Templates that Map Work Tasks to Corresponding Quantity Takeoff (QTO) Dimensions
How do practitioners quantify the construction work tasks and materials related to an item of work?
Construction work tasks and materials are measured using specific units of measures, and for each of the units of measure, there are specific dimension that must be used to arrive at the quantities. For example, structural excavation for a spread footing has C.Y. as the unit of measure and is derived and computed using set dimensions such as the average area times the average depth or length times width times depth. Knowledge of the applicable work tasks, their units of measures, and the related dimensions to use in computing the quantities is all that is needed for any construction work task or construction material to be quantified. In addition, the provided template also indicates factors that need to be considered when conducting takeoff.
Here is an example of one of the templates that map work tasks to corresponding QTO dimensions. The Item of work in this example is STRUCTURAL BACKFILL WITH EXPANDED POLYSTYRENE BLOCKS
| WORK TASK | TYPICAL UNIT OF MEASURE (UOM) USED FOR QUANTITY TAKEOFF OF WORK TASKS | TYPE OF CUT, FILL, AND BACKFILL MATERIAL | STATES OF CUT, FILL, AND BACKFILL MATERIAL – CONVERTING BETWEEN BANK VOLUME, LOOSE VOLUME, AND COMPACTED VOLUME | H:V RATIO PER ALLOWABLE SIDE SLOPE OF EXCAVATION | EACH (COUNT THE PIECES) | PERIMETER | LENGTH – PER START STATION TO END STATION AT TOP ELEVATION AND/OR START STATION TO END STATION AT BOTTOM ELEVATION | WIDTH – PER WIDTH AT TOP ELEVATION AND/OR WIDTH AT BOTTOM ELEVATION | HEIGHT (OR DEPTH) PER TOP ELEVATION TO BOTTOM ELEVATION | SURFACE MAP (FROM CONTOUR LINES) AT EXISTING AND PROPOSED GRADE | VOLUME OF STRUCTURAL COMPONENTS BELOW GRADE (If Any) |
|---|---|---|---|---|---|---|---|---|---|---|---|
| PREPARE, SUBMIT, AND OBTAIN APPROVALS FOR SPECIFIED SUBMITTALS | |||||||||||
| SURVEY AND SET LINES AND GRADES | |||||||||||
| MOBILIZE AND SET UP AT LOCATION | |||||||||||
| FINE GRADE SUBGRADE SURFACE FOR GEOFOAM PLACEMENT | SY | YES | YES | YES | YES | ||||||
| PLACE AND COMPACT AGGREGATE BASE FOR GEOFOAM PLACEMENT (As Required) | CY | YES | YES | YES | YES | YES | YES | YES | |||
| CUT GEOFOAM BLOCKS TO SIZE AND SHAPE (As Required) | CY | YES | YES | YES | YES | ||||||
| PLACE GEOFOAM BLOCKS SO THAT BLOCKS FIT TIGHTLY TOGETHER WITH MINIMUM GAPS BETWEEN THE INDIVIDUAL BLOCKS | CY | YES | YES | YES | YES | ||||||
| CONSTRUCT SLOTTED OR PINNED CONNECTIONS AND CLOSELY HOLD GEOFOAM BLOCKS TOGETHER (As Required) | CY | YES | YES | YES | YES | ||||||
| FINISH PLACING GEOFOAM TO GRADE AND REQUIRED GEOMETRY | CY | YES | YES | YES | YES | ||||||
| BACKFILL BETWEEN GEOFOAM BLOCKS (As Required) | CY | YES | YES | YES | |||||||
| COVER GEOFOAM TOP AND SIDES WITH SPECIFIED FABRIC (As Required) | SY | YES | YES | YES | YES | ||||||
| CONSTRUCT REINFORCED CONCRETE BASE COURSE WITHOUT CAUSING DAMAGE TO THE UNDERLYING FABRIC AND GEOFOAM BLOCK (As Required) | CY | YES | YES | YES | |||||||
| DEMOBILIZE AND MOVE OUT OF SITE |