What is exposed aggregate concrete?
Exposed aggregate concrete is a decorative finish that reveals the natural textures of embedded stones and materials. The process involves removing the surface layer of cement paste to expose the aggregates beneath, creating a textured, slip-resistant surface. Boral’s exposé® range is designed to highlight the beauty of Australian-sourced stone, offering a durable and visually appealing solution for outdoor spaces like driveways, patios, and pool surrounds.
How much does exposed aggregate concrete cost?
The cost of exposed aggregate concrete depends on factors such as location, mix type, project size, and delivery requirements. Boral’s pricing includes a national transport charge per cubic metre, with slight regional variations. For an accurate estimate, it's best to contact your local Boral team or use the online quote form to get a tailored price based on your project specifications.
What are the benefits of exposed aggregate concrete?
Exposed aggregate concrete offers a combination of durability, aesthetic appeal, and practicality. Its textured surface provides excellent slip resistance, making it ideal for high-traffic and wet areas. The finish is low maintenance and naturally camouflages dirt and wear over time. With a wide range of colours and aggregate types available, it can be customised to suit both residential and commercial designs. Boral also offers sustainable options like ENVISIA® low-carbon concrete, adding environmental value to your project.
How is exposed aggregate concrete made or installed?
The installation process begins with pouring a concrete mix that includes selected aggregates. Once the concrete is placed and partially cured, the top layer is removed using techniques such as washing, brushing, or applying a surface retarder. This exposes the embedded stones and creates the final textured finish. The surface is then sealed to enhance durability and protect against staining. Professional installation is recommended to ensure the best results and longevity.
How do you maintain exposed aggregate concrete?
Maintaining exposed aggregate concrete is relatively straightforward. Regular cleaning with water and a mild detergent helps keep the surface looking fresh. Sealing the concrete every few years protects it from moisture, stains, and wear. Avoid using harsh chemicals or high-pressure washing, as these can damage the surface. Periodic inspections for cracks or wear will help extend the life of the concrete and preserve its appearance.
Why does exposed aggregate concrete crack, and how can it be prevented?
Cracking in exposed aggregate concrete can occur due to factors like excess water in the mix, rapid moisture loss during curing, or poor joint placement. To minimise the risk, it's important to use proper curing techniques, such as applying evaporation retarders and maintaining moisture for at least seven days. Avoid placing concrete during extreme weather conditions and ensure joints are correctly positioned to control natural shrinkage.
What causes efflorescence in exposed aggregate concrete, and how can it be removed?
Efflorescence appears as a white, powdery residue on the surface and is caused by water-soluble salts migrating through the concrete. It’s often triggered by moisture movement and can be removed using mild acid solutions, such as diluted vinegar or commercial efflorescence cleaners. Brushing and rinsing the surface can also help. Applying a quality sealer after cleaning will reduce the likelihood of recurrence.
How long does exposed aggregate concrete last?
When properly installed and maintained, exposed aggregate concrete can last for decades. Its durability makes it suitable for both residential and commercial applications. Regular sealing and protection from harsh chemicals or heavy impacts will help preserve its structural integrity and appearance over time.
Where can exposed aggregate concrete be used?
This finish is versatile and well-suited to a range of outdoor applications. It’s commonly used for driveways, walkways, patios, pool surrounds, and landscaping features. Its slip-resistant texture and natural aesthetic make it a popular choice for both private homes and public spaces.
Can exposed aggregate concrete be customised or matched to existing surfaces?
Yes, Boral offers extensive customisation options. You can choose from a wide selection of aggregate types, colours, and finishes to match existing surfaces or create a unique look. The Colori® range allows for colour matching, and Boral’s team can help you select the right mix to suit your design and performance needs.
Why is the exposed aggregate colour range different in each region?
Boral’s exposed aggregate colour range varies by region because we source aggregates from our local quarries. This approach ensures the colours reflect the natural materials native to each area, creating a sense of place and harmony with local architecture and landscaping. Using locally sourced stone also helps minimise transport costs and reduce environmental impact, supporting more sustainable construction practices.
