What Is Bill Of Quantities (BOQ)?
Bill of Quantities (bill of quantity), also known as “BOQ” or “BQ” in short, is a document prepared by a quantity surveyor, or cost consultant that provides the data of quantity of materials, labours, and their costs in construction work.
Bill of Quantities (BOQ) is an important inclusion in the tender. A tender is incomplete without a proper Bill of Quantities. It usually contains the description of work, quantity of work, materials used, labours deployed, etc. This information and data help the contractors to quote the rates for their respective work.
BOQ helps in easy assessment and comparison of price quotations of various contractors and also helps in selecting the best alternative out of all. A Bill of Quantities makes the work run smoothly without any complexities. Sometimes, a Bill of Quantities is used to take a reference for future projects.
Objectives of Bill of Quantities.
The objectives of BOQ are as follows:
1. To provide suﬃcient and precise information on the work to be performed, to enable bids to be prepared accurately.
2. To systematize the tendering process.
3. To provide a detailed idea regarding the work and its rates, and also the final amount.
Importance of Bill of Quantities (BOQ)
1. Bill of Quantities is one of the most important documents used in the construction industry.
2. It gives a proper idea to the contractor to quote the precise rate for the same information.
3. A Bill of Quantities gives a specific idea regarding the whole project on which a contractor has to work on.
4. BOQ describes the scope of work to be completed, in the respective areas of work. For example, an agency filling the tender for plaster work can have a detailed idea about its work like specifications, unit rate of work, completion time, etc.
5. BOQ provides a base to the client for valuation, tender comparison, and contract comparison.
6. It is important for preparing the final bill for the contractors.
General Format of a BOQ
Like the other documents, a BOQ also has a general format. This includes heads like:
- Serial number
- Description of work/item description
- Unit/unit of measurement
- Rate per unit (sometimes in figures and words, both)
- Total amount
- Remarks (if any)
All of these heads are the major components of a BOQ, mentioned in a systematic and presentable manner, in the Bill of Quantities. The general format of a BOQ is as follows:
|Sr. No.||Description of work||Quantity||Unit||Rate per unit||Total amount||Remarks, if any|
How To Prepare Bill Of Quantities
Preparing a BOQ involves three main steps. They are as follows:
- Describing work
- Quantity take oﬀ
- Describing the rates per unit of work.
1. Describing Work
This is the first and foremost step of preparing a BOQ. The work to be carried out is described in detail and a simple language so that the contractor can easily understand what he/she has to do.
2. Quantity Take Oﬀ
Once the work is described, the quantity of work is worked out and taken oﬀ. It gives a detailed idea of amount of work to be performed by a contractor. The quantity of work is given in units like m3, m2, rm, foot, etc.
3. Describing The Rates
The last step in preparing a BOQ is to describe the rates of items of work per units. The rates of each item are worked based on factors like market survey, current rates, schedule of rates (SOR), etc. At last, the total quantity of work is multiplied by the unit rate of the item of work to define the total amount for a particular item of work.
Example OF BOQ
Calculation of materials for RCC Construction:
Let us assume a standard quantity of 1 m3 Cement mortar and a mix proportion of 1:1.5:3. The quantity can be calculated by two methods, i.e Volume method & weight method. We will use the volume method here.
Dry volume of total materials is equivalent to 1.54 times the volume of wet concrete.
Quantity of cement
(1.54×1)/(1+1.5+3) = 0.28 m^3
Since the cement is available in bags and the volume of 1 cement bag is 0.0347 m3.
0.28/0.0347= 8.07 bags of cement
Quantity of sand
(1.5×1.54)/(1+1.5+3) = 0.42 m^(3 ) of sand
Quantity of coarse aggregates
(3×1.54)/(1+1.5+3) = 0.84 m^(3 ) of coarse aggregates
Sometimes an additional contractor’s profit and sundries are included. It generally differs from place to place, organization and work. It ranges from 10 – 20%. In this case, assume 10% of the total cost of materials, labour, and equipment for the contractor’s profit and 7% for sundries.
BOQ of Steel Reinforcement
- Slabs = 1.0% of concrete volume
- Beam = 2 % concrete volume
- Column = 2.5% of concrete volume
- RCC roads = 0.6% concrete volume
Assuming 2.5% as the steel reinforcement required.
2.5/(100×1)×7850 =196.25 kg (Unit weight of steel is 7850 kg/m3)
Estimation of labour for reinforced concrete
The requirement for labour as per the specified quantity of work is as follows:
- Mason – 0.35 day
- Unskilled labour – 3 days
- Water carrier – 1.30 days
- Bar bender, per 100 kg of steel – 1 day
- Mixer operator – 0.0815 day
- Vibrator Operator – 0.0815 day
Cost Of Materials
|Sl. No.||Material||Quantity||Unit||Rate (Rs)||Amount (Rs)|
Cost Of Labour
|Sl. No.||Material||Quantity||Unit||Rate (Rs)||Amount (Rs)|
Cost of materials + Cost of labours = 15780+2460.20 = 18240.20
|Sl. No.||Name Of Items||Quantity||Unit||Amount (Rs)|
|2.||Sundries (Machinery, transport)||7.5||%||1368.5|
Total Cost = Cost of materials + Cost of labours + Additional Cost
= 15780 + 2460.5 + 2918.5 = Rs. 21159
Common Mistakes Made While Preparing Bill Of Quantities.
Some common mistakes made by the quantity surveyor while preparing a BOQ are listed below
- Calculation error in the quantity of work and rates of items of work.
- Inaccurate assumptions of various items of work.
- Incorrect measurement of quantities of work.
- Double counting of items of work.
- Forgetting a specific item of work, which is actually to be counted.
- Including unnecessary items to work.
Advantages Of BOQ
The advantages of BOQ are as follows:
1. A BOQ provides a clear picture of the work to be performed.
2. BOQ helps in managing the construction project with ease, providing the required data necessary for various aspects of project management.
3. It helps in future estimation and cost planning, as a reference for the next project.
Limitations Of BOQ
Disadvantages of BOQ are as follows:
1. If the estimator is inexperienced, the BOQ may mislead the contractors and the clients too.
2. Calculation of quantities of work and its rates shall be done very carefully, else large arithmetic errors may prevail.
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