How much crushed concrete do I need per square foot?

At 4 inches deep, you need approximately 0.012 tons (24 lbs) per square foot of crushed concrete, or about 1 ton per 50–60 square feet. At 6 inches deep, plan for 1 ton per 33–40 square feet.

How much does crushed concrete cost per ton?

Crushed concrete (recycled concrete aggregate) costs $10–$25 per ton in 2026, significantly cheaper than new crushed limestone ($25–$50/ton) or pea gravel ($30–$55/ton). Delivery fees add $75–$150 per truckload.

Can I use crushed concrete as a base under a new concrete slab?

Yes. A 4–6 inch layer of compacted crushed concrete makes an excellent base under new slabs. Use ¾-inch minus grade, compact in 3-inch lifts with a plate compactor, and allow 24 hours settling time before pouring.

What is the difference between crushed concrete and gravel?

Crushed concrete is recycled from old concrete structures, making it cheaper ($10–$25/ton vs $25–$60/ton for virgin stone). It compacts better due to angular particles and cement residue, but has a high pH (11–12) that can harm acid-loving plants.

Crushed Concrete Calculator: How Much Base Material Do You Need?

Quick formula: Tons needed = Length (ft) × Width (ft) × Depth (in) ÷ 12 ÷ 27 × 1.35. At 4 inches deep, 1 ton covers 50–60 sq ft. Crushed concrete costs $10–$25 per ton — roughly half the price of new crushed stone.

What Is Crushed Concrete?

Crushed concrete (also called recycled concrete aggregate or RCA) is old concrete that’s been processed through a crusher into gravel-sized pieces. It costs $10–$25 per ton (significantly cheaper than virgin stone at $25–$60/ton) and is widely used as a base material under new slabs, as driveway surfacing, and as fill material.

Crushed Concrete Calculator Formula

Calculating how much crushed concrete you need uses the same volume formula as any fill material:

Tons needed = (Length × Width × Depth in feet) ÷ 27 × 1.35

The 1.35 factor converts cubic yards to tons, since crushed concrete weighs approximately 2,700 lbs (1.35 tons) per cubic yard when compacted.

Step-by-Step Calculation

Measure your area in feet (length × width)
Decide your depth (typically 4–6 inches for base, 2–3 inches for top dressing)
Calculate cubic feet: L × W × (depth in inches ÷ 12)
Convert to cubic yards: divide by 27
Convert to tons: multiply by 1.35
Add 10% for compaction and waste

Example: Driveway Base Layer

For a 12×40 foot driveway at 6 inches of crushed concrete:

Volume = 12 × 40 × (6÷12) = 240 cu ft
Cubic yards = 240 ÷ 27 = 8.89 yd³
Tons = 8.89 × 1.35 = 12.0 tons
With 10% extra = 13.2 tons

Coverage Rates: Crushed Concrete

Depth	Coverage per Ton	Coverage per Cubic Yard
2 inches	100–120 sq ft	135–162 sq ft
3 inches	65–80 sq ft	90–108 sq ft
4 inches	50–60 sq ft	67–81 sq ft
6 inches	33–40 sq ft	45–54 sq ft
12 inches	17–20 sq ft	22–27 sq ft

Coverage varies based on particle size and compaction rate.

Common Uses for Crushed Concrete

As a Base Layer (Under New Concrete)

The most common use. A 4–6 inch layer of compacted crushed concrete provides excellent drainage and a stable base under new concrete slabs. It’s often cheaper than crushed limestone or gravel.

Driveway Surfacing

Crushed concrete makes an affordable driveway surface at 4–6 inches thick. It compacts well, drains water, and is significantly cheaper than poured concrete or asphalt. Best for rural properties and long driveways.

Fill Material

For filling low areas, old foundations, or raising grade. Use larger pieces (1½”–3”) for deep fills, then top with finer crushed concrete (¾” minus) for a smooth surface.

French Drain Backfill

The angular particles and good drainage properties make crushed concrete suitable for surrounding French drain pipes, though washed gravel is still preferred for the pipe zone.

Crushed Concrete vs. Gravel vs. New Stone

Material	Cost per Ton	Cost per Yard	Best For
Crushed concrete (RCA)	$10–$25	$15–$35	Base layers, fill, driveways
Crushed limestone	$25–$50	$35–$70	Base layers, drainage
Pea gravel	$30–$55	$40–$75	Drainage, landscaping
¾” clean stone	$35–$60	$50–$80	Drainage, French drains
Decomposed granite	$40–$65	$55–$90	Pathways, patios

Prices vary significantly by region and distance from the quarry/recycling facility.

Crushed Concrete Sizes Explained

Size	Particle Range	Use
Minus 3/4”	Dust to ¾”	Top dressing, compactable base
3/4” clean	¾” uniform	Drainage, pipe bedding
1½” minus	Dust to 1½”	Driveway base, fill
2”–3” rip-rap	2”–3” chunks	Deep fill, erosion control
3/8” minus	Dust to 3/8”	Fine top coat, paver base

For base layers under concrete, use ¾” minus — it has a mix of fine and coarse particles that compact together into a solid base.

Tips for Using Crushed Concrete

Compact in lifts — Don’t dump 6 inches and compact once. Place 3-inch lifts and compact each separately with a plate compactor.
Wet before compacting — Moisture helps the fines bind together. Spray lightly between lifts.
Check pH — Crushed concrete is alkalite (pH 11–12). Don’t use it near acid-loving plants or where water will run into garden beds.
Source matters — Ask your supplier what the source material was. Reinforced concrete rubble is fine; material from contaminated sites is not.
Allow settling time — If using as a base under new concrete, let compacted crushed concrete settle for at least 24 hours (longer is better) before pouring.

Calculate Your Project

While our main calculator at freeconcretecalc.com is designed for poured concrete projects, you can use the slab calculator to figure out the cubic footage for a crushed concrete base layer. Enter the area dimensions and depth, then convert the cubic feet result to tons by dividing by 20 (approximate: 1 ton covers 20 cu ft of crushed concrete at loose fill).

For calculating the poured concrete that goes on top of your crushed base, our free concrete calculator gives you instant volume, bag counts, and cost estimates for slabs, footings, post holes, and more.