Limestone Calculator
Need crushed limestone for a driveway, base layer, or drainage project? Enter the area and depth to find out exactly how many cubic yards and tons to order.
Understanding Limestone Types and Sizes
Crushed limestone comes in a range of sizes, each suited to different applications. The numbering system refers to the stone size after crushing. Smaller numbers mean larger stones. A #57 stone is about 3/4 inch in diameter, while #8 is roughly 3/8 inch.
Limestone screenings, also called limestone fines, are the powdery residue left after crushing. Mixed with larger stones, they create a material that compacts tightly, making it ideal for driveways and pathways. Pure screenings pack down hard but can turn muddy when wet.
For drainage applications, stick with clean, washed limestone in larger sizes. The voids between stones allow water to percolate through. Avoid screenings or fines in French drains and foundation backfill, as they clog and reduce water flow.
Limestone for Driveways and Paths
Limestone driveways offer a rustic look and excellent compaction at a lower cost than asphalt or concrete. Start with a 4 to 6 inch base layer, then add 2 inches of finer material on top for a smooth surface. The base should be larger stones like #57, while the top layer can be #411 or screenings.
Preparation is critical. Remove all organic material and soft soil first. Compact the subgrade, then spread your limestone in layers. Compact each layer before adding the next. Skipping compaction leads to ruts and low spots within months.
Expect to add a thin layer of fresh limestone every few years. Traffic and weather wear the surface. A light top-dress of screenings every other year keeps the driveway looking sharp and prevents potholes from forming.
Calculating Limestone for Your Project
Volume calculations follow the same pattern for all aggregate materials: area times depth. The trick lies in converting inches to feet and feet to yards. This calculator handles that conversion automatically, so you get cubic yards and tons without manual math.
Limestone's weight per cubic yard varies slightly depending on stone size and moisture content. Dry, coarse limestone weighs about 1.3 tons per yard. Damp, finely crushed limestone with screenings can reach 1.4 tons per yard. Using 1.35 tons per yard as an average keeps estimates close to real-world deliveries.
Always order 10% extra. Irregular terrain, compaction, and spillage during spreading mean you will use more than the pure mathematical volume. Running short on the last section of a project wastes more money in delivery fees than the cost of a small overage.
Frequently Asked Questions
How much does crushed limestone weigh?
Crushed limestone weighs approximately 1.3 to 1.4 tons per cubic yard. Larger stones weigh slightly less per yard than finely crushed material.
What is the best depth for a limestone driveway?
A stable driveway needs 4 to 6 inches of compacted limestone. Use 4 inches for light car traffic and 6 inches for heavier vehicles or areas with soft soil.
Can I use limestone for drainage?
Yes. Larger crushed limestone (often called drainage stone or #57 stone) allows water to flow through while providing a stable base. Do not use limestone screenings for drainage.
What size limestone should I order?
Common sizes include #8 (3/8-inch), #57 (3/4-inch), and #411 (crushed with fines). Choose #57 or larger for drainage, #411 for compacting driveways.
Do I need to compact limestone after spreading?
Absolutely. Compacting with a plate compactor or roller increases stability and prevents shifting. Compact in lifts no thicker than 4 inches for best results.