Building · measured in cum
Measuring PCC for RA bills
PCC is measured as the net volume laid, from the length, breadth and thickness shown on the drawing, under footings, walls and floors.
Unit of measurement
Plain cement concrete (PCC) in foundations is measured in cum. PCC is measured as the net volume laid, from the length, breadth and thickness shown on the drawing, under footings, walls and floors.
The BOQ item description decides the unit and what the rate includes. Where the BOQ and this guide differ, the BOQ and the contract's mode of measurement win.
What is measured
- Length and breadth of each bed as laid, limited to the drawing dimensions.
- Thickness as specified on the drawing, checked at site before the next layer is placed.
- Separate items for different mixes (1:4:8, 1:3:6, 1:2:4) and for different locations if the BOQ splits them.
- Levelling course and mud mat only where the BOQ has an item for them.
Standard deductions
- Ends of dissimilar materials and small embedded items are commonly not deducted, as per the contract's mode of measurement and the relevant part of IS 1200.
- Concrete laid beyond the drawing size, or thicker than specified, is not paid.
- Volumes occupied by pipes or openings above the size set in the contract are deducted.
Worked example
Ward office building, PCC 1:4:8 with 40 mm aggregate, 100 mm thick under footings and the wall trench.
| Location | Nos | L | B | D | Qty (cum) |
|---|---|---|---|---|---|
| Under footings F1 | 6 | 2.40 | 2.40 | 0.100 | 3.456 |
| Under footings F2 | 4 | 2.00 | 2.00 | 0.100 | 1.600 |
| Wall trench, grid A | 1 | 18.50 | 0.80 | 0.100 | 1.480 |
| Total | 6.536 |
Row by row: Under footings F1, 6 x 2.4 x 2.4 x 0.1 = 3.456; Under footings F2, 4 x 2 x 2 x 0.1 = 1.600; Wall trench, grid A, 1 x 18.5 x 0.8 x 0.1 = 1.480.
Total: 3.456 plus 1.600 plus 1.480 = 6.536 cum. Deductions are entered with negative nos, so they reduce the total in the same column.
Common disputes
- Thickness is claimed as specified, but the client's engineer finds a thinner bed on a test pit.
- PCC under footings is claimed at pit size, while the drawing shows it at footing size plus a small offset.
- Mud mat is billed under the PCC item when the BOQ has no item for it.
Recording it in Tatha Vastu
Each bed is one entry linked to the PCC item, with a photo of the thickness gauge or level staff. The site app checks the entry against the BOQ unit and warns when the cumulative quantity passes 80% of the BOQ quantity.
Approved entries are locked, and a correction becomes a new version with its reason. See the measurement book, or use the measurement sheet template if you still keep the register in Excel.
Should PCC be measured at the pit size or the footing size?
At the size shown on the drawing for the PCC bed. That is often the footing size plus a small projection, not the full pit.
Is wastage paid?
No. Wastage is part of the rate. Only the net volume to drawing dimensions is measured.
How should a thicker bed be billed?
At the drawing thickness. Extra thickness is paid only if the engineer-in-charge ordered it in writing, and then it should be recorded with that reference.