What is CY (cubic yard) in construction?

The cubic yard shows up anywhere volume is bought or moved: ready-mix concrete tickets, earthwork cut and fill summaries, aggregate base quotes, demolition haul-off, and landscaping soil. Concrete subs price placement by the cy, excavation contractors price digging and hauling by the cy, and trucking capacity is rated in cy. The unit matters because suppliers sell in it while drawings dimension in feet and inches, so every takeoff includes the conversion step. New estimators trip on three things: forgetting to divide cubic feet by 27 (not 9, that is square yards), mixing inches and feet in the same multiplication, and treating earthwork volumes as one number when bank, loose, and compacted cubic yards differ because soil swells when dug and shrinks when compacted. A clean estimate states which condition the cy quantity represents and applies swell or shrink factors deliberately.

For concrete, take the plan area in square feet times the thickness in feet to get cubic feet, then divide by 27. Slabs, footings, walls, and columns are each computed from their own dimensions and summed. For earthwork, cut and fill volumes come from comparing existing and proposed grades, often by the average end area method or grading software. Estimators then add a waste factor for concrete (spillage, over-excavation, uneven subgrade) or a swell or shrink factor for soil, and round up to the supplier's ordering increment.

Figures on this page are illustrative. Construction estimates depend on project-specific conditions, source documents, market pricing, and professional judgment. Ruh's AI assists the estimator and does not replace professional review: your team reviews, validates, and approves every estimate, bid, and pricing decision.