Paint peels when it loses adhesion to the surface beneath it, often because of moisture, poor preparation, incompatible coatings, or substrate movement. Before sanding and repainting, confirm the wall is dry and sound; otherwise the repair is likely to fail again.
Check for moisture before blaming the paint
Staining, soft edges, peeling near windows or pipes, and worsening after rain point toward moisture. Correct the leak, condensation, or intrusion and let the material dry before repairing the finish.
Dirty or glossy surfaces can also lose adhesion
Grease, dust, chalky plaster, and glossy paint that was not prepared can keep a new coat from bonding. If the wall is dry, review the surface preparation and whether the coating was compatible.
Widespread peeling in an older home raises lead-paint concerns
Older homes can have historic lead-based layers beneath newer paint. Before sanding or scraping large areas, especially where lead paint is plausible, use appropriate testing and lead-safe work practices.
Repair only holds after the cause is fixed
Remove only loose material, stabilize the substrate, prime where appropriate, and repaint with a compatible system. If the wall remains damp, soft, or extensively moldy, fixing the source and damaged material comes first.
Sources
- U.S. Environmental Protection Agency (EPA) — Mold and Moisture — Moisture control, mold prevention, cleanup, and recurrence.