Steel bars embedded in concrete to increase tensile strength, since concrete is strong in compression but weak in tension.
Rebar (reinforcing bar) is ridged steel bar used to reinforce concrete structures. Concrete handles compression well but cracks under tension — rebar resists those tensile forces.
Typical spacing: 12"–18" on center for slabs, 6"–12" for walls and footings. Always check local building codes.
A measurement of area in square feet, commonly used for rooms, homes, and land in the United States.
The amount of concrete needed for a project, typically measured in cubic yards or cubic meters.
A unit of lumber volume equal to a piece 1 foot long, 1 foot wide, and 1 inch thick (144 cubic inches).
A paste of cement, sand, and water used to bind bricks, blocks, or stones in masonry construction.
A construction panel made of gypsum plaster pressed between two sheets of paper, used for interior walls and ceilings.
A unit of measurement equal to 100 square feet, used in the roofing industry to estimate materials.