#8 Rebar Calculator — 1 Inch Heavy Structural Bar
Estimate #8 (1-inch) rebar bar count and weight for engineered structural columns, large beams, and heavy commercial footings per ASTM A615 specifications.
Enter Dimensions
Add 10% for standard cuts and overlaps
Results
Bars Needed
38bars
Total Lineal Feet
608lin ft
Total rebar length including waste
Total Weight
406lb
#4 rebar weight per CRSI
Slab Area
240sq ft
Editorial Standards
Each calculator is reviewed for formula accuracy, unit consistency, and alignment with current U.S. building practices before publication. We verify outputs against published engineering references and real-world project data. Learn more about our methodology.
#8 rebar (1 inch diameter) is the heaviest standard rebar size for residential and light commercial work. It's an engineered choice only — never substitute for smaller bars without re-engineering. Common applications: grade beams, columns, transfer beams, deep footings under bearing concentration loads, and seismic structural frames.
For typical residential reinforcement, see the #4 or #5 Rebar calculator.
How to Estimate #8 Rebar
LF = Pieces × Length. Weight = LF × 2.670 lb/ft. Class B Lap = 40 in.
#8 Rebar Quick Reference
- Diameter: 1 inch (1.000 in)
- Weight: 2.670 lb/ft (53.4 lb per 20 ft stick)
- Steel area: 0.79 sq in
- Min bend dia: 6 in
- Class B lap splice: 40 in
- Cost: ~$1.80-2.80/LF (2025)
- Use: engineered structural elements only
- Availability: commercial supplier order, 1-2 week lead time
Frequently Asked Questions
What is #8 rebar used for?
#8 rebar (1 inch diameter) is engineered structural reinforcement: large columns, heavy beams, commercial footings, retaining walls 10+ ft tall, and seismic moment frames. Always specified by an engineer — not a prescriptive code choice.
How much does #8 rebar weigh?
2.670 lb per linear foot — 4× the weight of #4. A 20 ft stick weighs 53 lb; a 40 ft stick weighs 107 lb. Mechanized handling is essentially required.
How much does #8 rebar cost?
$1.80-2.80 per LF in 2025 — 4× the cost of #4 by foot. A 20 ft stick: $36-56. By the ton: $900-1,400, similar per pound to smaller bars.
Is #8 rebar available at home centers?
Rarely — most home centers stock #3 through #6. #8 typically requires order from a commercial rebar supplier with 1-2 week lead time. Pre-bent shapes need a fabricator.
Can residential projects use #8 rebar?
Only where engineered drawings specify it. Common residential applications: large grade beams under bearing walls on soft soil, columns supporting 2-story bearing concentration loads, deep footings under transfer beams. Always pair with an engineer's review.
Looking for the general calculator?
Calculate rebar quantity, spacing, and total weight for concrete slabs, footings, and walls. Covers #3 through #8 bar sizes using CRSI published weight tables.
Open the Rebar Calculator: Bar Count & Weight →