Why Is My Render Cracking? Common Causes & How to Fix It

Your render should protect and enhance your home – not leave it looking cracked, stained or damaged. 

If you’ve noticed cracks, discolouration or patchy render, you’re not alone. These can be early warning signs of more serious issues, but with the right care, most render problems can be cleaned, maintained – or prevented altogether

Top Reasons Why Render Cracks 

1. Water Ingress 

Moisture is one of the most common causes of render damage. Water can seep into small cracks or behind the render layer, weakening what’s underneath. When temperatures drop, the trapped moisture freezes and expands – causing larger cracks or even causing the render to blow (detach from the wall). 

2. Temperature Fluctuations & Shrinkage 

Render expands and contracts with changes in temperature. Over time, this natural movement can create hairline cracks – especially if the render wasn’t applied or cured properly. 

3. Poor Application or Substrate 

If the render was applied too thickly or onto a surface that wasn’t properly prepared, cracks are more likely to develop. Other issues include: 

  • Weak or crumbling substrate 
  • Poor weather conditions during application 
  • Lack of expansion joints in large areas 

How to Fix or Prevent Render Cracks 

✅ Clean It: Soft Washing for Render 

Organic growth – like algae, moss and red staining – traps moisture and accelerates render deterioration. Our gentle soft washing method removes it safely, using HSE-approved solutions to kill spores at the root. 

  • No high pressure 
  • No damage to your render 
  • Just a clean, bright, protected surface 

✅ Maintain It: Regular Biocide Treatments 

After cleaning, a biocide treatment keeps your render protected long-term. These prevent re-growth, maintain appearance, and prolong the lifespan of your render. 

✅ Prevent It: Act Before Damage Starts 

Noticed a lot of dirty or cracked render in your neighbourhood? That means spores are in the air and could be spreading. A proactive spray treatment prevents those spores from settling on your home – and helps you avoid costly repairs down the line.

Why It’s Important 

Cracks and stains on render aren’t just cosmetic. Left untreated, they can: 

  • Allow water into your walls 
  • Compromise insulation 
  • Lead to damp or structural issues 
  • Reduce your property’s value 

Render Cleaning & Maintenance with My Property Pros 

At My Property Pros, we offer safe, specialist render cleaning across the UK – helping homeowners protect and preserve their properties. 

  • ✔️ Suitable for all render types 
  • ✔️ Pet and family safe solutions 
  • ✔️ No pressure – no damage 

Book your free quote today and give your render the care it deserves. 

Want a Hassle-Free Solution? Sit Back and Relax – Our Experts Have You Covered.

My Property Pros
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