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When homeowners want a sleek, weather-resistant, and low-maintenance finish for their external walls, silicone render is often at the top of the list — and for good reason.
In this 2025 guide, we’ll walk you through:
- What silicone render is (and how it works)
- Why it’s so popular in UK homes
- What it costs in 2025
- How it compares to other render types like monocouche and cement
- When it’s the right (or wrong) choice for your property
Whether you’re refurbishing or building new, this guide will help you make the right decision — and avoid costly mistakes.
Table of Contents
What Is Silicone Render?
Silicone render is a modern thin-coat render used on external walls. It’s pre-coloured and mixed with silicone-based polymers that provide water repellence, flexibility, and long-term durability.
✅ It allows water vapour to escape (breathable)
✅ It resists rain and staining (hydrophobic)
✅ It doesn’t crack easily (flexible)
✅ It doesn’t need painting (colour-fast)
This makes it ideal for:
- British weather (rain, frost, UV, algae)
- Renovations of older homes
- New builds and extensions
- Properties with insulation systems (EWI)
What Is Johnstone’s Stormshield Silicone Render?
At P3 Plastering, we primarily use Johnstone’s Stormshield Thin Coat Silicone Render, one of the most trusted systems on the UK market.
It comes in:
- Over 150 colours
- Multiple grain sizes (1mm, 1.5mm, 2mm)
- Options for spray or hand-application
It’s through-coloured (so the colour runs through the material), meaning it won’t peel or fade like paint.
Silicone Render Application Process (How It’s Installed)
How long does silicone render last?
25–30 years with basic maintenance.
Do you need to paint it?
No — it’s pre-coloured and fade-resistant.
Can you apply it to old houses?
Yes, but proper basecoat and mesh is essential. We regularly retrofit silicone render to Victorian and 1930s properties.
How do you maintain it?
Hose it down every year. Algae can be treated with softwash.
Does it come in different textures?
Yes — most popular is 1.5mm grain, but 1mm and 2mm are also available.
Here’s how a professional team (like ours) applies silicone render for a smooth, lasting finish:
1. Surface Prep
We clean and patch the wall to ensure a sound, even surface.
2. Basecoat & Mesh
A specialist adhesive basecoat is applied with fibreglass mesh embedded. This adds strength and prevents cracking.
3. Primer
A coloured or clear primer is applied to regulate suction and help adhesion.
4. Silicone Topcoat
The final layer is applied using a float or spray — usually 1.5mm thick.
The process takes 3–6 days depending on property size, drying time, and weather.
Key Benefits of Silicone Render
✅ Water-Repellent
Water beads and rolls off — reducing algae, lime bloom, and discolouration.
✅ Breathable
Allows moisture vapour to escape, preventing damp inside walls.
✅ Flexible
Handles expansion, contraction, and settlement without cracking.
✅ Pre-Coloured
No painting required — and it won’t peel or flake like masonry paint.
✅ Algae-Resistant
Ideal for damp, shaded, or exposed areas (like North-facing walls).
✅ Easy to Maintain
Just hose down every now and then — no harsh pressure washers needed.
Silicone Render vs Monocouche vs Cement: 2025 Comparison
Feature | Silicone Render | Monocouche Render | Cement Render |
Breathable | ✅ Yes | ⚠️ Moderate | ❌ No |
Water-Repellent | ✅ Excellent | ⚠️ Average | ❌ No |
Crack Resistance | ✅ Excellent | ⚠️ Moderate | ❌ Poor |
Maintenance | ✅ Very low | ⚠️ Mid-level | ❌ High |
Lifespan | ✅ 25–30 years | ⚠️ 15–20 years | ❌ 10–15 years |
Colour Choice | ✅ 100+ colours | ✅ 50+ colours | ❌ Needs painting |
Cost | ⚠️ Highest | ✅ Mid-range | ✅ Lowest |
If you’re looking for long-term value and want to avoid constant upkeep, silicone render is the best-performing system — especially in the UK climate.
While silicone render is known for its breathability and flexibility, acrylic render is another excellent option for homeowners seeking vibrant colour and long-lasting finishes on exterior walls. Learn more about silicone render vs monocouche in our comparison post here.
Silicone Render Cost Guide – 2025 UK Averages
Pricing can vary significantly based on:
- Size of the area
- Wall condition
- Whether scaffolding is needed
- Colour/grain preferences
Average Prices:
Property Type | Estimated Cost (Render Only) |
Small extension or garage | £800–£1,200 |
Semi-detached house (2-bed) | £4,000–£6,500 |
Detached house (4-bed) | £6,500–£11,000 |
Scaffolding (if needed) | £600–£1,200 extra |
💬 We always offer free on-site surveys to give accurate, transparent quotes based on your property and needs.
When Is Silicone Render the Right Choice?
✅ You want a clean, modern look with no need to repaint
✅ You live in a damp or exposed area (like shaded or coastal walls)
✅ You’re rendering over EWI or new blockwork
✅ You want low maintenance and long life
When It’s Not the Best Fit:
❌ You’re on a very tight budget
❌ You’re rendering a boundary wall with frequent impact/damage
❌ You want a very textured or traditional finish (lime or dash)
In these cases, monocouche or even lime render might be better.
FAQs About Silicone Render
Close-Up: 1.5mm Silicone Render Finish
This detailed image shows the fine 1.5mm grain texture of Johnstone’s Stormshield Silicone Thin Coat Render.
The smooth, consistent finish offers a clean, modern appearance that’s both low-maintenance and highly weather-resistant. The 1mm grain is our favourite finish and is also the most popular request due to its subtle texture and professional look.
See Our Service Page for Details
Want to see colour charts, technical specs, and real examples of our work?
📍 Visit our Silicone Render Services Page for more in-depth info and to request a quote.
Final Thoughts
In 2025, more homeowners are choosing silicone render for its resilience, appearance, and value. While it may cost more upfront than cement or monocouche, it pays off with fewer issues, better looks, and long-lasting performance.
At P3 Plastering, we’ve applied Johnstone’s Stormshield Silicone Render to homes across South Yorkshire, helping our clients transform tired exteriors into vibrant, weatherproof façades that last.
📞 Ready to transform your home?
Need tailored render advice for your property? Request a free rendering quote today and speak with one of our experts.
