Gravel is one of the most versatile and commonly used landscaping materials. It has a wide range of applications, from driveways and walkways to decorative accents in gardens. Knowing how much area a ton of gravel will cover is important for planning and budgeting landscaping projects. The amount of coverage depends on several factors, including the type and size of gravel and the depth it is laid. With some simple calculations, you can get a rough estimate of gravel coverage to help with your project planning.
What is Gravel?
Gravel is a loose aggregate of rock fragments created by the erosion, weathering and abrasion of larger rocks. It typically ranges in size from 2mm to 64mm in diameter. The most common types used in landscaping are:
– Pea gravel – Small stones around 1/4 inch (6mm) in diameter. Often used in walkways, patios and decorative accents.
– 1/4 minus gravel – A mix of stone between 1/4 inch and smaller. Used for driveways, walkways, and drainage.
– 3/8 minus gravel – Stones ranging from 3/8 inch down to fines. An all-purpose landscaping gravel.
– 1/2 inch gravel – Larger stone between 1/2 and 1 inch. Used for drainage and landscaping.
– 3/4 inch gravel – Stone between 3/4 inch and 1 inch. Used for driveways, drainage, and decorative ground cover.
Gravel comes in a range of natural colors like gray, brown, reddish hues, or white. Crushed stone and crushed recycled concrete can also be used as gravel.
Coverage Per Ton of Gravel
The amount of area a ton of gravel will cover depends on the stone size, thickness laid, and whether it is calculated by loose (uncompacted) or compacted coverage. Some key factors:
– Stone size – Smaller gravel takes up less space per ton than larger gravel. A ton of pea gravel will cover more area than a ton of 1 inch gravel.
– Thickness – The thicker the layer of gravel, the less area it will cover per ton. A 2 inch layer will cover half the area of a 1 inch layer from the same tonnage.
– Compaction – When first dumped, uncompacted gravel takes up more area per ton. Once compacted, settled gravel reduces coverage by about 20%.
– Shape – Angular crushed gravel pieces fit together more tightly reducing coverage compared to smooth, rounded river gravel stones.
Loose Coverage Per Ton
When calculating the amount of loose, uncompacted gravel needed, here are some general estimates:
– Pea gravel or 1/4 inch – 100 to 150 square feet per ton
– 3/8 inch gravel – 80 to 100 square feet per ton
– 1/2 inch gravel – 60 to 80 square feet per ton
– 3/4 inch gravel – 45 to 60 square feet per ton
– 1 inch gravel or larger – 30 to 45 square feet per ton
These figures are based on a typical 1 inch layer thickness. To find the coverage for different thicknesses, divide the coverage for 1 inch by the desired thickness in inches. For example, 3/8 inch gravel at 2 inches thick would cover roughly 40-50 sq ft per ton (100/2 = 50 sq ft).
Compacted Gravel Coverage Per Ton
Once compacted down, settled gravel will cover around 15-20% less area per ton. Here are some estimates:
– Pea gravel – 80 to 120 square feet per ton
– 1/4 inch gravel – 65 to 80 square feet per ton
– 3/8 inch gravel – 50 to 65 square feet per ton
– 1/2 inch gravel – 40 to 55 square feet per ton
– 3/4 inch gravel – 30 to 45 square feet per ton
– 1 inch gravel – 20 to 30 square feet per ton
Again, these figures are for a 1 inch layer thickness. Simply divide by the thickness in inches for other compacted depth coverage estimates.
How to Calculate Gravel Needs
Figuring out gravel needs for your project is easy once you know the basics. Follow these steps:
1. Measure the area to be covered in square feet (length x width).
2. Determine depth needed in inches. Most gravel layers are 1 to 2 inches thick.
3. Choose appropriate gravel type and size for the job. Consider traffic, usage, drainage and aesthetic needs.
4. Find the corresponding coverage (sq ft per ton) based on stone size above.
5. Divide area (sq ft) by coverage (sq ft/ton) to estimate required tons.
6. For other depths, divide the inches by depth to get tons needed.
7. Add 5-10% extra for a buffer. It’s easier to have leftover gravel than run short.
Let’s look at an example:
– Area to cover is a 10 ft x 12 ft patio = 120 sq ft
– Desired depth is 2 inches
– 3/8 inch pea gravel selected
– Coverage is about 100 sq ft per ton at 1 inch depth
– At 2 inch depth: 100/2 = 50 sq ft per ton
– 120 sq ft/50 sq ft per ton = 2.4 tons
– Round up to 3 tons with 10% extra
So approximately 3 tons of 3/8 inch pea gravel would be required to cover a 120 sq ft patio at 2 inches deep.
Easy! Following these guidelines will help estimate your gravel needs for any project.
Factors that Affect Gravel Coverage
While the above coverage estimates are reasonable averages, a few factors can affect the actual coverage area per ton of gravel:
Compaction Equipment
Proper compaction makes a big difference in the final compacted density. Light tamping with a hand tamper will compact less than repeated passes with a heavy vibrating plate compactor. Coverage estimates assume moderate compaction with typical landscape equipment.
Angularity of Stone
Crushed gravel with sharp edges and corners fits together better than rounded river gravel, reducing voids. Angular gravel will have up to 20% less coverage per ton than rounded stones.
Variation in Stone Size
Gravel with a wider range of particle sizes can compact tighter than single-sized gravel for less coverage per ton. Gravel with fines will take up less area.
Soil Type
Sandy or loose soils may not compact as well as clay soils, resulting in more settling and space between stones. Consider adding 10% extra gravel by volume for loose, sandy soil subgrades.
Usage
High traffic areas may compact over time, requiring occasional top-ups to maintain depth. Plan for 10-15% extra gravel by volume in driveways or other frequently used sites.
Moisture Content
Both dry and saturated gravel can affect compaction. For best results, add water gradually while compacting to reach an optimal dampness without soaking the material.
Gravel Depths for Different Uses
How deep you need to lay your gravel layer depends on the intended use:
Decorative Gravel Areas
For flower beds, gardens and decorative ground cover, 1 to 2 inches is common. Aim for 1.5 to 2 inches over weed barrier fabric to discourage weeds.
Walkways and Patios
Walkways can be 2 to 3 inches deep, while heavier use patios benefit from 3 to 4 inches over a crushed stone base. Ensure the subgrade is very compact and level first.
Driveways
Driveways require a 4 to 6 inch typical gravel base over soil subgrade, plus a 1 to 2 inch top layer with smaller gravel or crushed stone. Total depths of 6 to 8 inches are common.
Drainage
For drainage swales or trenches, 6 to 12 inches of gravel allows good water flow. Geotextile filter fabric underlay helps prevent soil from clogging the voids.
Erosion Control
On slopes or drainage channels, 3 to 5 inches of larger stone stabilized with landscape fabric helps control erosion issues.
Gravel Delivery and Installation
Once you’ve estimated your gravel needs, the next step is having it delivered. Gravel is sold by the ton and most landscape material suppliers can deliver large orders directly to your site by dump truck. The trucks can also spread and level the gravel where needed. Here are some tips:
– Order 5-10% extra to allow fine-tuning areas and account for any losses, spills or compaction.
– Have gravel dumped near to the project area to reduce wheelbarrowing needs.
– Use boards, forms or guides to mark layouts for accurate gravel placement.
– For driveways, request delivery trucks to back up onto the prepared subgrade for direct dumping.
– Spread dumped piles out consistently to the desired depth plus a bit extra before compacting.
– Use a tamper, roller or plate compactor to settle the gravel and lock stones together, making 2-3 passes across the whole area.
– Supplement thin spots before doing a final pass with the compactor to achieve an even thickness.
– Work the surface with a rake during compaction to distribute gravel smoothly and evenly as it settles.
Costs and Budgeting
Gravel costs range widely, from $15 per ton up to $60 or more per ton depending on stone type, size, and region. Mulch and crushed concrete tend to be cheaper, while decorative colored gravels or crushed stone can be more expensive. Get supplier quotes before ordering to budget accurately.
Here are some example gravel prices (per ton in USD):
– Pea gravel or mulch – $15 to $30 per ton
– 1/4 or 3/8 inch gravel – $30 to $45 per ton
– 1/2 to 1 inch gravel – $35 to $55 per ton
– Crushed bluestone or limestone – $45 to $75 per ton
– Colored gravels or landscaping stones – $55 to $100 per ton
Be sure to factor transportation costs if having it delivered. Delivery fees often range from $25 to $100 per truckload depending on mileage and minimum order amounts.
Ordering in larger bulk quantities can sometimes provide better pricing per ton. Gravel is priced cheaply by the cubic yard at quarries or landscape supply stores where you haul it yourself.
Overall gravel is one of the most economical and versatile landscaping materials for its durability and coverage per dollar. By estimating your area’s square footage and gravel depth required, then applying the coverage estimates per ton provided above, you can accurately plan and budget for your project’s gravel needs.
Conclusion
Knowing how much area a ton of gravel covers is extremely helpful for planning landscaping or construction projects. The key factors are stone size, thickness, compaction, and angularity which determine loose versus compacted coverage per ton. Typical coverage ranges from 30 to 150 square feet per ton depending on gravel specification, depth, and application. With the guidelines and tips provided above, you can now confidently estimate your gravel requirements and budget for any upcoming project. Proper planning of gravel quantity will ensure you don’t have too little or an excess amount left over.
