What is the difference between Bill of Materials vs Bill of Quantities
The bill of materials (BOM) refers to the hierarchical list of construction raw materials, which is required for the manufacturing or assembling of the construction product. The BOM helps to provide detailed information regarding each and every item used in the construction project, its quantities and its assembly information, thus helping to streamline the production procedures, as well as minimising the risks of errors in the manufacturing process.
Key components of the bill of materials (BOM)
Part number
The BOM provide a unique identifier for each and every part or item used in the construction project.
Description
The BOM provide a detailed description of the construction item along with its specifications and characteristics.
Quantity
The required quantity of each item used in the construction and manufacturing process has been provided by the BOM.
Measurement unit
The BOM provides the unit in which the quantities of each item have been measured.
Reference designators
The specific reference point or location has been provided in which each construction item has been installed.
Sub-assembiles
The BOM also provides the breakdown of sub-assemblies and their respective components.
Hierarchy
A structured hierarchy has been provided by the BOM, which helps to represent the relationship among the different levels of the construction components and sub-assemblies.
Concept about bill of quantities (BOQ)
The bill of quantities (BOQ) helps to outline the construction materials, the number of labourers and the estimated unit costs for the construction project. Thus, the bill of quantities is involved in the accurate cost estimation process, project budget tracking process and transparent tendering process. The bill of quantities (BOQ) has often been structured on the basis of the work packages or trade sections, for example, plumbing, masonry and electrical.
Key components of the bill of quantities (BOQ)
Description of the item
The BOQ provides a clear and concise description of each and every item involved in the construction project.
Unit measurement
The BOQ also provide specific units, for example, kilograms, meters, or hours for measuring the quantities of each item involved in the construction project.
Rate
The BOQ also provide the unit price or unit cost as per the quantity of each item.
Quantity of each item
The BOQ also provides the estimated or measured quantity of the item that is required for the construction project.
Calculated amount
The BOQ also provide the calculated cost for each and every item used in the construction project.
Summary
In the BOQ, an overall summary of the cost and quantities for each trade has been provided along with the applicable taxes or contingencies.
Key differences between the bill of materials (BOM) and the bill of quantities (BOQ)
Based on the purposes
The BOM has been used for the management of the inventories, procurement procedure and also used in the production process of the construction items. On the other hand, the BOQ is involved in the budgeting of the construction project, the cost control process of the project and also involved in the project bidding process.
Based on the scope of information
BOM focuses on the manufacturing of construction materials, whereas the BOQ focuses on both construction materials and labourers for the construction project.
Based on the timing
The BOM has been prepared later on the construction project in the meantime of the detailed design phase, whereas the BOQ has been prepared during the pre-construction phase.
Based on the level of detail
Detailed material specification has been provided by the BOM, whereas a higher-level overview has been provided by the BOQ, which helps to focus on the quantities and costs of the construction materials that are required for the construction project.
Based on the applications
The BOM has been widely used in the manufacturing and production environments throughout the different industries, for example, the electronics industry, the consumer goods sector, the automotive industry and the pharmaceutical industry.
Whereas, the BOQ has been used by the contractor and suppliers for preparing accurate bids and quotations for the construction project. The BOM helps to encompass all the construction components and materials, which are required for assembling or producing a finished product, whereas the BOQ plays an important role in the tendering process by providing detailed information regarding the construction project.
To learn more, watch the following video tutorial.
Video Source: FF Granary
The BOM provide a clear roadmap of the construction components and ensures the presence of all necessary parts of the construction project. On the other hand, the BOQ helps to guide the procurement team about the essential materials required in the construction project.
