- 2081 Baisakh · 4×4 marks
Double room: excavation, CRS, brick, plaster
Short answer
Using an assumed double-room layout, centre-line method gives excavation 36.30 m³, crushed rubble stone masonry 10.54 m³, first-class brickwork 21.70 m³, and 12 mm inner plaster 80.46 m².
Calculate the quantities from the given building drawings: Fig. 1(a, b) a) Earthwork in excavation b) Crushed rubble stone masonry c) 1st class brick work in super structure d) 12 mm plastering work 1:4 for inner wall Following are the double room building estimation specifications:
- In foundation cement concrete M25 is used.
- CRS wall is used in the foundation for the base of the brick wall.
- Plinth beam size is 400 mm × 600 mm in cement concrete M25.
- Damp-proof course 25 mm thick is applied.
- In superstructure 1st class brickwork is in 1:4 cement mortar and thickness 300 mm.
- Doors D, size 1.2 m × 2.1 m
- Windows W, size 1 m × 1.5 m
- Shelves S-1 m × 1.5 m [Fig. 1(a, b) not included in the scanned paper]
Fig. 1 is not available, so an assumed double-room building is used with the given specifications.
Assumed data
- Two rooms side by side, each 4.0 m × 3.5 m clear; all walls 300 mm (as stated). Outside size = (2 × 4.0 + 3 × 0.3) × (3.5 + 2 × 0.3) = 8.90 × 4.10 m.
- Centre-line length of outer walls = 2[(8.90 − 0.3) + (4.10 − 0.3)] = 24.80 m. The partition is 3.5 + 0.3 = 3.80 m between the centre lines of the outer walls; at each of its two T-junctions it is shortened by half the width of the outer-wall item, so its length is 3.80 − 1.10 = 2.70 m for the trench, 3.80 − 0.50 = 3.30 m for the CRS and 3.80 − 0.30 = 3.50 m for the brickwork.
- Foundation: trench 1.10 m wide, 1.20 m deep; CC M25 bed 0.30 m; CRS wall 0.50 m wide, 0.75 m high from top of bed to bottom of plinth beam (0.15 m below GL); plinth beam 400 × 600 mm (not asked).
- Superstructure 3.0 m high above plinth beam; D 1.2 × 2.1 (2 nos.), W 1.0 × 1.5 (3 nos.), shelf recess S 1.0 × 1.5 × 0.15 m deep (2 nos.). Plaster 12 mm 1:4.
a) Earthwork in excavation
| Item | No. | L (m) | B (m) | H/D (m) | Qty (m³) |
|---|---|---|---|---|---|
| Trench, outer walls | 1 | 24.800 | 1.100 | 1.200 | 32.736 |
| Trench, partition (3.80 − 1.10) | 1 | 2.700 | 1.100 | 1.200 | 3.564 |
| Total | 36.300 |
b) Crushed rubble stone masonry
| Item | No. | L (m) | B (m) | H/D (m) | Qty (m³) |
|---|---|---|---|---|---|
| CRS masonry, outer walls, 0.50 wide × 0.75 high | 1 | 24.800 | 0.500 | 0.750 | 9.300 |
| CRS masonry, partition (3.80 − 0.50) | 1 | 3.300 | 0.500 | 0.750 | 1.238 |
| Total | 10.538 |
(For reference, M25 concrete bed = (24.80 + 2.70) × 1.10 × 0.30 = 9.08 m³.)
c) 1st class brick work in superstructure (1:4)
| Item | No. | L (m) | B (m) | H/D (m) | Qty (m³) |
|---|---|---|---|---|---|
| Wall 0.30 × 3.0 above plinth beam (24.80 + 3.50) | 1 | 28.300 | 0.300 | 3.000 | 25.470 |
| Deduct doors D 1.2 × 2.1 (2 nos.) | -2 | 1.200 | 0.300 | 2.100 | -1.512 |
| Deduct windows W 1.0 × 1.5 (3 nos.) | -3 | 1.000 | 0.300 | 1.500 | -1.350 |
| Deduct shelves S 1.0 × 1.5 × 0.15 recess (2 nos.) | -2 | 1.000 | 0.150 | 1.500 | -0.450 |
| Deduct lintels over doors | -2 | 1.600 | 0.300 | 0.150 | -0.144 |
| Deduct lintels over windows and shelves | -5 | 1.400 | 0.300 | 0.150 | -0.315 |
| Total | 21.699 |
d) 12 mm plastering, 1:4, inner wall
| Item | No. | L (m) | B (m) | H/D (m) | Qty (m²) |
|---|---|---|---|---|---|
| Inside walls, both rooms 2 × 2(4.0+3.5) × 3.0 | 1 | 30.000 | 3.000 | – | 90.000 |
| Deduct doors (one inside face each) | -2 | 1.200 | 2.100 | – | -5.040 |
| Deduct windows | -3 | 1.000 | 1.500 | – | -4.500 |
| Total | 80.460 |
Answer: Excavation 36.30 m³; CRS 10.54 m³; brickwork 21.70 m³; plaster 80.46 m² (assumed layout).
✓ Answer checked by Claude Opus 5.5 (high effort)
Related questions
- Load bearing building: excavation, brick, plaster · Estimating and Costing, chapter 6
- Two-room building: excavation, PCC, brick, plaster · Estimating and Costing, chapter 6
- One-roomed building: earthwork, plaster, openings · Estimating and Costing, chapter 6
- Building: excavation, brick, paneled door, plaster · Estimating and Costing, chapter 6
- Building: excavation, PCC, brick, wood work · Estimating and Costing, chapter 6
- Two-room building: brick plinth, door shutters, plaster · Estimating and Costing, chapter 6
- Rubble, coursed rubble and ashlar masonry · Building Technology, chapter 3 · asked 2×
- Specifications of brick masonry work · Building Technology, chapter 3 · asked 2×
- Retrofitting a brick masonry building · Building Technology, chapter 11
- Random rubble and dry rubble masonry · Building Technology, chapter 3