Choosing the correct aggregate is crucial for the success and longevity of any construction project.
Aggregates play a vital role in providing strength, stability and durability to structures, whether you’re building roads, laying foundations, or completing landscaping projects.
With so many options available, such as quarried, recycled, sand, gravel and more, it’s essential to select the right material for your specific application.
This guide will help you make an informed decision by covering the basics on types of aggregates, their uses, and factors to consider when choosing the best one for your project.
Aggregates come in different types and forms, with each serving a specific purpose in construction.
The most common categories include:
Quarried Aggregates
Extracted from natural stone quarries, these materials are ideal for robust and load-bearing applications. Some of these include:
Recycled Aggregates
Sourced from reprocessed materials like crushed concrete or asphalt. These are sustainable alternatives, often used for subbase, backfill, or general construction purposes.
Sand
Different types of sand (Building Sand, Grit Sand) are used for a variety of task such a bedding or backfill or in other applications such as mortar for bricklaying.
Each construction project will have unique requirements requiring different aggregates.
Here are some considerations based on common applications:
Subbases and Foundations
For stable foundations and subbase layers, you’ll want strong, angular aggregates like Type 1 subbase or 6F5 Crushed Rock.
These materials offer excellent compaction and load-bearing properties, making them ideal for roads and heavy structures.
Pipe Bedding and Drainage
In drainage applications, clean aggregates with the fines removed like 10mm or 20mm pipe bedding are preferred.
40mm Clean or 75mm Clean can be used for larger drainage projects or subbase under permeable surfaces.
Backfilling and Capping
When you need to fill voids or create stable surfaces, you could select something like a fill sand.
Topsoil is often used for capping where vegetation will be grown.
Erosion Control
When dealing with coastal, riverbank, or steep landscape area prone to erosion, specific aggregates are needed to protect against the impact of water.
Larger aggregates like Riprap and Rock Armour are ideal for stabilising shorelines, flood-prone areas, and embankments. These large, angular stones create a strong barrier against moving water making them perfect for erosion control and flood defences.
The size of the aggregate can directly affect its overall performance in various applications.
Smaller are better suited to applications such as creating bedding layers because they can produce stable surfaces.
Larger aggregates are more suitable for erosion control, sub-base layers or load bearing applications.
In some cases, aggregates may need to meet certain technical specifications to ensure they comply with building standards. These include:
Grading
Aggregates must meet specific size distribution requirements to ensure proper compaction and load distribution.
Strength and Durability
This can be important in load bearing areas and aggregates may need to pass compaction test.
Frost Resistance
In areas exposed to freezing conditions, you may need aggregates with frost resistance properties.
With the growing emphasis on sustainability, many construction projects are opting for recycled aggregates.
These materials help reduce the environmental impact by diverting waste from landfills and minimising the need for quarrying new materials.
If your project has sustainability goals, recycled materials are a great alternative for subbases and backfill.
When selecting aggregates, also consider the logistics of getting the material to your site.
Factors such as access, areas for unloading and the type of project can influence your choice. For example:
Bulk Deliveries
For large projects, you’ll need bulk deliveries of aggregates, typically transported via tipper trucks. Ensure the delivery company can accommodate your site’s specific requirements
Small Projects
For smaller job, you might opt for bagged or smaller quantities that can be more easily transported and handled.
If you’re still unsure about the right aggregate for your project, it’s always a good idea to consult with suppliers of industry professionals.
They can provide guidance on materials that meet your budget, timeline and specific construction needs.
Be sure to discuss the project’s scope, environment, and any specific concerns you have regarding load, drainage, erosion or sustainability.
Call: 0161 647 7409
Email: info@gmat.co.uk
Get In Touch HERE
...It Shouldn't Cost The Earth
