Overview
Discolouration comes in green (algae), black (mould), white (salt) or dull (UV). Each has a different treatment.
Symptoms
- Green stains - north-facing damp.
- Black spots - mould.
- White haze - salt.
- Overall dulling - UV.
Common causes
- Coastal exposure.
- North-facing damp.
- UV.
When to call a professional
- Any suspected coating failure.
Prevention
- Wash every 3 months.
- Annual wax.