Paver Patio: How Much Base, Sand and Pavers You Need and How to Build It

How much base, sand and pavers do you need for a paver patio?

Work out the area first, then convert to three materials: compacted base stone, bedding sand and pavers. The Interlocking Concrete Pavement Institute (ICPI, now part of the Concrete Masonry and Hardscapes Association) says minimum aggregate base thickness for walks should be 4 to 6 in., with 6 to 8 in. under driveways, and bedding sand is placed 1 in. thick (screeded 1 to 1 1/2 in. uncompacted). Your pavers sit on top, and a pedestrian paver is typically at least 2 3/8 in. thick.

Worked example, a 12 ft by 16 ft patio: 12 x 16 = 192 sq ft. Excavation depth is base + sand + paver thickness, so 4 in. + 1 in. + 2.375 in. = about 7.4 in. for a 4 in. base, or 9.4 in. for a 6 in. base. That is 192 x 7.375 / 12 = 118 cu ft (4.4 cu yd) to 192 x 9.375 / 12 = 150 cu ft (5.6 cu yd) of soil to remove, before you add the extra width needed around the edges for the restraint.

Base stone: 192 sq ft x 4 in. / 12 = 64 cu ft (2.4 cu yd) or, at 6 in., 96 cu ft (3.6 cu yd). Crushed stone weighs about 1.4 tons per cubic yard, so that is about 3.3 to 5.0 tons. Add 10 percent for waste and settling, a figure highway agencies use for aggregate, and you order about 3.7 to 5.5 tons. Bedding sand: 192 x 1 in. / 12 = 16 cu ft (0.6 cu yd), up to 24 cu ft (0.9 cu yd) if screeded at 1 1/2 in.

Pavers per square foot depends on the unit. A 4 x 8 in. paver (actual 7.875 x 3.875 in.) runs about 4.58 pieces per square foot according to a manufacturer sheet that lists 540 units covering 117.9 sq ft. A 6 x 9 in. paver covers 54 sq in., or 0.375 sq ft, so it takes about 2.67 per square foot (our arithmetic from the nominal size). For 192 sq ft that is about 880 four-by-eights or 513 six-by-nines before waste. One paver manufacturer advises adding 10 percent for straight-lay patterns and 15 to 20 percent for diagonal, herringbone or curved layouts. At 10 percent you order about 968 four-by-eights or 565 six-by-nines; at 15 percent, about 1,012 or 590.

Choosing the right pavers and joint type

For foot traffic and patio furniture, the ICPI recommends pavers 2 3/8 in. (60 mm) thick, the same minimum thickness defined by the ASTM C936 standard that US-made concrete pavers typically meet. Thicker units, 3 1/8 in. (80 mm), are for vehicles.

Running bond and stack bond need few cuts. Herringbone interlocks best, but on a patio it mainly means more diagonal cuts and a higher waste percentage.

Joint filler is a second choice. ICPI says plain dry joint sand meeting ASTM C144 (often called mason sand) is the standard material, and bedding sand can also be used. Polymeric sand, a sand and binder blend that hardens after wetting, is optional. ICPI's tech note says joint sand stabilization is generally not required for many pavements, because sand in joints stabilizes on its own over time.

What to buy: categories and a checklist

Buy by specification and ask each supplier to confirm it.

• Concrete pavers at least 2 3/8 in. thick from one production run, with spacer bars on the sides.
• Aggregate base: crushed stone graded for road base under asphalt. ICPI says base material should conform to what is used under asphalt, or ASTM D2940 where no local standard exists.
• Bedding sand: coarse, washed concrete sand meeting ASTM C33. ICPI says do not use mason sand for bedding, and do not use stone dust or screenings.
• Edge restraints designed for pavers (plastic, aluminum, steel or a concrete collar) with the right spikes for the type. Timber is not recommended.
• Joint sand (ASTM C144) or polymeric sand, counted from the coverage rating on the bag.
• A plate compactor rated for at least 5,000 lbf of centrifugal force, a protective pad for the plate, and a hand tamper for tight spots.
• A wet-cutting masonry saw or a splitter, a long straightedge, string line, stakes, screed rails, a level, a stiff broom and a leaf blower.
• Gloves, eye and hearing protection, a respirator and sturdy boots.

Preparing the site

Call your local utility locating service before you dig. The industry guide says to call at least two days before excavation so utility lines are marked. Then lay out the patio with stakes set a short distance outside the dig, so they survive excavation, and run string lines at the finished height and slope.

Remove sod, roots and organic soil. The tech note says organic material, debris and large rocks should be removed and replaced with clean, compacted aggregate, and standing water should be removed from the soil.

Excavate to the depths calculated above, and wider than the planned paver edge to leave room for the edge restraint and the base beyond its spikes.

Base compaction and slope for drainage

Compact the bare soil first. ICPI specifies at least 98 percent of standard Proctor density (ASTM D698) for the soil subgrade under pedestrian areas and residential driveways. Measuring that takes a testing service, so a homeowner's practical goal is firm ground that does not move under the compactor. The ideal soil moisture is damp but not wet: it should stick together as a ball when squeezed and break into a few pieces when dropped from 6 to 12 in.

Spread the base stone in lifts. The industry note says to compact base in 4 to 6 in. lifts with 7,000 lbf reversible plate compactors, and that thinner lifts are required for compactors in the 5,000 lbf range. With a typical 5,000 lbf machine, build a 6 in. base in two lifts. Compact the base to at least 98 percent of standard Proctor density. The finished base should be smooth to within plus or minus 3/8 in. over a 10 ft straightedge.

Build the slope into the base, not the sand. The CMHA tech note says slopes should be a minimum of 1.5 percent, about 3/16 in. per foot, so water runs off the surface. Slope away from the house and any foundation wall. Check your local code, which may require more near buildings.

Edge restraints are not optional

ICPI calls edge restraints essential to performance. Without them the pavers spread under foot traffic, joints open, and the interlock that holds the surface together is lost. Walks and patios can use steel, aluminum, concrete or plastic edging made for pavers, and a building wall also works. Soil backfill never does.

Set restraints at the correct height before the sand goes down. In ICPI's example, pavers 2 3/8 in. thick on 1 in. of bedding sand put the base 3 in. below the finished paver surface, which allows for settlement.

Spiked edging needs base extending past the spikes. The rule of thumb is by at least the thickness of the base, and for residential projects the distance from the stakes to the edge of the base should be consistent and not more than 10 in.

Step by step: building the patio

• 1. Call for utility locates, mark the area, and stake string lines at finished height with a slope of at least 1.5 percent.
• 2. Excavate to base depth + 1 in. of sand + paver thickness, wider than the patio on every edge for the restraint.
• 3. Remove organic soil and soft spots, then compact the subgrade until firm.
• 4. Add base stone in lifts your compactor can handle, compact each lift, and check slope and flatness with string and a straightedge.
• 5. Install edge restraints on the compacted base and spike them according to the manufacturer.
• 6. Lay screed rails or pipes and spread bedding sand to a uniform 1 in. (up to 1 1/2 in. uncompacted). Screed it smooth and do not walk on it.
• 7. Place pavers from a corner, drawing from several bundles to blend color, with joints of 1/16 to 3/16 in. Use string lines for straight joints and kneel on a board.
• 8. Cut edge pavers to fit. Fill any gap wider than 3/8 in. with a cut paver.
• 9. Compact the pavers with the plate compactor, making at least two passes, with a pad on the plate. Stay 6 ft from any unrestrained edge until it is closed.
• 10. Sweep dry joint sand into the joints, compact again, and repeat until the joints are full. Sweep off the excess.

Joint sand, polymeric sand, sealing and drying times

Standard joint sand needs no cure. Set the finished surface 1/8 to 1/4 in. above adjacent edges to allow for settling, and keep lippage between pavers under 1/8 in.

Polymeric sand adds steps. The manufacturer's data sheet requires mechanical compaction first, joints at least 1.5 in. deep, a dry surface and no rain forecast for 24 hours, with temperatures above 32 F for 48 hours. Sweep it in, compact, refill, clear every grain from the paver faces, and leave the sand at least 1/8 in. below the paver top. Shower for about 30 seconds, wait, and repeat until water no longer penetrates; over-watering lengthens cure time. The sheet says foot traffic is allowed immediately, vehicle traffic after 48 to 72 hours, and the sand can handle unexpected rain after 60 minutes, though 24 hours without rain is recommended.

Coverage for one 50 lb bag is stated as 60 to 120 sq ft for narrow joints and 25 to 40 sq ft for wide joints. For our 192 sq ft patio with narrow joints, that is 192 / 120 = 1.6 to 192 / 60 = 3.2, so buy 2 to 4 bags.

Sealing is optional. The CMHA tech note says sealers do not add structural strength; they deepen color, resist stains and can stabilize joint sand. Allow 24 hours of dry surface before sealing, and use a sealer made for concrete pavers. The polymeric sand data sheet says to wait for the joints to harden before cleaning or sealing, typically about 30 days. Efflorescence, a whitish powder that does not affect structural performance, may peak about 60 days after installation, so many installers wait before sealing.

Common mistakes

• Skipping the edge restraint, or setting it on soil with no base behind the spikes.
• Using stone dust, screenings or mason sand for bedding, which drain poorly and compact unevenly.
• Trying to fix a low spot in the base by adding extra bedding sand.
• Compacting a thick base in one lift.
• Building a flat patio with no slope, or sloping toward the house.
• Working with polymeric sand on a damp surface, over-watering it, or leaving sand dust on the paver faces where it hardens into a haze.
• Ordering no allowance for cuts, then finding the color lot has changed.
• Compacting right up to an unrestrained edge, which pushes pavers out.

Safety and when to hire a professional

Cutting pavers makes silica dust. OSHA says using a stationary masonry saw to cut pavers and other silica-containing materials can generate respirable crystalline silica dust that, inhaled over time, can irreversibly damage the lungs. OSHA identifies wet cutting, with a water delivery system that continuously feeds the blade, as an effective control, and notes that wet cutting indoors or in enclosed areas may not reliably keep exposure low. Cut outdoors, with water running, and wear a respirator for dry work. Use GFCI protection with electric tools around water.

Plate compactors are heavy, so wear ear protection and keep your feet clear.

Consider a professional for a large area, drainage problems near a foundation, steep slopes or retaining walls, soft or wet soil, vehicle loads, or anything needing a permit. ICPI says installation should be performed by experienced contractors who hold current certification from its Concrete Paver Installer Certification Program, and an installer with an Advanced Residential Paver Technician designation has shown knowledge of best practices. A small, level, well-drained patio is within reach for a careful DIYer, but the digging and compaction are physically demanding.

Cost and ordering tips

Pavers are sold on pallets or in bundles, and the supplier's coverage per pallet is the number to use. Ask for the actual unit size and the number of pieces per square foot, because nominal sizes differ from actual sizes (a 4 x 8 paver is often 3.875 x 7.875 in.). Order enough from the same production run, plus the waste allowance, and keep a few spares for future repairs.

Bulk stone and sand need delivery access and a place to put them; bags suit small patios or tight access. Ask the supplier about the grading of each product, whether the sand meets ASTM C33, and whether the base stone is the type used under asphalt. For bulk orders, ask how tons convert to cubic yards and how they will place the load.

Care and maintenance

Sweep regularly and refill joints when sand washes out. Standard joint sand may need topping up as it settles. Use cleaners made for concrete pavers and test them on a small area first. A low-angle, wide-nozzle spray is less likely to dislodge joint sand. The polymeric sand data sheet restricts power washing for the first 30 days.

If a section sinks, lift the pavers, correct the base underneath, re-screed the sand and relay them. Moss grows where joints stay damp, shaded or full of organic debris.

How much for common patio sizes

Each row uses 4 x 8 in pavers (about 4.58 per sq ft), a simple layout with 10% extra, a 4 in compacted base with 25% extra for compaction, and 1 in of bedding sand. Change any number in the paver patio calculator.

Frequently asked questions

Sources: ICPI Tech Spec 10, Application Guide for Interlocking Concrete Pavements (CMHA, 2022), CMHA Tech Note PAV-TEC-002-22, Construction of Interlocking Concrete Pavements, CMHA Tech Note PAV-TEC-003-22, Edge Restraints for Interlocking Concrete Pavements, CMHA Tech Note PAV-TEC-005-22, Cleaning, Sealing and Joint Sand Stabilization, Polymeric sand technical data sheet (manufacturer), coverage, joints, compaction and drying, Unilock Hollandstone 4x8 product sheet, Western Interlock, how to calculate paver stones needed, OSHA Fact Sheet: Control of Silica Dust in Construction, Stationary Masonry Saws. Read 7 November 2026.