AASHTO #1 crushed stone is the largest of the stone classes, making it a versatile option for many large-scale construction projects. Also referred to as PA #4 ballast, this aggregate is commonly used for road bases, construction entrances, and seepage pits. It is a clean material that will not compact.
The American Association of State Highway and Transportation Officials (AASHTO) classifies stones based on certain characteristics. The size of these stones helps determine the best application for each type to save on costs while effectively completing projects.
Available at these locations:
Bonnybrook Quarry Map it
Lincoln Quarry Map it
Shrewsbury Facility Map it
Crushed stone is a sustainable resource because it can be produced using nearly any kind of hard rock. At York Building Products, we use Pennsylvania’s abundant source of limestone to create AASHTO #1 and other grades of crushed stone.
People frequently use crushed stone for maintenance and road construction applications, but you can also use some crushed stones to create lime, cement and similar agricultural materials.
Differing grades of crushed stone are categorized based on the size of the pieces generated by the crushing process. The stone’s size will determine whether the best applications will be construction and landscaping projects or decorative ones, such as lining for residential ponds to stormwater diversion pits. #1 crushed stone is the largest grade.
York Building Products offers type 1 aggregate in the Central Pennsylvania region.
Crushed stone products are very versatile as there are many sizes to choose from, each with distinct application purposes. Crushed #1 stone is the largest of the crushed stone grades, making them excellent for jobs needing to fill ample space. The need for type 1 stone (or other types) varies by project.
Each stone class ranges in size. Typically, the higher the class number, the smaller the stone size. Finding the right crushed stone size is essential for project completion because each has a different capability and purpose, and some projects may call for multiple types.
For example, you would avoid large crushed stones for a commercial walkway because this would create a challenging surface to walk upon.
See how Class #1 stone compares to similar crushed stone types with these examples:
AASHTO #1 has a top rock size of 2 to 4 inches. These crushed stones are bulky, and their size makes them impractical for surfacing material uses. However, AASHTO #1 is excellent for subgrade stabilization. It is a clean material that won’t compact, allowing for many construction applications.
AASHTO #1 is the largest crushed stone variety offered by York Building Products.
The most common types of rock used in crushed stone production are limestone, granite, and quartzite. However, you can also use slate, marble, sandstone and volcanic cinder for some construction applications. After mining these materials, they are crushed into specific sizes for a wide array of practical uses.
As the largest crushed stone grade available, AASHTO #1 is naturally suited for larger jobs. It’s excellent for creating a sub-base layer to evenly distribute weight over a specific area to improve heavy carry loads.
Unlike fine or coarse aggregates, AASHTO #1 aggregate is unsuitable for small-scale applications such as creating asphalt or concrete mixes or providing a foundation. These stones are excellent ballast materials for railroad sites and similar locations, which is why this stone is commonly known as PA #4 ballast.
Here are some common commercial and residential applications for materials of this grade:
The bulky size of AASHTO #1 makes it suitable for lining diversion pits for stormwater. These stones allow water to bypass and seep into the layers underneath, providing more efficient drainage. These stones also make excellent decorative pieces for landscaping around a pond or in similar visual applications, such as lining the edge of walkways.
These stones are great for creating construction entrances and a stabilized road base. You can also use AASHTO #1 stone to line ditches or make a driveway base with screening. Other large jobs, such as culvert ballasts, are also suitable for #1 stone.
If you’re planning on taking on any of these construction projects, AASHTO #1 might be the right material for you. Request a free quote from York Building Products for delivery or purchase in the Central Pennsylvania region.
If you are working on a project and want to know whether AASHTO #1 stone is the right call, the answers below can help. We cover how to know when #1 is the right fit, what it means that it will not compact and other questions.
AASHTO #1 crushed stone is the right choice for your project when you need to fill large voids, stabilize a subgrade or manage stormwater for road bases, construction entrances and seepage pits. If your project calls for a material that will not compact and allows water to pass through freely, #1 is your best option.
#1 crushed stone will not compact because the large stones don’t bind together under pressure, leaving open spaces between them, and that matters for your application because those gaps allow water and air to pass through freely. For seepage pits and drainage applications, that open structure works in your favor. If your project requires a firm, dense base, you will want a compactable option like 2A modified or #10 stone instead.
You can use AASHTO #1 stone as a driveway base instead of choosing a smaller grade, but it works best when paired with a screening layer on top since, on its own, the large stones are not practical as a finished surface. For a complete driveway, many contractors use #1 as the subbase and finish with a finer grade above it for a more workable surface.
The exact particle size range for AASHTO #1 crushed stone runs from two inches to four inches, making it suitable for filling large voids, lining stormwater diversion pits and stabilizing subgrades. When your project calls for a coarse, open structured material that allows water to pass through freely, #1 stone is built to do that job.
AASHTO #1 stone is highly effective for drainage and stormwater management applications because its open structure allows water to flow and seep into the layers below. You will find it used to line stormwater diversion pits and seepage areas where managing water flow is the priority. When your drainage application needs a durable, noncompacting material, #1 stone is a dependable choice.
Having access to a reliable producer of stone, concrete and blacktop can make all the difference when it comes to a successful construction job. York Building Products is proud to provide service from our plants in York and Cumberland counties to the entire Central PA region. In addition, we provide AASHTO #1 stone at our plant in Cecil County, MD. We make safety a priority and offer specialized services that are hard to find at other quarries in Pennsylvania and Maryland.
We have been Central PA’s reliable provider of crushed stone for more than 80 years. We offer AASHTO #1 as part of a wide range of sizes of crushed stone to fit the needs of any commercial or residential construction project you have in mind.
For assistance in finding the best grade of crushed stone for your project, feel free to reach out to us. We deliver to locations throughout Pennsylvania, including Cumberland County, Dauphin County, Lancaster County, Perry County and York County. We also have plants in Maryland and Delaware, empowering us to help local residents in a variety of locations.
Our knowledgeable staff is prepared to assist homeowners, builders and contractors in planning their projects and their budgets. Give us a call at 800-673-2408 or get in contact with us online to speak to a representative about your next project so we can help you find the right grade of stone for your project.
717.771.3507 