Square feet (SF)
Square feet measure surface area and are commonly used for drywall, painting, flooring, ceilings, roofing and insulation. Estimators must distinguish gross area from net area and document deductions, laps and waste.
Linear feet (LF)
Linear feet measure length and apply to items such as curbs, trim, piping, conduit, joints and railings. Size, material and installation condition should remain separate because equal lengths can have very different costs.
Square yards (SY)
Square yards frequently appear in civil work, paving, milling, geotextiles and some flooring. One square yard equals nine square feet, but thickness and material density may still be needed to convert the area into volume or tons.
Cubic yards (CY)
Cubic yards measure volume for concrete, excavation, aggregate and backfill. Calculations should state dimensions, swell or compaction assumptions and whether waste or over-excavation is included.
Each (EA)
Each counts fixtures, doors, devices, equipment and other discrete components. The description should identify type, size, capacity and accessories so a simple count does not hide scope differences.
Why measurement descriptions matter
A quantity becomes priceable only when the unit and item description match how the work is purchased and installed. Professional takeoffs pair measurements with drawing references, specifications and scope notes.