How to Estimate Pavers, Base, and Sand for a Patio
Estimating a paver job comes down to three layers stacked on a number you can't fudge: square footage. Get the area right, apply the correct depths and waste, and the pavers, base, and sand fall out cleanly. Here is the method estimators actually use in the field.
Start With Square Footage, Not Paver Count
Every layer keys off net area. For a rectangle, length times width in feet gives square footage. Break irregular shapes into rectangles, triangles, and circles, calculate each, and add them up. A triangle is one-half base times height; a circle is 3.14 times the radius squared.
Always sketch and measure the actual ground, not the plan dimensions. Curves, step-downs, and out-of-square corners are where takeoffs go wrong. Measure twice, and record both the gross area and any cutouts (planters, posts, existing slab) you'll subtract.
Do not estimate by counting individual pavers off a pattern. Buy pavers by coverage, which is sold per square foot or per layer/bundle, and let the supplier convert square footage into bundles for the specific unit you spec.
Pavers: Coverage Plus a Waste Factor
Once you have net square footage, add waste before ordering. Use roughly 5 percent for a simple rectangular field with straight 90-degree borders, 10 percent for standard layouts with some cuts, and 10 to 15 percent for diagonal/herringbone patterns, curves, or circle kits where every perimeter piece gets cut. Breakage and color-blending also eat into yield.
Order full bundles, and order all of it in one delivery so the dye lot matches. Pavers from different production runs can shade differently, and a mid-job reorder is the classic way to end up with a visible stripe across a patio.
Keep a few square feet of leftovers on site for the owner. Future repairs almost never match a fresh dye lot, so the extra bundle is cheap insurance, not waste.
Base Gravel: Depth Drives Everything
Crushed aggregate base (often called road base, crusher run, or 3/4-inch minus) is your structural layer. A common rule of thumb is 4 to 6 inches of compacted base for pedestrian patios and walkways, and 8 to 12 inches for driveways or anything carrying vehicle loads. Increase depth in clay or poorly draining soils and in freeze-thaw climates.
Convert depth to volume in cubic yards: square feet times depth in feet, divided by 27. For 300 square feet at 6 inches, that is 300 times 0.5 divided by 27, which is about 5.6 cubic yards before compaction. Aggregate compacts roughly 20 to 25 percent, so order about 15 to 20 percent extra loose material to finish at the target depth, and compact in 2-to-3-inch lifts.
Aggregate is also sold by the ton. As a working figure, crushed stone runs around 1.4 to 1.5 tons per cubic yard, so multiply your yardage by about 1.4 if the quarry quotes by weight. Confirm the supplier's actual conversion for their material.
Bedding Sand and Joint Sand Are Two Separate Buys
The setting bed is a screeded layer of coarse, sharp concrete sand, typically 1 inch thick (1.5 inches max). Never exceed that or the pavers will rut. One inch over an area: square feet times 1/12, divided by 27 for cubic yards. For 300 square feet that is about 0.93 cubic yard. Sand runs roughly 1.3 to 1.4 tons per cubic yard if bought by weight. Do not use the setting bed to correct grade; that is the base's job.
Joint sand is a separate line item. Polymeric sand for filling joints is sold by the bag, and coverage depends heavily on joint width and paver thickness. A bag commonly covers somewhere in the range of about 30 to 90 square feet for standard pavers, much less for wide or thick-paver joints, so always read the specific product's coverage chart and round up.
Hold back a small amount of bedding sand for screeding touch-ups, and budget extra joint sand for a second pass after the first watering settles it.
Edge Restraint, Geotextile, and Steps
Estimate edge restraint by linear foot of open perimeter, plus spikes (often around one per foot to roughly every 12 inches). A geotextile separation fabric between subgrade and base is cheap insurance over soft or clay soils; estimate it by square footage plus overlap at seams.
For steps, plan the geometry before ordering. A comfortable, code-typical exterior stair uses risers around 7 inches and treads/run around 11 inches or more, with all risers in a flight kept uniform (variation between the largest and smallest riser held to about 3/8 inch under common code). Confirm your local code before committing dimensions.
A LiDAR scan with ProBuildCalc turns the as-built patio footprint into a measured area and perimeter, so your paver, base, sand, and edge-restraint quantities come off real dimensions instead of a pacing guess.
A Quick Worked Example
Say a 12-by-25-foot patio: 300 square feet net. Pavers in a running-bond pattern with cut borders: add 10 percent, so order coverage for about 330 square feet in one dye lot.
Base at 6 inches compacted: about 5.6 cubic yards in place, order roughly 6.5 to 7 yards loose (or about 9 to 10 tons) to allow for compaction. Bedding sand at 1 inch: about 1 cubic yard. Joint sand: figure square footage against the chosen product's coverage chart and round up to whole bags.
Add perimeter edge restraint by the linear foot plus spikes, and geotextile fabric if the soil is soft. Label every quantity by layer on the takeoff so the field crew and the supplier read the same numbers.
Related free calculators
Stop estimating by hand
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FAQ
- How much waste should I add to a paver order?
- Roughly 5 percent for a simple rectangle with straight borders, about 10 percent for standard layouts with some cutting, and 10 to 15 percent for herringbone, diagonal, or curved layouts where most perimeter pieces get cut. Order all pavers in one dye lot and keep a few square feet for future repairs.
- How deep should the gravel base be under pavers?
- A common rule of thumb is 4 to 6 inches of compacted crushed base for pedestrian patios and walkways, and 8 to 12 inches for driveways or vehicle loads. Go deeper in clay, poor-draining soil, or freeze-thaw climates, and compact in 2-to-3-inch lifts.
- How thick should the bedding sand layer be?
- Screed coarse concrete sand to about 1 inch, with 1.5 inches as a practical maximum. A thicker bed lets pavers settle and rut. The setting bed is for bedding only, not for fixing grade, which is the base layer's job.
- How do I convert depth into cubic yards of material?
- Multiply square footage by the depth in feet, then divide by 27. For example, 300 square feet at 6 inches is 300 times 0.5 divided by 27, about 5.6 cubic yards. Then add 15 to 20 percent extra for base gravel to account for compaction.