Why is the wet mortar taken as 0.0150 m^3 per m^2 instead of 0.0125 m^3?

20% is added for filling uneven wall surface and wastage

20% is added because dry mortar swells on mixing

The thickness is increased to 15 mm for 1:5 mortar

It covers the contractor's overhead and profit

For 10 m^2 the dry mortar is 0.1950 m^3. How is the cement volume found for mortar 1:5?

0.1950/6 = 0.0325 m^3, since the ratio parts sum to 6

0.1950 x 1/5 x 1.30 = 0.0507 m^3

The total for 10 m^2 including 15% overhead and profit is Rs 4,333.95. What is the rate per m^2?

Rs 433.39, by dividing the 10 m^2 total by 10

Rs 4,333.95, as the rate is the total

Rs 3,768.65 / 10 = Rs 376.87, as overhead is excluded

Rs 4,333.95 x 10 = Rs 43,339.50

Asked 3/22
2081 Bhadra · 5 marks

Rate analysis: 12.5 mm plaster 1:5, per m²

Short answer

Based on 20% wastage and 1.30 dry factor, dry mortar is 0.0195 m3/m2. For 10 m2, cement 0.936 bags and sand 0.1625 m3. Rate = Rs 433.39 per m2, including 15% overhead.

Prepare analysis of rate for 12.5 mm thick plaster with (1:5) cement sand mortar per 1 m².

Basis

12.5 mm thick plaster in cement mortar 1:5 on brick wall, worked for 10 m² and divided by 10. Rates are illustrative.

Mortar quantity

Wet volume per m² = 0.0125 m³; add 20% for filling uneven wall surface and wastage: 0.0150 m³.
Dry mortar = 0.0150 x 1.30 = 0.01950 m³ per m².
For 10 m²: dry mortar = 0.1950 m³; cement = 0.1950/6 = 0.03250 m³ = 46.8 kg = 0.936 bags; sand = 0.1625 m³.

Analysis (per 10 m²)

Description	Qty	Unit	Rate (Rs)	Amount (Rs)
Cement (0.03250 m³)	0.936	bag	900.00	842.40
Sand (0.1625 m³)	0.1625	m³	2,500.00	406.25
Mason (skilled)	1.2	md	1,200.00	1,440.00
Helper (unskilled, incl. water and scaffolding)	1.2	md	900.00	1,080.00
Sub-total				3,768.65
Contractor's overhead and profit	15%			565.30
Total per 10 m²				4,333.95

Answer: Rate of 12.5 mm 1:5 plaster = 4,333.95 / 10 = Rs 433.39 per m² (excluding VAT).

✓ Answer checked by Claude Opus 5.5 (high effort)

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Rate analysis: 12.5 mm plaster 1:5, per m²

Basis

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Analysis (per 10 m²)

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