Promising faster application and lower costs, one coat render tempts many UK homeowners and builders. But does this shortcut compromise your home’s weather resistance and longevity? This guide cuts through the hype – explaining where it might work, its serious limitations, and why systems like silicone render or acrylic rendering deliver better value long-term.
One coat render is a pre-mixed cementitious product applied in a single 10-15mm layer (vs. traditional 2-3 coats). Key features:
⚠️ Limited niche use only:
❌ Poor Crack Resistance:
Single layers lack the flexibility of modern acrylic rendering or silicone render. Prone to cracks in render from thermal movement or substrate shrinkage.
❌ Trapped Moisture & Damp:
No dedicated scratch coat render base means:
❌ Short Lifespan:
Lasts 5-8 years in UK climates vs. 20-25+ years for quality 2-coat systems.
❌ Finish Limitations:
Cannot replicate textured finishes like pebble dash or Tyrolean render. Smooth only.
❌ False Economy:
Lower upfront cost erased by frequent repairs:
*"Saving £15/m² on installation often costs £60/m² in repairs within a decade."*
– Richard Renderman, MidRender
| Factor | One Coat Render | Modern 2-Coat Systems (e.g., Silicone Render) |
|---|---|---|
| Application Time | 1 day | 2-4 days |
| Crack Resistance | Low | High (flexible polymers) |
| Breathability | Poor | Excellent (reduces damp risk) |
| Durability | 5-8 years | 20-25+ years |
| Finish Options | Smooth only | Smooth, textured, pebble dash, Tyrolean |
| Long-Term Cost | Higher (repairs) | Lower (minimal maintenance) |
For durable, low-maintenance results, invest in:
No. External Wall Insulation requires specialised flexible systems. One coat will crack and detach.
Yes. Requires masonry paint within 4 weeks for minimal weather resistance. Expect repainting every 3-5 years.
Speed and lower labour costs appeal to contractors on tight schedules. Not in the homeowner’s long-term interest.
Rarely successful. Poor adhesion and differential curing cause delamination. Full removal is usually needed.
One coat is cheapest upfront (£15-£25/m² installed). For true value, acrylic rendering is smarter – lasts 3x longer with 80% less maintenance.
