Silicone and acrylic render systems

Silicone and acrylic render systems are two of the most widely used finishing solutions for External Wall Insulation (EWI) projects in the UK. They provide a protective, decorative, and long‑lasting outer layer that not only shields insulation boards from the elements but also enhances the appearance of any property. As homeowners, contractors, and architects look for ways to improve energy efficiency, reduce maintenance, and achieve modern aesthetics, silicone and acrylic renders have become the preferred choice.

Unlike traditional cement renders, which are prone to cracking and fading, silicone and acrylic finishes are polymer‑based, flexible, and engineered to withstand the UK’s challenging climate. They are available in a wide range of colours and textures, making them suitable for both residential and commercial projects.

What Are Silicone and Acrylic Renders?

Acrylic render is a polymer‑modified finish coat that has been used successfully for decades in external wall insulation systems. It is known for its strong adhesion, vibrant colour options, and cost‑effective performance. Acrylic render is particularly valued in projects where affordability and design flexibility are priorities.

Silicone render represents the next generation of façade technology. It is breathable, highly water‑repellent, and self‑cleaning. Silicone render is designed to cope with heavy rainfall, frost, and pollution, making it ideal for the UK climate. It is also UV‑stable, meaning colours remain vibrant for many years without fading.

Both systems are applied as the final stage of an EWI installation. After insulation boards and reinforcing mesh are fixed and covered with a base coat, the render is applied in a thin layer, usually between 1.5 and 3 millimetres. This creates a durable, attractive, and weather‑resistant finish.

Benefits of Silicone Render

Silicone render is chosen for projects where long‑term durability and minimal maintenance are priorities. Its main advantages include:

• Water resistance: silicone render repels rainwater, preventing moisture penetration.

• Self‑cleaning properties: dirt and pollutants are naturally washed away by rainfall, keeping façades clean.

• High breathability: moisture inside the wall can escape, reducing the risk of damp.

• UV stability: colours remain bright and consistent even under prolonged sun exposure.

• Long lifespan: with proper installation, silicone render can last 25 to 30 years.

• Low maintenance: requires little more than occasional rinsing with water.

Benefits of Acrylic Render

Acrylic render remains a popular choice for projects where cost and colour flexibility are important. Its advantages include:

• Strong adhesion: bonds securely to insulation boards and base coats.

• Wide colour range: available in hundreds of shades, making it easy to match design requirements.

• Cost‑effective: more affordable than silicone render, making it suitable for budget‑sensitive projects.

• Durability: resistant to cracking and impact damage.

• Proven track record: acrylic render has been used successfully in EWI systems for decades.

Silicone or Acrylic – Which to Choose?

The choice between silicone and acrylic render depends on project priorities. Silicone render is ideal for clients who want maximum durability, water resistance, and minimal maintenance. It is particularly suited to properties in harsh climates, polluted urban areas, or coastal regions where salt and moisture are constant challenges. Acrylic render, on the other hand, is a strong option for projects where budget is limited but a durable and attractive finish is still required. It is also the better choice when a very specific or vibrant colour is needed.

Applications in the UK

Silicone and acrylic render systems are widely used across the UK in a variety of projects:

• Residential retrofits: upgrading older solid wall homes with EWI and a modern finish.

• New builds: providing sleek, contemporary façades for houses and apartments.

• Commercial properties: offices, schools, and retail units requiring durable, low‑maintenance exteriors.

• Urban environments: silicone render is especially popular in polluted cities due to its self‑cleaning properties.

• Coastal areas: silicone render is highly resistant to salt and moisture, making it ideal for seaside properties.

Installation Process

The installation of silicone and acrylic render systems follows a multi‑layered process:

1. Preparation of the wall surface and secure fixing of insulation boards.

2. Application of a reinforced base coat with embedded mesh for strength.

3. Application of a primer to improve adhesion and colour consistency.

4. Application of the top coat render, either silicone or acrylic, in the chosen texture and colour.

This process ensures that the building is both energy‑efficient and protected from the elements.

Energy Efficiency and Compliance

When combined with external wall insulation, silicone and acrylic renders contribute significantly to energy savings. They reduce heat loss, lower heating bills, and improve comfort inside the property. They also help buildings comply with UK building regulations, particularly Part L, which focuses on energy efficiency. Improved EPC ratings increase property value and marketability, while supporting the UK’s Net Zero carbon reduction goals.

Maintenance and Longevity

Silicone render requires very little maintenance. Its self‑cleaning properties mean that façades remain fresh for many years with minimal effort. Acrylic render may require more frequent cleaning, especially in polluted areas, but it remains durable and resistant to cracking. Both systems are flexible and less prone to damage than traditional cement renders.

Frequently Asked Questions

How long do silicone and acrylic renders last?
Silicone render can last 25 to 30 years, while acrylic render typically lasts 20 to 25 years.

Are these systems suitable for older houses?
Yes. Both silicone and acrylic renders are widely used in retrofit projects for solid wall properties.

Do they require repainting?
No. The colour is embedded in the render, so repainting is rarely necessary.

Which is better for the UK climate?
Silicone render is often preferred for its water resistance and self‑cleaning properties, but acrylic remains a strong, cost‑effective option.

Can I choose any colour?
Yes. Both systems are available in a wide range of colours, with silicone offering superior UV stability.

Silicone and acrylic render systems are proven solutions for finishing external wall insulation projects. They combine energy efficiency with modern aesthetics, ensuring that properties are protected, attractive, and compliant with UK standards.

Whether you prioritise the long‑term durability and self‑cleaning properties of silicone or the affordability and colour flexibility of acrylic, both systems deliver outstanding results. By choosing the right render system for your project, you can achieve a façade that is not only visually appealing but also built to last.

👉 Ready to upgrade your property with a high‑performance render system? Contact us today to request a free consultation and discover which option is best for your project.