Paver installation has two sand-related decisions that most people only think about as one: the crushed stone base layer, and the sand bedding layer. Each serves a completely different purpose, and sizing them correctly is what keeps a patio or walkway from shifting and settling years after installation.
Here is exactly how to calculate both.
The two layers you need
Layer 1: Crushed stone base. This is the structural layer. It distributes the weight of the pavers and traffic, provides drainage, and prevents frost heave. This is almost always crushed gravel or crushed stone, not sand.
Layer 2: Bedding sand. This goes on top of the compacted base. It is 1 inch thick and gives you the ability to fine-tune the level of each paver during installation. Polymeric sand fills the joints between pavers after installation, which is a third material entirely.
Most people think they just need “sand for pavers.” They actually need gravel for the base, sand for the bed, and polymeric sand for the joints. These are three separate orders.
How to size the crushed stone base
Base depth depends on how the surface will be used.
Foot traffic only (patios, walkways): 4 inches of compacted crushed stone is sufficient in most regions.
Vehicle traffic (driveways, parking pads): 6 to 8 inches of compacted crushed stone. Less than 6 inches and vehicle weight will eventually cause settling.
Cold climates with deep frost: Add 2 inches to whichever depth applies to your use case.
To calculate cubic yards of base material:
Cubic yards = (length ft x width ft x depth in) / 324
For a 12 by 16 foot patio with a 4-inch base:
- (12 x 16 x 4) / 324 = 768 / 324 = 2.4 cubic yards
- Add 10 percent for compaction: 2.4 x 1.10 = 2.6 cubic yards
Crushed stone compacts about 10 to 15 percent under a plate compactor, so you need more loose material than the final compacted depth.
How to size the bedding sand
The bedding sand is always 1 inch deep. This is the standard across all paver manufacturers. Do not go thicker: a bedding sand layer deeper than 1 inch is unstable and will cause pavers to rock.
To calculate cubic yards of bedding sand:
Cubic yards = (length ft x width ft x 1 in) / 324
For the same 12 by 16 foot patio:
- (12 x 16 x 1) / 324 = 192 / 324 = 0.59 cubic yards
In this case, you need just over half a cubic yard of bedding sand. Most sand suppliers have a half-yard minimum for delivery, so you would order 1 cubic yard.
Polymeric sand for joints
After pavers are set and leveled, the joints between them get filled with polymeric sand. This is a different product from bedding sand: it contains binders that harden when wet, locking the pavers in place and blocking weeds.
Coverage for joint sand depends on paver size and joint width. Narrow joints (1/4 inch) on large pavers use less. Wide joints (1 inch) on small pavers use significantly more. As a rough guide:
| Paver size | Typical joint sand coverage per 50 lb bag |
|---|---|
| 4 x 8 inch | 25 to 35 sq ft |
| 6 x 6 inch | 40 to 55 sq ft |
| 12 x 12 inch | 80 to 100 sq ft |
| 12 x 24 inch | 100 to 130 sq ft |
These are estimates. The coverage rate on the bag is more accurate for your specific product.
A complete material list for a 12 x 16 patio
| Material | Amount |
|---|---|
| Crushed stone base (4 in) | 2.6 cubic yards |
| Bedding sand (1 in) | 0.6 cubic yards (order 1 yd) |
| Polymeric joint sand (for 6x6 pavers at 1/4 in joint) | 6 to 7 bags |
| Pavers | Patio area + 10 percent waste |
The most common paver installation mistake
Skipping or thinning the base to save money. A thin base settles unevenly, and once pavers shift, releveling requires pulling them up and starting the base over. The extra cost of a proper 4-inch compacted base is trivial compared to rebuilding the project in 3 years.
Use the paver sand calculator to get exact quantities for your project dimensions, including both the base and bedding layers. For any additional sand needs around the project, the sand calculator handles bulk quantities in cubic yards or tons.