Render Cracking vs Render Failure: What’s the Difference?
Not every crack in your render means something has gone seriously wrong, but it can be hard to tell the difference between a cosmetic issue and a sign of genuine render failure. Here’s how to tell them apart, and what to do about each.
What Counts as Normal Cracking?
Fine, hairline cracks that follow no particular pattern are extremely common, especially in traditional sand and cement render, and are usually caused by natural shrinkage as the render cures or by minor building movement. These cracks rarely let in significant amounts of water and can often be monitored or filled as part of routine maintenance.
Signs of Genuine Render Failure
Render failure is a different matter. Watch for cracking that follows a clear pattern (such as along a straight line or around a window), sections that sound hollow or drum-like when tapped, visible bulging or lifting away from the wall, and damp patches appearing on internal walls. These are signs that water has got behind the render and the bond to the substrate has broken down, meaning the affected area needs proper repair rather than a simple patch.
Our rendering repair guide goes into more detail on diagnosing these problems, and if you’re unsure which type of render is best suited to preventing failure in future, our comparison of K-Rend and traditional render is a good place to start.
What to Do Next
If you’re not sure whether what you’re seeing is cosmetic cracking or a sign of failure, it’s always worth getting a professional opinion before the problem gets worse or more expensive to fix. SM Rendering offers free, no-obligation inspections across Staffordshire and Cheshire, including Stafford and Uttoxeter. Contact us to arrange a visit.
