Concrete contractors glossary
Short, plain-English definitions of the terms you'll meet when choosing a concrete contractor provider in Charlotte Metro.
- What is a broom finish?
- A broom finish is a textured concrete surface created by dragging a broom across freshly poured concrete while it is still wet, producing a slip-resistant pattern commonly used on driveways, patios, and walkways.
- What is a concrete overlay?
- A concrete overlay is a thin layer of new concrete bonded to an existing slab to refresh, repair, or restyle the surface without removing the base.
- What is a concrete sealer?
- A protective coating or penetrating treatment applied to concrete surfaces to resist water infiltration, staining, and weathering damage.
- What is a control joint?
- A control joint is a deliberately cut groove in concrete that directs cracks to occur in predictable locations, preventing random and damaging fractures across the surface.
- What is a curing compound?
- A liquid membrane applied to fresh concrete surfaces that reduces water evaporation and allows proper cement hydration to develop concrete strength.
- What is a foundation footing?
- A foundation footing is the below-grade structural base that distributes a building's load across stable soil or rock, sized to prevent frost heave and settlement.
- What is a frost line?
- The frost line is the maximum depth to which soil freezes during winter; building codes require concrete footings to extend below this depth to prevent frost heave damage.
- What is a slump test?
- A slump test measures how far wet concrete settles when a cone mold is lifted, indicating the mix's workability and moisture content.
- What is a trowel finish?
- A trowel finish is a smooth concrete surface produced by running a hand or power trowel across freshly set concrete to flatten the top layer and create a clean, even appearance.
- What is a vapor barrier?
- A vapor barrier is a layer of polyethylene sheeting placed beneath concrete slabs to block moisture rising from the ground.
- What is air-entrained concrete?
- Air-entrained concrete is concrete mixed with an admixture that creates millions of tiny, evenly distributed air voids, improving resistance to freeze-thaw cycles and road salt damage.
- What is an expansion joint?
- An expansion joint is a deliberately created gap filled with flexible material that allows concrete slabs and structures to expand, contract, and settle without cracking.
- What is an exposed aggregate finish?
- Exposed aggregate is a concrete finish where the surface paste is washed away to reveal the underlying decorative stone particles, creating a textured and slip-resistant surface.
- What is concrete mix design?
- Concrete mix design is the precise formula of cement, aggregates, water, and additives proportioned to achieve required strength, durability, and workability for a specific construction application.
- What is efflorescence?
- Efflorescence is a white, chalky mineral deposit that appears on concrete surfaces when moisture moves through the slab and carries dissolved salts to the surface, where they crystallize.
- What is fiber-reinforced concrete?
- Concrete that contains synthetic or steel fibers dispersed throughout the mix to reduce shrinkage cracks and improve structural integrity.
- What is grading and site prep?
- Grading and site prep is the process of leveling, compacting, and sloping soil to create a stable, well-draining foundation before concrete is poured.
- What is PSI in concrete strength?
- PSI (pounds per square inch) is the unit that measures how much compressive force concrete can withstand before breaking, determining its structural capacity for different applications.
- What is rebar vs wire mesh?
- Rebar (reinforcing steel bars) and wire mesh are two methods of reinforcing concrete to prevent cracking and increase structural strength, often used together or separately depending on the application and soil conditions.
- What is self-leveling concrete?
- Self-leveling concrete is a pourable, low-viscosity cement-based material that flows across an uneven substrate and hardens into a smooth, flat surface before final flooring or coatings are applied.
- What is spalling in concrete?
- Spalling is the breaking away of surface layers from concrete due to freeze-thaw damage, salt exposure, or internal rebar rust pushing outward.
- What is subgrade vs subbase?
- Subgrade is the compacted native soil layer directly beneath a concrete slab, while subbase is the gravel or crushed stone layer placed on top of the subgrade to improve drainage and stability.
- What is the difference between mudjacking and polyurethane foam leveling?
- Mudjacking and polyurethane foam leveling are two concrete-lifting techniques that inject material beneath sunken slabs to restore grade, differing in their base material, weight, and curing speed.
- What is the difference between stamped concrete and stained concrete?
- Stamped concrete uses molds and pressing tools to imprint patterns and textures into fresh concrete, while stained concrete applies chemical or water-based dyes to add color to existing surfaces. These are two distinct finishing methods that are frequently combined.