A Guide to the Different Types of Aggregates & Their Uses
Aggregates are materials that have been used in construction for hundreds of years. They are an essential component of concrete and asphalt and are commonly used in heavy-duty projects, such as in base layers for roads and foundations for buildings. They are also widely used for domestic and DIY projects too. Whether you need a decorative feature or finish in your garden and driveway, bulk bagged aggregates or loose aggregates are an inexpensive choice, really easy to work with, and they certainly help you reduce the time you spend on property upkeep.
Aggregates come in different gradings, and textures, with varying moisture content and various other characteristics that determine the kind of job they are suited for. Let’s look at different types of aggregates and some of their uses so you can make the best choice for your next project.
Aggregates by Size
Sand
Sand is the most basic form of aggregate. It is created by natural erosion or quarried from a seam. Colour can vary, but it is usually cream, brown, or grey. As a fine aggregate, sand can be used to fill the voids where other coarse aggregates are also being used.
There are different types of sand available for construction: sharp sand, ballast, and even recycled sand. Each type has its own uses. Sharp sand tends to be used for mixing concrete or for jobs like laying paving slabs. This is because it has the largest grains and can provide a strong bed for other material to sit.
Ballast Sand
Ballast is a mix of sand and gravel and is generally used when building foundations for specific jobs such as houses and roadways as well as railways. The reason for this is that it’s heavy enough to provide a stable base and stop the structure from moving, but not so heavy that it limits drainage. Keep reading to find out the difference between sharp sand, ballast sand and recycled sand.
Gravel
Gravel has larger grains than sand. It can be used as part of driveways or pathways, occasionally mixed with concrete but often simply laid down on top. Gravel is also a great mulch substitute. Mulch can still allow weeds and grass to grow in your flower beds, while gravel lets you maintain a good-looking landscape year-round with less upkeep.
Rocks, pebbles and shingle
These types of aggregate come in a variety of colours, shapes, and surface textures. Shingle and stone aggregate can be glassy, smooth, rough, honeycombed, and more, and can be used to create unique and beautiful decorative garden features.
Crushed rock
One particular type of aggregate is crushed rock, made when larger pieces of rock are crushed into smaller pieces. This makes for another excellent base for forming concrete slabs and driveways.
Recycled and Repurposed Aggregates
Recycled sand
Recycled sand is environmentally friendly because it isn’t newly quarried but instead often comes from construction work such as washing away old concrete or masonry. It still has plenty of uses and can be used in mortar mixes or on top of block paving to create a strong level finish.
Recycled concrete
Using recycled concrete is a great way to save on costs and opt for the more environmentally friendly option. Recycled concrete has been crushed into gravel size chunks (see DOT type 1 below), which makes it perfect for use as a base layer.
Rock dust
Fine rock dust is a by-product of the quarrying industry and results from rock crushing. Also known as crusher dust, it can be used to improve the soil by remineralization, helping to rebuild topsoil and to speed up growth in your garden.
Sub-Base Aggregates
Sub-base aggregates can be made of primary rock limestone or recycled concrete, the most common type. Sub-bases are the load-bearing layer of many pavements providing their strength and resilience. The most used sub-base is type 1, also known as MOT type 1 or DOT type 1. It ranges in size from 63 mm down to dust and most of the material is typically at 31.5mm and smaller.
Loose and Bagged Aggregate Services in Surrey & Sussex
With over 20 years experience in the industry, Axtell provide loose or bagged aggregates in various sizes and forms to fit your exact project requirement. With a flexible delivery schedule around Guildford, Farnham, Godalming, and the wider Surrey & Sussex area, we can deliver bagged aggregates for smaller domestic projects or loose aggregates in bulk delivery for larger projects. Get in touch with a member of the team today on 01483 399007 to get a quote or find out more about our aggregate delivery services.
Alternatively, if you know the type of aggregates you require, use our aggregate calculator to estimate how much you’ll need for your project.
