Test: Estimation and Costing - Civil Engineering (CE) MCQ

Purpose of Analysis of rates: 

• To work out the actual cost per unit of the items at the locality.
• To examine the viability of rates offered by contractors
• To calculate the number of materials and labor strength required for project planning
• To fix labor contract rates
• To work out the economical use of materials and processes in completing the particulars item.
• To work out the cost of extra items which are not provided in the contract bond, but are to be done as per the directions of the department.
• To revise the schedule of rates due to an increase in the cost of material and labour or due to a change in technique. 

Additional Information
Cost of labor -types of labour, standard schedule of rates: 

• The labour can be classified into 1) Skilled – 1st class 2) Skilled – 2d Class 3) Unskilled
• The labour charges can be obtained from the standard schedule of rates 30% of the skilled labour provided in the data may be taken as Ist class, remaining 70% as II class.
• The rates of materials for Government works are fixed by the superintendent Engineer for his circle every year and approved by the Board of Chief Engineers. These rates are incorporated in the standard schedule of rates. 

Height of wall = 4 m
Thickness of wall =20 cm = 0.2 m.
Window area = 0
Door area = 0
Total opening area = 0 (As, window area and door area is not given)
Net effective area, where brickwork is to be done is given as:
= (Centreline length) × Height – opening area
= 4 × 5 - 0 = 20 m²
Qty o f brick work = (effective area) × Thickness of wall
= 20 × 0.2
= 4 m³

• Damp Proof Course or DPC is the protective layer applied to prevent the rising of moisture to the walls from the ground due to capillary action.
• It is usually 2.5 cm thick with a ratio of rich cement concrete 1:1.5:3 or 2 cm thick with cement mortar 1:2 mixed with standard waterproofing material.
• It is provided from the plinth level to the entire width of the plinth wall, and the quantities are calculated in square meters (length x breadth). 

Some common materials used in the Damp Proof Course:

• Hot bitumen – This is a highly flexible material with a minimum thickness of 3 mm. It is applied to the bedding of concrete or mortar while it is hot.
• Mastic asphalt – It is a semi-rigid, highly durable, and entirely waterproof material. It’s made by heating asphalt, sand, and mineral fillers together. 
• Bituminous or asphaltic felts – This is a flexible material that is available in rolls of various wall thicknesses. It is applied on a uniform flat layer of cement mortar.
• Metal sheets – Lead, copper, and aluminum sheets can be utilized as DPC. These sheets are made of a flexible material and are pretty flimsy. Their thickness should be such that their weight per square meter does not go below 20 kg/m².

Additional Information
Dampness in buildings can lead to the attack of termites, rusting and corrosion of metal fittings, cracking in walls, electrical fittings getting damaged, leaking sealants, and many more problems that can lead to loss of money when not treated in time.