Colour can play an important part in the identity of any building. Here, Elissa Turnbull from Saint-Gobain Weber shares her tips for specifying render
From the brightly colourful houses rendered in Portobello Road, to the traditional Suffolk Pink, colour can play an important part in the identity of a home or building. Compared to some traditional building materials and finishes, rendering can be a cost-effective way to achieve a desired aesthetic.
The versatile nature of render, combined with the range of colours and finishes available, means that it can be used on most properties, no matter the location, to create a home that stands out.
But before choosing the colour, you need to consider what type of render to use. Mineral finishes like monocouche render are created using natural pigments, so the colours will be prescribed by nature – think pastels and earth tones. For something brighter, opt for synthetic products, such as silicone-enhanced textured finishes and paints.
When specifying render, engage with the system manufacturer early in the process as they are best placed to understand how their products can achieve the project’s goals and can help with recognising any constraints that will impact how the project looks.
Coloured render & fire performance
Achieving different colours requires different levels of organic content in the render, and organic content is combustible. Light colours like white or cream need less organic content, and in the past, some manufacturers might only have fire tested those colours because they were most likely to pass. Such an approach is clearly not in the spirit of the culture of product safety that’s now required.
You should ensure that manufacturers have an appropriate range of colours tested – especially reds and yellows, which tend to have the most organic content.
Be particularly careful, however, if you are thinking of specifying a non-standard colour for your project. Manufacturers are unlikely to be able to support specific testing of it, due to prohibitive costs for a single project.
Coloured render & heat & light performance
Something else to look for is the light reflectance value of the colour being considered. A renders ability to absorb heat influences how it will perform in the long term. Dark colours absorb more heat and are at increased risk of potential cracking compared to light colours.
A render’s ability to absorb heat influences how it will perform over the long term.
The importance of detailing
Render systems are traditionally low maintenance but, like any other building facade, they are not immune from the gradual buildup of organic growth and dirty deposits.
To avoid any staining on the render, architectural considerations such as drainage, natural water flow and splash zones need to be made. For example, keeping render 150 mm above ground level will reduce any discolouration from splashing, and generous overhangs are also recommended to both protect the top edge of the render and prevent staining.
To help keep the finish looking fresh for longer, consider extending eaves and window sills to address water run-off.
Ashlars, raised bands, string courses, keystones, quoins and plinths can all be created through the use of thick coat render systems or by building up or cutting back insulation to create these embellishments.
Considerations
It’s always a good idea to remain sympathetic to surroundings and location. For example, developments in coastal regions are at much greater risk of exposure to aggressive weather than inland regions. Applying render can help protect and decorate buildings in these highly exposed areas.
Properties in areas close to busy roads will suffer from the effects of traffic pollution, which can leave a dark residue or cause discolouration on external surfaces.
To stop the pollution penetrating the facade, a protective coating could be used to create an additional barrier. Using a highly hydrophobic coating protects render from water ingress, oil and graffiti, as well as dirt, stains and other atmospheric contaminants.
Adding this type of coating does not affect the original appearance of the render and still allows the substrate to breathe. It simply helps to keep render looking better for longer.
Try before you buy
Envisaging how your building will look can be a difficult task, especially when you consider other external features such as doors and windows. Designers and applicators can use a colour facade simulator, such as the one we offer, which is able to show customers exactly how different renders and decorative finishes would look on their building by uploading a photo of the property or using one of the templates.
Specifying a rendered facade enables architects to achieve design goals, enhance visual appeal, and address practical considerations in a cost-effective and versatile manner.
Elissa Turnbull is product marketing manager at Saint-Gobain Weber