Why Is My Exterior Paint Fading or Bleaching in Patches?

Have your exterior walls lost their colour? Maybe they're looking chalky, patchy, or even bleached in spots?

You’re not imagining it — and you’re not alone.

“Why is my outside paint fading so fast?”

This is one of the most searched homeowner problems in South Africa. And it’s one we know how to solve.

Let’s break down the science behind washed-out paint — and how to prevent it.

1. The Sun Is Fading Your Paint

South Africa’s intense sunlight is beautiful — but brutal on paint.

UV (ultraviolet) rays attack the pigments and break down the paint’s binder over time. The result? Fading, patchy areas, and that “bleached” look.

Areas in full sun fade faster than shaded ones — especially if the paint lacks UV stabilisers or pure acrylic resins.

2. Moisture Causes Chalking and Patchiness

If water seeps behind the paint film — from leaky gutters, unsealed plaster, or damp rising up from the ground — it weakens the coating. The binder can break down, leaving behind a powdery chalk residue. This makes paint appear dull, uneven, and almost dusty to the touch.

You will usually see this around the base of walls, window sills, or spots where rain hits directly.

3. Alkali Burn: The Hidden Enemy

Fresh plaster and cement are highly alkaline. If you paint directly onto them without sealing properly, that alkaline residue (salts) can chemically react with the paint — causing it to fade or bleach rapidly.

This is where ARP (Alkali Resistant Primer) is essential.

ARP primers create a barrier between the alkaline substrate and your topcoat, locking in salts and stopping colour fade, blistering, or peeling before it even starts.

If you skip this step, even the best paint can’t save you.

4. Cheap Paint = Short-Term Results

Here’s the tough truth: cheap paint fades faster.

Budget paints often use low-grade binders, weak pigments, and little to no UV protection. These break down quickly under South African weather conditions — especially if applied without a quality primer.

You may think you're saving money — but when you repaint in a year, the real cost shows up.

5. The Prep Matters Just As Much As the Paint

No exterior paint will last if the surface beneath it is unstable.

Common problems:

- Unwashed walls with dust or efflorescence (salt)

- Painting directly onto raw plaster or cement without primer

- Skipping the ARP primer step altogether

For a long-lasting finish, start with a thorough clean, followed by a masonry primer, and always use an alkali-resistant primer on any cementitious or newly plastered wall.

How to Fix It — and Prevent It Happening Again

- Use ARP Primer on all raw plaster and cement before painting

- Choose a pure acrylic, UV-stable exterior paint like Harlequins Satin Sheen or Washable Matt.

- Avoid painting during hot sun or heavy moisture

- Don’t skimp on prep — clean, prime, seal, and then paint

Final Word: Fading Paint Isn’t Just Sun Damage

It’s often a sign that something was skipped — the wrong product, poor preparation, or no ARP primer.

At Harlequin, we don’t just sell paint — we solve paint problems.

Need advice? Bring us a photo, a peeling paint sample, or just pop in for a chat.

We'll help you paint it once — and paint it right.