Mix design and PSI
Standard residential flatwork often uses 3,000 to 4,000 PSI ready-mix, while structural or exposure-driven projects may need stronger mixes, additives, or air entrainment. Those upgrades usually increase cost per yard.
Order size
Small orders cost more per yard because dispatch still has truck time, plant handling, and cleanup overhead. That is why short-load fees matter on patios, pads, and repair work.
Site access and labor
A straight truck chute to a simple slab is cheaper than wheelbarrow work, pump work, or a pour with difficult access. Finishing complexity, weather, slope, and edge detailing also change labor cost quickly.
Reinforcement and prep
Rebar, wire mesh, fiber mix, gravel base, vapor barrier, and formwork are common add-ons. For realistic budgeting, those items should be estimated separately instead of buried inside one guessed number.