Rebar
Deformed steel reinforcing bar cast into concrete to carry tension the concrete cannot. Sized in eighths of an inch — a #4 bar is 4/8 inch and weighs 0.668 lb per foot. Slab grids are laid both ways at 12–18 inch spacing.
Where this appears in real estimates
This term isn't trivia — it's a working variable. These tools use it directly:
- rebar calculator — Rebar bar count, linear feet and weight for slab grids by spacing.…
- concrete slab calculator — Slab volume in cubic yards with bag counts and standard thickness presets.…
- concrete footing estimate tool — Cubic yards for strip and pad footings from length, width and depth.…
Go deeper
- Bagged Concrete vs Ready-Mix — head-to-head decision guide
- Yard Drainage Fix — full project walkthrough
- Excavation in Pennsylvania — local pricing & climate
- Read the field guide on the blog — practitioner-level detail
- Related engineering article — from our licensed engineer
Reviewed: · Part of the CalculatorAsphalt Construction Glossary · Sources: see methodology & standards.