What Is Rendering?

If you are renovating the outside of your home, you may have come across the term rendering. But what is rendering, what does it actually do and which type of render should you choose?

Rendering is the process of applying a protective and decorative coating to the outside walls of a property. It can give tired or uneven walls a completely new appearance while also providing an additional layer of protection against the weather.

There are several different types of external render available, from traditional thicker renders to modern thin-coat silicone systems. The right option will depend on your property, the existing wall and the finish you want to achieve.

In this guide, we explain what rendering is, why houses are rendered and the main types of render available.

What Is Rendering?

Rendering is the process of applying a specialist coating to an external wall.

The material applied to the wall is called render, while rendering describes the overall process.

Depending on the system being used, rendering can involve several layers rather than simply applying one coat directly to the wall. A modern render-only system, for example, can include a reinforced basecoat, fibreglass mesh, primer and decorative topcoat. 

Once complete, the render forms the visible external surface of the property.

Rendering can be used to:

• Refresh the appearance of an older property

• Cover tired or uneven masonry

• Create a more modern exterior

• Protect suitable external walls from weather exposure

• Add colour and texture to a façade

• Finish an external wall insulation system

Why Do People Render Their Houses?

One of the main reasons homeowners choose rendering is to improve the appearance of their property.

Older brickwork, previous repairs and different building materials can sometimes leave an exterior looking inconsistent. Rendering can create a much more uniform finish across the façade.

But rendering is not only decorative.

A correctly specified external render system also forms a protective surface over the wall. Modern systems can offer properties such as water repellence, breathability and increased resistance to cracking, depending on the render selected. 

What Does a Rendered House Look Like?

Rendering can dramatically change the appearance of a home.

Instead of exposed brick or blockwork, the property has a continuous rendered surface. Depending on the product, this can range from a relatively smooth finish to a much more textured appearance.

Colour is another major consideration.

Many modern renders are available pre-coloured or can be tinted, removing the need to rely on a painted finish to achieve the colour you want.

For example, EWI-075 Silicone Render is available in a wide selection of colours and grain sizes ranging from fine to more textured finishes. 

 

What Are the Different Types of Render?

There is no single type of render that is right for every house.

Some of the main options you are likely to come across include silicone render, monocouche render and mineral render, alongside other specialist finishes.

Silicone Render

Silicone render is a modern thin-coat render that is particularly popular for residential properties.

It is typically supplied ready mixed and applied as the final decorative layer over a prepared reinforced basecoat.

Silicone render is designed to be:

• Breathable

• Flexible

• Hydrophobic

• Durable

• Available in a wide range of colours

• Available in different textures

Its flexibility can help it cope with small amounts of movement within the system, while its hydrophobic surface helps repel water. 

Silicone render can be used as part of both a render-only system and an external wall insulation system when the correct build-up is followed. 

Explore Silicone Render

Monocouche Render

Monocouche render is a thicker, cement-based render.

Unlike a thin-coat silicone finish, monocouche is applied at a greater thickness and is finished by scraping the surface to create its characteristic textured appearance.

It is through-coloured, meaning the colour runs through the render rather than simply sitting on the surface. Our EWI-090 Monocouche Render is available in a selection of colours. 

Monocouche is a good option for homeowners who prefer the more traditional appearance of a thicker scraped render.

Mineral Render

Mineral render is another thin-coat option.

EWI-060 Mineral Render is supplied as a powder and can be applied as part of an external wall insulation or suitable render-only system. Unlike ready-coloured silicone render, it needs to be finished with an approved external silicone masonry paint. 

This creates a different installation process but allows the final painted colour to be chosen separately.

What Is the Difference Between Silicone Render and Monocouche?

This is one of the most common comparisons homeowners make.

The biggest difference is the type and thickness of the finish.

Silicone render is a thin-coat, ready-mixed decorative finish. It provides a modern textured appearance and offers properties such as flexibility, breathability and water repellence.

Monocouche render is a thicker cement-based render that is applied and then scraped back to create its finished texture. We describe monocouche as producing a smoother, chalkier scraped appearance compared with silicone thin-coat render. 

Neither is automatically right for every property. The choice will depend on the existing wall, the required system and the appearance you prefer.

Is Rendering the Same as Plastering?

Not quite.

Although both involve applying a material to a wall, they are generally used in different places.

Plastering normally refers to creating a smooth finish on internal walls and ceilings.

Rendering generally refers to applying a protective and decorative finish to external walls.

The products are also formulated differently because external render needs to cope with rain, changing temperatures and other outdoor conditions.

Can You Render Over Brick?

Yes, render can be applied over suitable brickwork, but the wall needs to be assessed and prepared correctly first.

The correct preparation will depend on the condition of the bricks and the render system being installed.

A typical modern render-only build-up can include:

Brickwork → Basecoat → Fibreglass Mesh → Primer → Decorative Render

The basecoat and mesh create a reinforced layer beneath the final finish. 

Poor, loose or heavily damaged backgrounds may require additional preparation before rendering begins.

Can You Render Over Blockwork?

Yes. Blockwork is another common background for external render.

As with brick, it is important to use a compatible system rather than simply applying the final decorative render straight onto the wall.

We have dedicated buyer's guides for both rendering onto brick and rendering onto blockwork, which outline the products required for the complete build-up. 

Does Rendering Insulate Your House?

Render itself should not be confused with insulation.

Rendering can improve the appearance and weather protection of the outside of a home, but a standard render-only system does not provide the same thermal upgrade as an external wall insulation system.

If improving the thermal performance of your walls is the main objective, insulation boards can be installed to the exterior first and then covered with a reinforced render system.

A typical external wall insulation build-up includes insulation beneath the basecoat, mesh, primer and final render. 

This allows the property to benefit from both insulation and a new rendered appearance.

What Is a Render-Only System?

A render-only system is used where you want to render the property without adding external wall insulation.

A typical system can include:

1. Preparation of the existing wall

2. Basecoat

3. Fibreglass mesh

4. Primer

5. Decorative render

Exactly what is required will depend on the substrate and chosen finish.

The important thing is to treat the products as a complete, compatible system rather than choosing the decorative render without considering what needs to go underneath it.

Explore Render Systems at EWI Store

What Is Rendering with External Wall Insulation?

Rendering is also the final visible stage of many external wall insulation systems.

Instead of applying the render build-up directly over the existing wall, insulation boards are first fixed to the outside of the property.

A typical build-up may include:

Existing wall → Insulation → Basecoat and mesh → Primer → Decorative render

Once complete, the insulation is hidden beneath the rendered façade.

This means a homeowner can improve the thermal performance of the external walls while also completely changing the appearance of the property. 

Does Render Come in Different Colours?

Yes, although the colour options depend on the type of render you choose.

Modern silicone renders provide particularly wide colour choice. EWI-075 Silicone Render, for example, can be tinted in thousands of colours and is available in several grain sizes to create different textures. 

When choosing a render colour, it is worth looking at a physical sample rather than relying entirely on a computer or phone screen.

Colour can look different depending on:

• Natural daylight

• Time of day

• Surrounding materials

• Render texture

• Size of the finished area

Testing a sample against the property can make choosing the final colour much easier.

What Render Texture Should You Choose?

Render does not have to be completely smooth.

With thin-coat silicone render, the grain size determines how fine or textured the finished surface appears.

Smaller grains create a finer appearance, while larger grains make the texture more noticeable.

EWI-075 is currently available in grain sizes including 0.5mm, 1mm, 1.5mm, 2mm and 3mm. 

For homeowners, choosing a render is therefore as much about texture as colour.

Can You Render an Old House?

Potentially, yes, but older properties need to be considered carefully.

The existing wall construction, condition of the substrate and way the building manages moisture can all influence which render system is appropriate.

Simply covering an older wall with whichever render is cheapest may not be the right approach.

For traditional buildings in particular, more breathable materials such as suitable lime-based systems may need to be considered.

If you are uncertain about the construction of the property, it is worth getting advice before choosing the render.

What Do You Need to Render a House?

The render itself is often only one part of the project.

Depending on the wall and chosen system, you may also need:

• Basecoat

• Fibreglass mesh

• Render beads

• Primer

• Mechanical fixings

• Render tools

• Protective materials

• Decorative render or paint

Our render systems are designed around complete build-ups, helping you identify the products required beneath the final finish. 

Which Type of Render Should You Choose?

The right render depends on both the property and the finish you want.

You may prefer:

• Silicone render for a modern, flexible, breathable and hydrophobic thin-coat finish

• Monocouche render for a thicker, traditional scraped appearance

• Mineral render for a thin-coat mineral finish that is subsequently painted

• A more specialist system where the property or substrate requires it

Before buying, consider the existing wall, whether insulation is being installed, the required finish and the complete system underneath the render.

Where Can You Buy Render?

We supply complete rendering systems for homeowners, installers and contractors, including basecoats, fibreglass mesh, primers, beads and decorative finishes.

You can browse the full range of Render Systems at EWI Store or use the our buyer's guides to find the materials required for a particular wall or insulation type. 

So, What Is Rendering?

Put simply, rendering is the process of applying a protective and decorative finish to the exterior walls of a property.

It can transform how a house looks, help protect suitable exterior walls and form the final finish of either a render-only or external wall insulation system.

The important part is choosing a render system that suits the property rather than focusing only on colour or appearance.

Once you understand the existing wall and the finish you want, you can choose from options such as silicone, monocouche and mineral render and build the correct system underneath it.