Building aggregates are stones, gravel, and sand used for construction and landscaping. They can be used as a base layer to increase stability or mixed with cement to create concrete and mortar for bricks. Aggregates vary in size, sharpness, and strength, which is why each material has specific applications.
These are the most popular building aggregates used by tradespeople and DIY enthusiasts in the UK:
Ballast is a mix of stones, gravel, and sharp sand. It is most frequently used to create strong, general-purpose concrete when mixed with cement and water. Using ballast saves time as there is no need to measure out the correct amount of sand and stone.
Sharp sand is coarse, angular sand that is used to create concrete and as a base for patios and driveways. It has larger grains that are heavier than other types of sand. These grains interlock to create a strong bond.
Building sand is soft sand that is primarily used to create mortar for bricklaying. Its smooth particles enable a smooth, aesthetically pleasing finish to be achieved. This type of sand is also known as masonry sand and bricklayer’s sand.
Kiln Dried Sand
Kiln-dried sand, which is also known as silver sand, is fine, dry sand that is brushed into the joints of block paving. This helps keep pavements level and free from weeds. Homeowners with artificial grass also often use it as a topdressing.
Horticultural sand is washed, coarse sand that is used to improve soil drainage. It is made from crushed granite, quartz, and sandstone and is free from salt and lime. This type of sand is also referred to as horticultural grit.
Not to be confused with regular ballast, rail ballast is a larger aggregate made from granite. It is used on railway tracks to provide a strong, stable base that helps distribute the weight of passing trains. These stones measure between 30-50mm.
Aggregates are natural building materials and are typically extracted from quarries or collected from sea beds. In some cases, aggregates are made from recycled construction materials, which helps reduce the strain on natural resources. They are the most mined minerals in the world and it is estimated that the UK alone uses 250 million tonnes every year. 90% of this usage is accounted for by the construction industry. Merchants typically supply aggregates in 25kg bags or bulk bags, which contain approximately 800kg.