Paint peels when it can’t stick to the surface underneath. The usual causes are moisture, poor preparation, incompatible paint layers and sun damage. To fix it, find the cause first, then scrape, clean, prime and repaint. Painting over peeling paint just makes the problem come back.
The main causes
Moisture. This is the most common culprit. Water can come from a leaking pipe, a roof or gutter problem, rising damp or a bathroom or laundry with poor ventilation. Damp walls push paint off from behind.
Poor preparation. Paint applied over dust, grease, mould or a glossy surface can’t grip. Cleaning and sanding are the steps that get skipped most.
Incompatible paints. Putting a water-based paint over an old oil-based coat without the right primer can cause it to peel. So can painting over a chalky surface.
Sun and heat. Strong UV breaks down paint over time, and paint applied in extreme heat can dry too fast and fail early.
Work out what’s going on
Touch the spot. If the wall feels damp or soft, moisture is involved. If the paint has peeled in sheets from a sun-exposed wall, weathering is more likely. If it’s peeling in a wet room, it’s probably humidity and ventilation. Find the cause before you do anything else.
Why it matters
Peeling paint is more than cosmetic. It exposes the surface underneath to water and weather, which leads to rot, rust and more expensive repairs. In older buildings, it can also release lead dust if lead-based paint is present.
A safety note on older buildings
If the building is older, the paint may contain lead, and older building materials may contain asbestos. Don’t dry-sand or scrape suspect surfaces. Have them tested and get advice from a qualified professional first.
How to fix it
- Fix the cause, such as a leak, ventilation problem or blocked gutter, and let the surface dry.
- Scrape and sand back all loose paint to a firm edge.
- Wash the surface to remove dust, grease and mould, then rinse and dry it.
- Fill and sand any repairs.
- Prime bare or patched areas with a suitable primer.
- Apply two coats of quality paint made for the room or the exterior.
Related problems
Our article on paint flaking and wrinkling covers similar failures, and our guide to water damage, mould and efflorescence explains how moisture ruins a paint job. To see how long a good finish should last, read how long exterior paint lasts.
Fix the cause, not just the paint
That’s what stops the peeling for good. See our residential painting and water damage repair services, or request a quote.
McAuliffe Painting. Eagle Farm, Brisbane QLD 4009. QBCC Lic 15183972.
