster walls that need significant repair, consider hiring a professional painter. The investment in proper preparation will save you money long-term by ensuring your paint job lasts 7-10 years instead of needing touch-ups in 2-3 years.

Next steps: Purchase quality primer and paint, gather all necessary tools, and plan for 2-3 days total (prep day, prime day, paint day) to avoid rushing the process and compromising results.