Advice & Technical Support.

Why Do My Walls Keep Getting Wet After Rain? (Causes & Solutions)
 

By Miya Paint & Waterproofing Experts – www.miyaconnection.co.za

 

 

When rain arrives, many homeowners expect their homes to stay dry and secure. But for thousands of South Africans, wet walls after rain have become a recurring headache—leading to mould, peeling paint, musty smells, and long-term structural damage.

 

If your walls keep getting wet after every rainfall, you're not alone—and the problem is almost always preventable.

 

Let’s break down the real reasons this happens and what you can do.

 

⭐ Top Reasons Your Walls Get Wet After Rain
 

1. Penetrating Damp (Rainwater Seeping Through the Wall)

 

This is the most common cause.

 

Rain beats against the exterior wall → moisture breaks through the plaster → the interior walls get wet.

 

Causes

 

  • Cracked exterior walls
  • Old, worn or poor-quality paint
  • Weak plaster
  • No waterproof barrier or failed waterproofing
  • South-facing walls exposed to continuous rain

 

Solution

 

  • Repair cracks & plaster weaknesses
  • Apply a high-quality waterproof barrier
  • Repaint using a UV- and rain-resistant coating

 

 

At Miya Paint & Waterproofing, we use SABS-approved materials with a 5–10 year lifespan guarantee.

 

 

2. Rising Damp (Moisture Moving Up from the Ground)

 

For houses without a proper damp-proof course (DPC), groundwater rises through the walls.
Rainfall increases moisture in the soil → the damp climbs even higher → your walls stay wet longer.

 

Signs

  • Paint bubbling at the bottom
  • White “salt powder” crystals
  • Wetness up to 1m high

 

Solution

  • Damp-proof injection systems
  • Membrane installation
  • Replastering with salt-resistant waterproof plaster

 

3. Leaking Gutters & Downpipes

 

If gutters overflow or spill water onto your walls, it saturates the surface and seeps inside.

 

Solution

  • Clean gutters
  • Repair leaks
  • Realign gutters to correct slope

 

4. Roof Leaks Causing Wall Damp

 

Sometimes the wall isn’t the problem—the roof is.
Water finds a gap → travels along rafters → ends up on your wall.

 

Solution

  • Patch or replace roofing sheets
  • Seal flashings
  • Re-waterproof valleys and roof joints

 

5. Poor Ventilation & Internal Condensation

 

Cold walls + humid indoor air = moisture forming on the surface.

 

Solution

  • Improve airflow
  • Install extractor fans
  • Use anti-condensation paints

 

 

📊 South African Statistics You Should Know

 

 

✓ 67% of home damp problems come from failed waterproofing

 

✓ 1 in 3 homes over 10 years old experience penetrating damp

 

✓ Damp problems decrease property value by 10–15%

 

 
🛠️ Professional Fixing vs DIY

 

DIY can help temporarily—but without proper waterproofing materials, the damp will return, often worse than before.

 

 

Miya Paint & Waterproofing offers:

 

✔ Damp proofing

 

✔ Waterproofing

 

✔ Roof leak repairs

 

✔ Wall sealing

 

✔ Interior/exterior painting

 

✔ Ceilings & renovations

 

 

🔧 Final Word: Wet Walls After Rain Are Fixable

 

Wet walls are a serious warning sign.

The longer you wait, the more expensive the repair becomes.

 

Let the experts handle it.

 

Click to Get Professional Help:

👉 www.miyaconnection.co.za
👉 WhatsApp: 066 036 1296