Render does more than make a house look smart — it’s the first line of defence against the weather. When it starts to fail, water gets behind it and the problem only spreads. Here are five signs it’s time to act.
1. Cracks in the surface
Fine hairline cracks are common and often cosmetic, but wide, deep or spreading cracks let water in. Once moisture sits behind the render through a freeze-thaw winter, small cracks quickly become big ones.
2. Hollow or “blown” patches
Tap the wall. If sections sound hollow and drum-like, the render has lost its bond with the wall behind — that’s “blown” render. It can’t be painted over; it needs cutting out and re-rendering.
3. Bulging or crumbling areas
Render that’s bulging, flaking or coming away in pieces has failed and is letting water track behind the rest of the surface. Left alone, sound areas nearby will start to go too.
4. Damp patches and staining inside
Failing render outside often shows up as damp patches, tide marks or staining on internal walls. If you’re seeing damp inside, the exterior is a common culprit worth checking.
5. Green growth and constant moisture
Persistent algae, moss or green staining suggests the surface is holding water rather than shedding it — a sign the render (or the paint over it) is no longer doing its job.
Repair or replace?
Not every problem means a full re-render. Isolated damage can often be patch-repaired and blended; widespread failure is better fixed with fresh render across the elevation. The key is dealing with it before water does more damage.
We’ll assess it honestly and quote a fixed price for whichever your walls actually need. Based in Harefield, covering Middlesex and the Home Counties.
Get a free quote or call 07734 903439.