Polymeric Sand Calculator
A 10 by 10 foot patio of 4×8 pavers, with a 1/8 inch joint filled 2.375 inches deep, needs 89.50 lb of joint sand, which is 2 bags at 50 lb.
Last updated . Joint depth starts at 2.375 in, the 2⅜ in size for a 60 mm paver, because the joint is filled to about 1/8 in below the top. Weight starts at 100 lb/ft³, a planning figure near the 1,600 kg/m³ sand default (99.88 lb/ft³). The bag starts at 50 lb. None of these is a brand’s coverage. No prices.
Enter the patio, the paver face, the joint width, and the joint depth. The result is pounds and bags for the joints only.
How many pavers is the paver calculator. Sand under the pavers is the paver sand calculator. Gravel and bedding together are the patio calculator. The compacted base under both of those is the gravel under pavers guide.
Polymeric joint sand
Installers fill to about 1/8 in below the paver top, so the depth starts at the paver thickness. 2.375 in is the 2⅜ in size for a 60 mm paver. 60 mm converts to 2.36 in; this page uses 2.375 in. A zero joint has no volume.
100 lb/ft³ is a planning figure. The 1,600 kg/m³ sand default on this site is 99.88 lb/ft³. The 50 lb bag is a planning bag, not a brand yield. No price.
Results
How the joint volume is counted
Volume = patio area × (1 − face ÷ module) × joint depth. The module is (paver length + joint width) × (paver width + joint width). That puts the joint on two sides of each paver and counts the little square at the corner once. A 4 × 8 in paver with a 1/8 in joint has a module of 4.125 × 8.125 in. On 100 square feet the module count is 429.65, which is the paver count at that joint before waste.
Weight is the volume in cubic feet times 100 lb/ft³. That 100 is a rounded planning figure. The 1,600 kg/m³ sand default used elsewhere on the site is 99.88 lb/ft³. Bags divide the pounds by 50 and round up. Installers fill to about 1/8 in below the paver top, so the depth starts at 2.375 in, the 2⅜ in size for a 60 mm paver. On this patio that is 0.90 cubic feet and 89.50 lb, so the order is 2 bags. A 1 inch fill is the shallow alternate: 0.38 cubic feet and 37.68 lb, which is 1 bag.
Paver sizes on 100 square feet
Joint width is 1/8 inch. Depth is 2.375 inches except the last row. Weight is 100 lb/ft³. Bags are 50 lb, rounded up.
| Paver | Depth | Modules | Volume | Pounds | 50 lb bags |
|---|---|---|---|---|---|
| 4 × 8 in | 2.375 in | 429.65 | 0.90 ft³ | 89.50 | 2 |
| 6 × 6 in | 2.375 in | 383.84 | 0.80 ft³ | 79.96 | 2 |
| 12 × 12 in | 2.375 in | 97.95 | 0.41 ft³ | 40.60 | 1 |
| 4 × 8 in, 1 in fill | 1 in | 429.65 | 0.38 ft³ | 37.68 | 1 |
Paver thickness
The joint is filled to about 1/8 in below the top, so the depth follows the paver. 2.375 in is the 2⅜ in size for a 60 mm paver, and it is the default. 60 mm converts to 2.36 in. 3.125 in is the 3⅛ in size listed here for an 80 mm paver. 80 mm converts to 3.15 in. A thin paver is 1.5 in. These are planning thicknesses for the joint, not a brand’s paver.
| Paver | Depth to type | Volume | Pounds | 50 lb bags |
|---|---|---|---|---|
| 60 mm | 2.375 in | 0.90 ft³ | 89.50 | 2 |
| 80 mm | 3.125 in | 1.18 ft³ | 117.76 | 3 |
| Thin paver | 1.5 in | 0.57 ft³ | 56.53 | 2 |
The same 100 square feet at a 1 in fill, the shallow alternate, is 0.38 ft³ and 37.68 lb, which is 1 bag.
Worked example
Leave every field as it opens: patio 10 ft by 10 ft, face 4 × 8 in, joint width 0.125 in, joint depth 2.375 in, weight 100 lb/ft³, bag 50 lb. Area reads 100.00 ft² · 9.29 m². Modules read 429.65. Joint share reads 4.52%. Volume reads 0.90 ft³ · 0.03 m³. Weight reads 89.50 lb. Bags read 2.
Frequently asked questions
How much polymeric sand do I need?
Leave the patio at 10 ft by 10 ft, the paver at 4 × 8 in, the joint at 0.125 in wide and 2.375 in deep, the weight at 100 lb/ft³, and the bag at 50 lb. Area reads 100.00 ft² · 9.29 m². Modules read 429.65. Joint share reads 4.52%. Volume reads 0.90 ft³ · 0.03 m³. Weight reads 89.50 lb. Bags read 2.
What is the joint volume formula?
Volume = patio area × (1 − face ÷ module) × joint depth. The module is (paver length + joint) × (paver width + joint). For 4 in and 8 in with a 1/8 in joint, the module is 4.125 × 8.125 in. The joint on two sides of each paver includes the corner once, so the corner is not counted twice. On 100 square feet that is 429.65 modules, the same count as the paver calculator at a 1/8 in joint before waste.
How many 50 lb bags is 89.50 pounds?
89.50 ÷ 50 is 1.79, which rounds up to 2 bags. The bag weight starts at 50 lb as a planning bag, not a brand’s coverage. A zero joint has no volume and the bag line reads 0. This page does not add a waste percent on top of the joint.
How much sand do other paver sizes need?
On the same 100 square feet, a 1/8 in joint, and the 2.375 in depth: 6 × 6 is 383.84 modules, 0.80 ft³, and 79.96 lb, still 2 bags. 12 × 12 is 97.95 modules, 0.41 ft³, and 40.60 lb, which is 1 bag. The pounds change with the face.
Why is the joint depth 2.375 inches?
Installers fill to about 1/8 in below the paver top, so the joint depth is the paver thickness. The default is 2.375 in, the 2⅜ in size for a 60 mm paver (60 mm converts to 2.36 in), and the result is 0.90 ft³ · 0.03 m³, 89.50 lb, and 2 bags. Set the depth to 3.125 for the 3⅛ in size listed with an 80 mm paver and the same patio reads 1.18 ft³ · 0.03 m³, 117.76 lb, 3 bags. A 1.5 in thin paver reads 0.57 ft³ · 0.02 m³, 56.53 lb, 2 bags, and a 1 in fill is the shallow alternate at 0.38 ft³ · 0.01 m³, 37.68 lb, 1 bag.
How much sand for a 20 by 20 patio?
Set both sides to 20 ft and leave the depth at 2.375 in. Area reads 400.00 ft² · 37.16 m². Modules read 1,718.60. Volume reads 3.58 ft³ · 0.10 m³. Weight reads 358.00 lb. Bags read 8. It is four times the 10 by 10, because the joint share does not change.
Is this the sand under the pavers?
No. This is the sand in the joints after the pavers are laid. Bedding sand under the pavers is the paver sand calculator, and a 1 inch bed over this 100 square feet is a bulk volume, not 89.50 lb of joint sand. The 100 lb/ft³ used here is a planning weight. The site’s 1,600 kg/m³ sand default is 99.88 lb/ft³. No price is shown.