# Wrinkling

Source: https://coatmentor.com/defects/wrinkling/ · Updated 2026-10-14

A rough, shrivelled surface of ridges and valleys, like the skin of a prune, often on flat surfaces where a heavy coat was laid.

*Figure: Wrinkling: the surface as you see it, and a schematic cross-section.*

## Causes

- Film too thick: the surface skins over while the paint below is still soft.
- Oxidative coatings such as alkyds, which cure from the surface down.
- Heat or sun on the fresh film, or recoating a coat that is not dry enough.
- Rain, dew or high humidity on uncured paint.

## Prevention

- Apply even coats at the specified wet film thickness.
- Keep to the drying times and temperatures of the product data sheet.

## How it is assessed

Visual. Check the wet and dry film thickness records and the conditions during cure.

## Repair

Remove the wrinkled coat to a sound surface, sand or abrade it smooth, and recoat at the right thickness. The specification and the coating manufacturer have the final word on the repair procedure.

**15** practice items in the members area mention wrinkling (CIP 1: 2 · CIP 2: 11 · FROSIO written: 2).

## Related

- **Concepts:** [Drying, curing and recoat windows](https://coatmentor.com/learn/cure-and-recoat/) · [Volume solids, wet film and dry film](https://coatmentor.com/learn/volume-solids/)
- **Standards:** [SSPC-PA 1](https://coatmentor.com/standards/sspc-pa-1/)

## About this page

Written from coating practice and the published rating standards, in our own words; the drawing is schematic. Checked on 2026-10-14; errors go in the [corrections log](https://coatmentor.com/method/). CoatMentor is an independent study aid. It is not affiliated with ISO, AMPP, SSPC, NACE International, ASTM or FROSIO.