Concrete Curb Calculator

By Michael Woo · Updated June 2026

0.93 yd³ yd³ 100 LF · installed $2,000–$3,500 $2,000–$3,500 installed cost
BLS OEWS 47-2051 Cement Mason Wages — verified 2026-06, updates annual

Pro tips

Break the curb cross-section into rectangles for accurate volume

A standard Type B curb-and-gutter cross-section — 6-inch curb face, 14-inch gutter pan averaging 3 inches thick, and 6-inch below-grade footing extending 20 inches — totals approximately 198 square inches (1.375 sq ft). For a 100-foot run, volume = 1.375 × 100 = 137.5 cubic feet = 5.09 cubic yards. Estimating only the visible curb face underestimates total volume by 60–70%.

Add 3–5% for expansion joint filler and form radius waste

ACI 332 requires expansion joints every 20–30 feet; omitting them causes 80–90% of curb runs to crack within 3–5 frost seasons. Saw-cutting after the fact costs $200–$500 per 100 linear feet versus $500–$1,200 for replacement sections. A 90-degree driveway return with a 5-foot radius adds 5–8% more concrete per foot than a straight run; add 5% to any job with more than 2 radius sections.

Account for integral curb vs. separate pour volumes differently

Integral curb adds only 36 square inches (0.25 sq ft) of cross-section above the slab, so 100 feet of integral curb adds just 0.93 cubic yards to the slab pour. A separate curb-and-gutter with its own footing has a 150–200 square inch cross-section (1.0–1.4 sq ft), requiring 3.7–5.2 cubic yards for the same 100 feet. Using the integral formula for a separate pour under-orders by 75–80%, leaving 3+ cubic yards short.

Hidden costs

Forming material for poured-in-place curb

$0.40–$0.80 per LF for 2-inch lumber forms on straight runs, with forms reusable 3–5 times. Curved forms need flexible plastic form stakes at $0.80–$1.20 per LF and cannot be reused.

Expansion joint material

Preformed bituminous fiber expansion joint filler runs $0.15–$0.25 per LF; polyurethane joint sealant with backer rod costs $0.50–$1.00 per LF. Joints are required every 10 feet and skipping them is the primary cause of curb cracking within 3–5 frost seasons.

Sub-base compaction

A curb on soft or unstable base will settle unevenly within 1–3 seasons. Compacted 3/4-inch gravel base at $1.50–$3.00 per LF for 4-inch depth under the curb footprint prevents settling and joint separation.

Rookie mistakes

Using slab calculator formulas for curb geometry

Entering 200-foot curb dimensions into a slab calculator — 6 inches wide × 6 inches tall — returns 1.85 cubic yards. The actual volume including the 14-inch gutter pan and 20-inch footing is approximately 10.2 cubic yards for the same 200-foot run. That 8.35-cubic-yard shortfall is an entire truckload, stopping the pour at 36 feet and forcing a cold joint.

Measuring curb length along the property line instead of the actual curb path

A 60-foot property frontage with two 15-foot driveway returns has an actual curb length of 78.8 feet — 31% longer than the property line measurement. Those missing 18.8 feet at a 1.4 sq ft cross-section represent nearly 1 cubic yard of concrete. Always walk the curb path with a measuring wheel — survey plat scaling misses 15–30% of true length on lots with even 1 driveway return.

Not accounting for subgrade over-excavation filling with concrete

On a 200-foot curb run with a 20-inch-wide trench, just 3 inches of average over-excavation adds 20.8 cubic feet (0.77 cubic yards) of unplanned concrete. On runs of 500+ feet this hidden volume reaches 2+ cubic yards, consuming the typical 5% waste allowance entirely. Check trench depth with a grade rod at 25-foot intervals and adjust the concrete order upward for sections deeper than spec.

Example project costs

Driveway apron, barrier curb

50 LF · 6″ W × 6″ H · 4,000 PSI, joints at 10 ft

Concrete volume0.46 yd³
Installed (contractor)$1,000–$1,750
Total0.46 yd³ · installed $1,000–$1,750

Parking-lot perimeter

250 LF · 9″ W × 6″ H · two 20-ft-radius corners, #3 rebar

Concrete volume3.47 yd³
Installed (commercial)$5,000–$8,750
Total3.47 yd³ · installed $5,000–$8,750

Garden edge curbing (DIY)

30 LF · 12″ W × 4″ H rollover · bagged mix

Concrete volume0.37 yd³
80 lb bags (0.6 cu ft each)17 bags
Bag material (retail)$95–$135
Total0.37 yd³ · ~17 bags · $95–$135

What NOT to build with concrete curb calculator

Don't use concrete curb calculator for: Poured-in-place concrete curbing in a frost climate without saw-cutting expansion joints every 10 feet

Concrete expands and contracts approximately 0.0000055 inches per inch per degree F; without joints at maximum 10-foot intervals per ACI 360R-10, the curb cracks randomly under seasonal thermal forces. Saw-cutting joints costs $3–$6/linear foot; random crack repair runs $500–$1,200 per 100 linear feet replaced.

How to do it yourself

Concrete curbing is DIY-feasible for straight runs under 50 LF. Form with 2-inch-thick lumber (1×6 or 2×6) staked firmly on both sides every 2 feet; for radius curves above 3 feet, use 1/4-inch flexible hardboard bent around stakes. Use a 4,000 PSI mix, vibrate or rod to consolidate, strike off level with the form top, broom finish, and cure with wet burlap for 3 days minimum.

Step-by-step checklist

  • Excavate the curb footprint to 3–4 inches below final grade and compact the base
  • Set forms 6 inches apart (or per your curb width) and brace with stakes every 2 feet
  • Install preformed expansion joint filler every 10 feet before pouring
  • Consolidate the concrete in the form — rod or vibrate to eliminate voids at the corners
  • Cure for a minimum of 3 days before removing forms; 7 days before any vehicle load

When to hire a professional

A 6×6 barrier curb adjacent to vehicle traffic should be poured monolithically with the adjacent slab if possible, or at minimum have #3 rebar running its full length to resist lateral displacement. DIY attempts on runs over 50 LF or with more than 2 radius returns typically require a ready-mix truck delivery minimum of $350–$600, making professional installation cost-competitive.

Concrete curb profiles and their standard dimensions

Barrier curb (vertical-face): 6 inches wide × 6 inches tall at the front face, typically tapering to 8 inches at the base for stability — volume 0.25 sq ft cross-section, or 108 LF per cubic yard. Rollover (mountable) curb: 12 inches wide × 4 inches tall with a gradual taper; volume 0.33 sq ft cross-section (81 LF/yd³) — more concrete than barrier despite looking smaller because of the wide base. Modified barrier curb (Type B per AASHTO): 9 inches wide × 6 inches tall, default municipal spec in many US cities — 0.375 sq ft cross-section, or 72 LF per cubic yard. For the calculator, enter actual cross-section dimensions using yd³ = length × (width / 12) × (height / 12) / 27; for a curb that's 6 inches at the top face and 8 inches at the base, use 7 inches (mid-section average) as the width input.

Installed cost, reinforcing, and what moves the number on a curb job

Contractor-installed concrete curbing runs $20–$35 per linear foot for residential and light commercial work; the breakdown is concrete material ($1.00–$1.50/LF for a 6×6 barrier curb at $130–$180/yd³ ready-mix), forming labor ($6–$10/LF), pour and finish labor ($8–$12/LF for a cement mason at BLS median $24.14/hr), and contractor overhead ($5–$7/LF). Curved sections take 3–4 times longer to form than straight runs, pushing tight-radius jobs to the $35/LF ceiling. Most residential curbing is unreinforced, but DOT specs for roads subject to vehicle impact typically require #3 rebar on 18-inch centers — 100 LF of rebar adds $25–$40. Expansion joints every 10 feet are non-negotiable in frost climates; skipping them or spacing wider than 10 feet is the leading cause of random cracking, with repair costs of $500–$1,200 per 100 LF.
How this is calculated

Formula: yd³ = length × (width ÷ 12) × (height ÷ 12) ÷ 27; installed $20–$35/LF poured-in-place (BLS OEWS 47-2051 cement mason $24.14/hr)

InputValueUnit
Curb length 100 ft
Curb width 6 in
Curb height 6 in

Frequently Asked Questions

How much concrete do I need for 100 linear feet of curb?

For a standard 6-inch wide × 6-inch tall barrier curb: 100 LF × (6/12 ft) × (6/12 ft) / 27 = 0.93 yd³; round up to 1.0 yd³ for waste. At 80-lb bags (0.60 cu ft each): 100 LF × 0.25 cu ft/LF / 0.60 = 42 bags. Enter your specific width and height in the calculator above — a 9" × 6" profile on the same 100 LF run yields 1.39 yd³, 49% more material.

What are the standard dimensions for a residential concrete curb?

The most common residential profiles: barrier curb (6" wide × 6" tall, 108 LF/yd³), rollover/mountable curb (12" wide × 4" tall, 81 LF/yd³), and modified barrier curb (9" wide × 6" tall, 72 LF/yd³). For projects adjacent to a public street, match your local DOT standard detail — most municipal specs call for a minimum 3,500 PSI mix and vary face height by 1–3 inches between jurisdictions.

How much does concrete curb installation cost per linear foot?

Contractor-installed concrete curbing costs $20–$35/linear foot for residential and light commercial in most US markets. Straight runs on flat, accessible ground land at $20–$25/LF; curved sections, tight access, or reinforcing requirements push to $30–$35/LF. Minimum job charges of $500–$800 apply on most small projects regardless of total LF.

Can I pour concrete curbing myself?

Yes, for straight runs under 50 LF: form with 2-inch-thick lumber staked every 2 feet, pour 4,000 PSI mix, broom finish, and cure 3 days. Material cost for a 50 LF × 6" × 6" run is approximately 21 bags (80 lb) at $6.50–$9.00 each = $137–$189 in concrete, plus $25–$40 in lumber forms.

What is the difference between a barrier curb and a rollover curb?

A barrier curb has a near-vertical 6-inch face that physically stops most vehicles and will damage a tire or wheel if struck at speed. A rollover curb has a gradual 12-inch wide × 4-inch tall slope that vehicles can drive over at low speed without damage. Use barrier curb for pedestrian protection; use rollover for driveways, parking lot medians, and any location where vehicles need regular access at under 10 mph.

How long does concrete curb take to cure before driving on it?

The curb reaches approximately 70% of design strength in 7 days at 70°F per ACI 209R-92; most contractors allow 7 days before vehicle load. In cold weather below 50°F, extend cure time by 30–50%. Foot traffic is fine after 24–48 hours once the surface is hard.

Sources

  1. BLS OEWS 47-2051 Cement Mason Wages — verified 2026-06, updates annual