A) Plinth area rate method
Problem no. 1) Prepare approximate estimate of new building having a plinth area is 2000 sq.m. The similar building is constructed nearby area having a plinth area is 2500 sq.m. and their cost of the building is 1,82,00,000/-.
Solution:-
Calculation of plinth area rate of similar constructed building:-
- Cost of building - 1,82,00,000/-
- Plinth area – 2500 sq.m.
Plinth area rate = Cost of building / Plinth area
= 1,82,00,000 / 2500
= 7280/- per sq.m.
Approximate cost of new building:-
- Plinth area – 2000 sq.m.
- Plinth rate – 7280/- per sq.m.
= 2000 × 7280
= Rs. 1,45,60,000/-
Approximate estimate of a new building is Rs. 1,45,60,000/-
Problem No. 2) Prepare approximate estimate of office building having a plinth area is 1600 m2. The following details are assumed to prepare an approximate estimate.
- The plinth area rate is Rs. 3000 per m2.
- Water supply and sanitary connection — 6% of cost of building.
- Electrification work — 8% of cost of building.
- Contingencies — 4% of overall cost of building.
- Supervision charges — 7% of cost of building.
- Other services — 5% of the cost of building.
Solution:-
- Plinth area – 1600 m2.
- Plinth area rate – Rs. 3000 per m2
1) Cost of construction =
Plinth area × Plinth area rate
= 1600 × 3000
= Rs. 48,00,000/-
2) Water supply and sanitary connection – 6% of cost of building.
= 6/100 × 48,00,000
= 2,88,000/-
3) Electrification work — 8% of cost of building.
= 8/100 × 48,00,000
= 3,84,000/-
4) Other services — 5% of the cost of building.
= 5/100 × 48,00,000
= 2,40,000/-
Overall cost of building =
Cost of construction + Water supply and sanitary connection + Electrification works + Other services
= 48,00,000 + 2,88,000 + 3,84,000 + 2,40,000
= Rs. 57,12,000/-
Add Contingencies — 4% of overall cost of building.
= 4/100 × 57,12,000
= Rs. 2,28,480/-
Add Supervision charges — 7% of cost of building.
= 7/100 × 57,12,000
= 3,99,840/-
Final total
= Overall cost of building + Contingencies + Supervision charges
= 57,12,000 + 2,28,480 + 3,99,840
= Rs. 63,40,320/-
Approximate estimate of a office building is Rs. 63,40,320/-
2) Cubic content method
Using the cubic content method prepares an approximate estimate of new residential building having a plinth area is 2000 sq.m. and height of the building is 20 m above ground level. The similar building is constructed nearby area having a plinth area is 1600 sq.m. and the height of the building is 20.4 m. and their cost of the building is Rs. 6,10,00,000/-.
Solution:-
Calculation of cube rate of similar constructed building:-
Volume of building = A × H
= 1600 × 20.4
= 32640 m3
cube rate of similar constructed building
= Cost of construction / Volume of building
= 6,10,00,000 / 32640
= Rs. 1869 per m3
Cost of new building
= Volume of new building(A × H) × Rate per m3
= (2000 × 20) × 1869
= Rs. 7,47,60,000/-
Approximate estimate of new residential building is Rs. 7,47,60,000/-.
3) Service unit method
Problem No. 1) Using the service unit method, prepare an approximate estimate of new hospital building of 140 beds. The similar hospital building of 130 beds is constructed nearby area having, the construction cost of this hospital building is Rs. 35,00,000/-.
Solution:-
- Cost of similar constructed hospital building = Rs. 35,00,000/-
- No. of bed in hospital = 130 beds
Cost per bed = Cost of construction / No. of beds
= 32,00,000 / 130
= Rs. 24,615/-
Calculation of new hospital building:-
Construction cost = No. of service unit × cost per service unit
= 140 × 24,615
= Rs. 34,46,100/-
Approximate estimate of new hospital building is Rs. 34,46,100/-
Problem No. 2) Prepare approximate estimates for 4 span bridge length is 45 m each, the cost of the similar bridge is Rs. 45,000/- per meter.
Solution:-
- No of bays – 4
- Length of each span – 45 m
- Cost of similar bridge – 45,000
= 180 m
Cost of new bridge = Total length of bridge × Cost of similar bridge
= 180 × 45,000
= Rs. 81,00,000/-
Approximate estimate of bridge is Rs. 81,00,000/-
Tags:
Estimation and Costing