Pick the right sand first
"Sand" covers several products, and using the wrong one is a common mistake:
- Concrete sand (coarse, washed) is the bedding layer under pavers. ICPI's construction guide specifies bedding sand meeting the ASTM C33 concrete sand gradation.
- Mason sand is finer, for mortar and some joint filling.
- Play sand is washed, fine and soft. Use it for sandboxes, not under pavers.
- Polymeric jointing sand is swept into paver joints after laying. Coverage depends on the joint width and paver size, so use the bag's coverage chart.
- Fill sand is a general backfill whose quality varies by supplier.
Volume and weight
Volume = length × width × (depth ÷ 12) plus waste. Weight = cubic yards × density. Published reference ranges put dry sand at roughly 1.3–1.5 tons per cubic yard and wet sand at 1.5–1.7. The default is 1.35. Bags are figured by volume, so a 50 lb bag of dry sand is about 0.5 ft³ (approximate, based on roughly 100 lb per ft³).
With the defaults (12 × 10 ft at 1 in, 10% waste): 0.41 yd³ (11 ft³), 0.55 tons or 22 50 lb bags.
Sand under pavers
ICPI Tech Spec 2 calls for bedding sand screeded to an uncompacted nominal 1 in over the compacted base. It also warns not to use the sand to make up for an uneven base, because the unevenness will show through on the surface over time. So the bedding volume is simply patio area × 1 in. That's 1 ft³ for every 12 ft².
| Patio size | Bedding sand at 1 in (+10%) | 50 lb bags |
|---|---|---|
| 10 × 10 ft | 0.34 yd³ (9.2 ft³) | 19 |
| 12 × 12 ft | 0.49 yd³ (13.2 ft³) | 27 |
| 12 × 16 ft | 0.65 yd³ (17.6 ft³) | 36 |
| 16 × 20 ft | 1.09 yd³ (29.3 ft³) | 59 |
| 20 × 20 ft | 1.36 yd³ (36.7 ft³) | 74 |
| Patio size | Bedding sand at 2.5 cm (+10%) | 25 kg bags |
|---|---|---|
| 3 × 3 m | 0.248 m³ (248 L) | 16 |
| 3.6 × 3.6 m | 0.356 m³ (356 L) | 23 |
| 3.6 × 4.8 m | 0.475 m³ (475 L) | 31 |
| 4.8 × 6 m | 0.792 m³ (792 L) | 51 |
| 6 × 6 m | 0.99 m³ (990 L) | 64 |
The paver calculator gives you pavers, base gravel and bedding sand together.
Sandboxes
Fill a sandbox about two-thirds to three-quarters of its height so sand stays in when kids dig (a practical rule of thumb). A 5 × 5 ft box with 12 in sides filled 9 in deep needs 0.69 yd³ (18.8 ft³), or 38 50 lb bags of play sand. A breathable cover keeps out animals and rain.
Worked examples
Bedding for a 16 × 20 ft patioBedding for a 4.88 × 6.1 m patio
Length 20 ft · Width 16 ft · Depth 1 in · Sand density 1.35 tons/yd³ · Waste / overage 10 % · Bag weight 50 lbLength 6.1 m · Width 4.88 m · Depth 2.5 cm · Sand density 1.6 t/m³ · Waste / overage 10 % · Bag weight 22.7 kg
- Volume: 1.09 yd³ (29.3 ft³)Volume: 0.831 m³ (831 L)
- Weight: 1.47 tonsWeight: 1.33 tonnes
- Bags (50 lb each): 59Bags (22.7 kg each): 59
Pool base, 18 ft round (enter area 254 ft²) at 2 inPool base, 5.49 m round (enter area 23.6 m²) at 5.1 cm
Length 254 ft · Width 1 ft · Depth 2 in · Sand density 1.35 tons/yd³ · Waste / overage 10 % · Bag weight 50 lbLength 77.42 m · Width 0.3 m · Depth 5.1 cm · Sand density 1.6 t/m³ · Waste / overage 10 % · Bag weight 22.7 kg
- Volume: 1.72 yd³ (46.6 ft³)Volume: 1.32 m³
- Weight: 2.33 tonsWeight: 2.11 tonnes
Check the pool maker's instructions. Many specify the base material and depth.
Tips
- Keep bedding sand dry and loose until you screed it. ICPI says not to install saturated or frozen sand.
- Buy bulk sand by the ton or yard for anything over about ½ yd³. Bags add up quickly.
- Cutting pavers or stone creates silica dust. Cut wet and follow OSHA's silica guidance.
Jointing sand for pavers
After the pavers are laid and compacted, sand is swept into the joints to lock them together. Joint sand coverage depends on the paver size, its thickness and the joint width. Small pavers with lots of joints use far more sand per square foot than large slabs. That's why polymeric sand bags quote a coverage range, sometimes by paver type. Buy by the manufacturer's chart and keep a spare bag. Polymeric sand has to be completely dry when installed, and it must be activated with water exactly as the bag directs, or it can haze the pavers or fail to harden.
Common mistakes
- Leveling a bad base with sand. ICPI is explicit: fix the base, then screed a uniform 1 in bed.
- Compacting bedding sand before laying pavers. It's screeded loose and gets compacted through the pavers.
- Mixing up tons and yards. Sand sold by the ton is about 0.67–0.77 yd³ per ton at 1.3–1.5 t/yd³.
- Leaving the pile uncovered. Wet sand is heavier, harder to screed and messy to haul.
Screeding bedding sand
Bedding sand sits on top of the compacted base as a smooth, uncompacted layer about 1 in thick (ICPI). A common way to get an even layer:
- Lay two 1 in outside-diameter pipes or screed rails on the base, a few feet apart.
- Spread sand over them and pull a straight board across the rails to strike it off.
- Lift out the rails and fill the grooves with sand, smoothing them with a trowel.
- Don't walk on the screeded sand. Lay pavers from the finished side, then compact the pavers to set them into the sand.
Don't use the sand to fill dips in the base. ICPI says to correct the base itself, since thick spots in the sand settle unevenly.
Checked against
Each case below is re-run against the calculator by our automated test suite.
| Case | Our result | Checked against | Result |
|---|---|---|---|
| 12 × 10 ft, 1 in deep, no waste: volume | 0.37 yd³ (10 ft³) | Hand calculation | Match |
| Case | Our result | Checked against | Result |
|---|---|---|---|
| 3.66 × 3.05 m, 2.5 cm deep, no waste: volume | 0.283 m³ (283 L) | Hand calculation | Match |
Frequently asked questions
How much sand do I need under pavers?
About 1 in of uncompacted bedding sand (ICPI). That's 1 ft³ per 12 ft² of patio.
How much does a yard of sand weigh?
Roughly 1.3–1.5 tons dry and 1.5–1.7 tons wet (published reference ranges).
How many 50 lb bags of sand in a yard?
Around 54, assuming about 0.5 ft³ per bag (approximate). The exact number depends on the sand.
Can I use play sand under pavers?
It isn't recommended. ICPI specifies coarse concrete sand (ASTM C33) for bedding.
Sources & assumptions
The results are planning estimates, and the cost figures only use prices you enter. Product yields, densities and coverage rates vary, so check the label or ask your supplier, and follow local codes. Figures marked "approximate" or "rule of thumb" are general practice, not exact standards.
- ICPI Tech Spec 2: Construction of Interlocking Concrete Pavements
- Inch Calculator: weight per cubic yard of landscape materials (published reference ranges)
- OSHA fact sheet: Controlling silica dust from handheld power saws
See how we calculate and test our formulas and the changelog. Last updated 2026-10-08.
Reviewed by the MaterialWhiz Editorial Team. This estimate uses the assumptions shown in the calculator. Review the result against your supplier's product coverage and site conditions. Last reviewed: October 10, 2026. See how we calculate · Report a correction.