Different types of aggregates can be used in different applications for construction and landscaping. You may need to use different criteria when selecting aggregate for different projects. Here are some tips for how to identify a good aggregate for different types of projects.
Aggregate for pathways and driveways
When choosing a product to make pathways or driveways, you'll want to avoid aggregates that break down easily under pressure (such as brittle types of stone) since those will have a shorter life and need to be replaced more often. This is especially important if you're making a gravel driveway since cars can place a lot of pressure on the aggregate. Crushed granite is one example of a material that will hold up well because it's so durable.
In addition, you'll want to avoid aggregates that have smooth rounded edges (such as river rock and pea gravel). These aggregates tend to escape more easily around the edges and offer less traction when driving. A crushed aggregate with corners and edges that don't slide against each other so easily allows better driving traction.
Aggregate for mulch
In many cases, homeowners may want to use aggregates such as crushed stone or lava rock for garden bed and landscape mulches. When choosing an aggregate for a mulch, you'll want to look for an attractively colored aggregate and something that allows water to flow through easily but help keep down weeds.
In most cases, you'll want an aggregate with smaller-sized pieces (such as pea gravel rather than a large river rock or quarry spalls) for a mulch. The smaller pieces have smaller gaps, which means sunlight can't reach the ground easily and weeds are blocked more effectively. In addition, larger rocks can be heavy and could cause damage if applied around delicate bedding plants.
Lava rock is often a popular choice for stone mulch because it's not only attractively colorful but also lightweight. Its weight means it's easier to handle and haul, but also means it doesn't compress the soil in your landscape beds.
Aggregate for drainage
If you're using aggregate in a drainage project, it may have different requirements. For example, if you're using aggregate to fill in a dry well or to bed pipes for a French drain, you'll want aggregate that's as well-drained as possible. For this reason, you'll want to look for dust-free aggregate that has large pieces because this creates larger air spaces in between.
As you can see, you may need to use different criteria when shopping for aggregates for these common projects. If you're unsure what type of aggregate you need, get in touch with your local contractor or aggregate provider in the area to discuss different options.