Grease on painted walls needs a cleaner that emulsifies oil without polishing or lifting the finish. Start with warm water and a small amount of mild detergent, work without aggressive scrubbing, and dry afterward. Flat and older paints are more prone to burnishing than washable semi-gloss finishes.
Test an inconspicuous area first
Dampen a white cloth and check whether it picks up color or changes sheen. If the paint softens or transfers, stop the wet method and check manufacturer guidance or consider repainting.
Use a small amount of soapy solution in sections
Use only the necessary concentration of mild detergent and apply it with a cloth rather than soaking the wall. Work carefully in manageable sections and follow with a clean cloth to remove residue.
Avoid abrasives that create a shiny patch
Very abrasive pads or melamine erasers can change the texture of flat paint even when they remove grease. If more cleaning action is needed, increase dwell time or repeat gently before increasing abrasion.
A stain bleeding through paint may need primer
Old grease, smoke, or contamination in the substrate can reappear after cleaning. When the wall is clean and dry but the stain still bleeds through, a compatible stain-blocking primer and repainting may be more effective than continued scrubbing.
Sources
- American Cleaning Institute — Cleaning Tips — General cleaning practices and product use according to labels and surfaces.