What is Bill of Quantities (BOQ)

Bill of Quantities also referred to as BOQ, is a document formulated in the construction industry to specify materials, labors, and their cost. It serves as a communication tool between client, consultant & the contractor. It is usually prepared by a cost consultant or a surveyor.  Primarily there are two types of BOQs

• Bill of Materials
• Bill of Labour

Basic Format for preparing BOQ

The main sections included in the bill of quantities are Form of Tender, Information, Requirements, Pricing schedule, Provisional sums, and Day works. For the preparation of BOQ, 5 main components are to be considered which are as follows:

1. Item Description
2. Unit
3. Quantity
4. Rate per unit
5. Total Amount

Process of preparation of BOQ for RCC

Taking off Quantities:

Taking off is the process of analysing the drawing and its specifications to identify the elements required for the preparation of BOQ.

Description:

In this step, the appropriate narrative of a particular work is provided to explain and justify the work being done.

Working Up:

This step includes recording every measurement required into a sheet called the TDS Sheet. The times column (multiplier column) is for filling up the number of repetitions of the same work. It depicts the factor of multiplication. Dimension column is the one where all the dimensions like length, width & depth are recorded. Whereas in the Sums column we simply multiply the previous elements (Multiplication factor x Dimension) to get the total quantity of the work.

Calculation of materials for Reinforced Concrete Construction  

Materials requires for reinforced concrete are cement, sand, coarse aggregate and steel. Let us assume a standard quantity of 1m3 Cement mortar and a mix proportion of 1:1.5:3 (1 part Cement, 1.5 parts Sand & 3 parts CA). The quantity can preferable calculated by two methods, which are weight & volume method.

Let us consider the volume method for reinforced concrete construction. Dry volume of total materials is equivalent to 1.54 times the volume of wet concrete. Hence let us take the quantity of cement mortar as 1.54 m3.

Quantity of cement

The formula to calculate the volume of cement is as follows:

(1.54×1)/(1+1.5+3)=0.28 m^3

Since the cement is available in bags, volume of 1 cement bag is 0.0347 m3.

0.28/0.0347=8.07 bags of cement