EWI THIN COAT RENDER

Thin coat render is an especially formulated colored trough ‘one-coat’ product that provides a decorative and protective finish to EWI systems. It comes either in 1mm,1.5mm, 2mm or 3mm textured grain. However, 1.5mm grain is most popular in the UK. The colour of the thin coat render is consistent throughout. It means if you apply it right from the base coat to the surface, it will have a nice even colored texture. It also means you can have a render color of your choice. When applied, it will give you uniform weatherproof finish. It is the most durable render, suitable for use in heavily exposed areas prone to damage. It comes in wet form pre-mixed in 25kg buckets and it is available in a wide range of colors. Thin coat renders, applied at a thickness of 1-3mm onto a flexible basecoat layer, usually leave a textured, slightly grained type finish. This means that a bucket of thin coat render will go far further in terms of coverage than a bag of monocouche scratch coloured render when applied to the wall. They are generally termed as ‘thin coat renders’ because they’re applied in a very thin layer on top of a reinforced basecoat and have the advantage of being especially crack-resistant.

TYPES OF EXTERNAL WALL INSULATION RENDER | GRAINS

Generally speaking they are three types of renders that can be used within a EWI system either on Expanded Polystyrene (EPS), Mineral Wool and Phenolic Resin boards. Some renders have different characteristics than the other. When you choose the renders you should choose one that will best suit your home. Acrylic Render, Silicone Silicate Render and Silicone Render are all examples of coloured renders.

SILICONE RENDER     

Silicone Render is a flagship silicone-based render. One of the most distinct advantages of silicone render is the fact that it’s hydrophobic feature –  it’s a self-cleaning render. They are also very flexible and adaptable given its unique properties such as breathability, hydrophobicity and vapour permeability. Renowned for being long lasting and aesthetically pleasing, this render is the classic choice for homeowners and businesses alike. With hydrophobic properties, the Silicone Render also increased resistance to biological growth. It’s a customer favourite because once it’s installed it requires minimal upkeep and continues to look fantastic. Silicone external renders have gained the most popularity in recent years since it offers so much more than the more traditional solutions. It can be applied to both Rockwool mineral wool and EPS polystyrene.

SILICONE SILICATE RENDER

Silicone Silicate Render is the most popular hybrid silicone render, offering great performance and great value. Silicone Silicate is fantastically versatile, providing the key benefits of a thin coat render with the added boost of self-cleaning and breathability that the silicone technology provides. Silicone Silicate is perfect for a standard classic finish that will maintain its brilliance in the long term. It is a preparation with excellent resistance to biological corrosion, hence it will be recommended for the facade of buildings insulated with mineral wool or grey/white polystyrene, located near forests and water reservoirs.

 ACRYLIC RENDER

Acrylic Render is the best value render. It is impact resistant and is most well known when it comes to coloured render as it retains the colour pigment even after extended exposure to UV. Acrylic Render achieves a vibrant, stand out finish. This is the perfect render if strength, crack resistance and long-lasting colour are key priorities, however it is characterized by low vapor permeability and high tightness, so we do not recommend it for facades insulated with mineral wool.

GRAINS | COVERAGE

Below are the coverage rates you can expect from each grain size:

• 1.0mm = 12m² – 13m²
• 1.5mm = 9m² – 10m² 
• 2.0mm = 7m² – 8m²
• 3.0mm = 5m² – 6m²

THIN COAT RENDER APPLICATION 

Thin coat render can be applied to smooth, dry and clean substrates free from grease, bitumen, dust and other substances decreasing adhesion. Any excess render should always be removed. The whole content of the container should be carefully stirred. If the need appears, add no more than 1% of clean water and mix again. It is quite runny material so don’t overload your hawk when you are putting it on. Product should be evenly applied on the substrate at the thickness of the grain by means of a steel long float held at the angle. Then, it should be given a homogenous structure with round movements by means of a plastic long float flatly held to achieve the appearance of densely laid out aggregate grains structure. Once applied to the thickness of the aggregate, it will be very easy to finish the render using a flat plastic float. Rubbing the render in small circular motions, and during this removing the fat from the render and continuing to smooth down. If the finishing feels very sticky you have applied the render too thick and need to remove the excess so that the render is on very tight.

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Video credit:https://www.youtube.com/watch?v=N1juCG6adcI&t=205s