Construction projects involve many moving parts, from materials and labour to scheduling and budgets. To help manage costs and streamline the bidding process, a bill of quantities is an essential tool for contractors and clients alike.

What Is the Bill of Quantities

The bill of quantities (BoQ) is a type of document in construction project tendering that itemises the quantities of materials, parts, and labour required to complete the scope of work. It provides a detailed breakdown of all elements needed to execute a construction project according to its design and specifications.

The bill of quantities is issued to contractors bidding on the project as part of the tender package. This allows them to accurately price the cost of construction based on the unified quantities. By enabling all contractors to prepare bids referencing the same information, the bill of quantities facilitates a fair, competitive tendering process and consistent cost analysis across different bids.

An accurately prepared bill of quantities is crucial for both the owner of the project and its contractors. For owners, it provides assurance that all aspects of the project are accounted for. For contractors, it allows effective estimation of required resources and costs for executing the work. In the end, the bill of quantities promotes transparency and parity in tendering to obtain the most advantageous pricing and completion of the construction project.

Understanding the Bill of Quantities in Design-Bid-Build Projects

In design-bid-build projects, the bill of quantities is usually included in the bidding package for contractors. Since it already features predefined materials and quantities, contractors have the option to skip their own quantity takeoff and use the BOQ directly for pricing. However, to ensure accuracy and identify any potential gaps in the BOQ, contractors often conduct an independent takeoff, which is the process of analysing architectural and engineering drawings to quantify the materials, labour, and equipment required for a project.

Once contractors complete the BOQ, they submit it to the client for evaluation and selection. In the event of any discrepancies between the contractor’s quantities and the BOQ, contractors can submit a request for information (RFI) for clarification.

When a contractor is chosen, the BOQ becomes the basis for invoicing throughout the project duration, essentially becoming the schedule of values. This enables easy measurement of progress by tracking materials delivered and work completed against the BOQ quantities.

In situations where the design is not fully finalised during the bidding phase, an approximate BOQ serves as a valuable tool to provide initial quantity estimates for pricing. Later on, these amounts can be revised to reflect the final quantities.

Bill of Quantities vs Bill of Materials

The bill of quantities (BOQ) is sometimes mistakenly interchanged with a bill of materials (BOM). However, these documents serve different functions in construction projects.

A bill of quantities is an exhaustive list of all costs, including required materials, labour hours, equipment, and more. It provides a complete estimate for the overall project.

A bill of materials, on the other hand, simply outlines the number of raw materials needed to complete the project (timber, concrete, finishes, etc.). It does not account for labour, equipment, or other costs as a BOQ does.

For large and small projects alike, general contractors may include a BOM in bid packages to assist subcontractors. Like the bill of quantities, the bill of materials enables easier comparison of bids from multiple sub-contractors.

However, it is important to understand that a BOM has a narrower materials-only scope compared to the comprehensive project cost details encompassed in a BOQ. While both aid bidding, these documents serve different bottom-line functions for contractors and owners.

The Purpose of the Bill of Quantities

The bill of quantities serves multiple important functions in the construction process.

First and foremost, it enables standardised and equitable tendering. With all bidders pricing the same specified materials and labour, it is easier to make comparisons. Thus, owners can quickly assess which bids offer the best overall value. On top of that, by creating transparency around scope and pricing, the bill of quantities helps reduce errors and misinterpretations.

Additionally, the bill of quantities allows consultants and quantity surveyors to conduct thorough tender analyses. By evaluating both total costs and individual rates, they can confirm contractors submitted complete, compliant bids that align with specifications and meet budgetary goals. This vetting safeguards owners against improper pricing practices.

Bills of quantities facilitate accurate cost control and projections for owners. With detailed schedules and breakdowns provided upfront, it becomes easier to predict cash flow needs over various cycles of a project. Thus, owners can gain visibility into upcoming expenditures based on the schedules of work.

It can also perform the function of contract administration. Basically, it acts as the basis for the final contract between the client and the contractor. If any disputes or claims arise during construction, it is able to provide a reference point to resolve issues. The documented rates and scopes mitigate confusion and aid conflict resolution.

The comprehensive details within the bill of quantities create an invaluable record of project parameters. This supports maintenance, repairs, and potential expansions down the road. Having these accurate quantities and descriptions on file saves time and effort compared to re-quantifying.

Overall, efficient bills of quantities make tendering more uniform, pricing more precise, and costs more predictable for all parties.

Types of Bills of Quantities

Construction projects may use various types of BoQ. Below, are the most common types:

• Itemised BoQ. It provides a detailed breakdown of all required materials, equipment, and labour, with exact quantities specified for each item. An Itemised BoQ offers the highest level of accuracy.
• Abstract BoQ. Its goal is to summarise total quantities and costs in a condensed format by category rather than detailed items.
• Preliminary BoQ. It is developed early using approximate estimates. The purpose of this bill is to provide a ballpark indication of costs before making final plans.
• Final BoQ. It is the most detailed and precise BoQ created at the end of the design stage as the basis for contractor bidding and project delivery.
• Elemental BoQ. It organises quantities and costs by elements like foundations, walls, doors, etc. rather than traditional trade categories.
• Trade BoQ. This type of BoQ categorises the scope and pricing by trades like electrical, plumbing, framing, masonry, etc. for easy bidding by sub-contractors.
• Location BoQ. It divides the project into zones or areas like 1st floor, 2nd floor, East Wing, etc. as well as quantifies materials and labour by location.

The appropriate BoQ type depends on the project stage, costing needs, procurement approach, and stakeholder preferences. Each offers advantages suited to particular purposes over the construction timeline

Creating an Accurate Bill of Quantities

Producing a precise bill of quantities is a complex process requiring expertise and diligent effort. While the project owner initiates its creation, collaboration is key for the best results.

The design team plays a crucial role in preparing the BoQ as it provides architectural and structural drawings, plans, and material specifications to quantify. Continuous communication ensures every project component is captured at the correct scale and level of detail.

Experienced Quantity Surveyors synthesise this data into a comprehensive documented format. Items are meticulously measured and defined using industry-standard methods. To do so, they usually break the scope of work into smaller pieces, i.e. items, such as individual sections of a building or specific types of work (plumbing, electrical, etc.) In the next step, they determine the quantity for each item as well as its cost based on current market rates. Finally, they calculate the total price of all the materials and labour to assess the final cost of the project.

It is a responsibility of a project owner to supply project parameters, budget goals, and specific needs. Ongoing review of drafts helps align the bill of quantities with owner expectations before finalisation.

It is important that descriptors, measurements, and pricing are accurate. Even small errors can multiply, leading to inflated budgets and problematic bidding. That’s why diligence in every step is critical as it allows for removing assumptions and reflecting realities.

Creating an accurate bill of quantities requires expertise, intense collaboration, precise quantifications, and constant quality control. When done right, it provides a complete cost picture that enabled owners to make informed decisions and manage budgets successfully.

What Does the Bill of Quantities Include? 

A comprehensive bill of quantities is a list that outlines all needed materials and labour over the course of construction. Though formats differ, strong bills of quantities share key components:

• It provides some detail on the project, such as its name, owner, location, as well as the date of BoQ creation.
• Item Numbers. Each entry features a number for easy reference since the list can grow quite long.
• Item Type. Items are categorised as either materials or labour, an important differentiation for measurement and pricing.
• Since there can be many varieties of the same type of item, the bill of quantities usually includes a brief description. For example, an item ‘paint’ can be specified as interior, exterior, etc.
• Unit of Measurement. This component of the BoQ defines units used to measure each item. Materials use counts like gallons, cubic, square, or linear meters, tons, etc., while labour uses time units like hours, per installation, per inspection, etc.
• This section specifies the amount of each material and the time for each labour.
• Unit Cost. It indicates the prices for materials and hourly rates or fees for labour. These numbers factor into total costs.
• Item Total Cost. For each entry, the bill of quantities specifies the total cost by multiplying the unit price by its quantity. All item costs are summed for the grand total budget.
• Terms and conditions. This optional section may include terms and conditions associated with the project, such as warranties, payment terms, etc.

With thorough itemisation, detailed descriptions, and comprehensive cost calculations, the bill of quantities provides a complete financial scope for construction projects. This helps guide purchasing and scheduling while tracking costs. A meticulous bill of quantities is fundamental to construction success.

Who is Responsible for Creating the Bill of Quantities?

The project owner is ultimately responsible for having an accurate bill of quantities to provide to bidding contractors. However, they rarely create it themselves. Although the owner needs the document to get precise bids and submit it to contractors bidding on the project, they typically delegate responsibility for producing the bill of quantities.

This is where PEJA Surveying comes in. With years of experience in construction cost consulting, PEJA Surveying has the expertise to prepare meticulous bills of quantities for all types of building projects. Our team of experienced Quantity Surveyors will work closely with you as a client and your design team to itemise all materials, labour, and equipment costs needed to complete the project.

Leveraging the latest industry-standard software, we compile an organised, easy-to-follow bill of quantities tailored to the project’s specifications. We deliver a level of detail and transparency to give you confidence in the bidding process.

When the Bill of Quantities is Used

Project owners use the bill of quantities at key junctures in the project timeline. Prior to project execution, it makes it possible to accurately estimate total costs. By itemising all materials, equipment, and labour, owners gain insight into projected expenses across various project phases. This helps inform budgeting and financing decisions before commencing construction.

Once a project is approved, the bill of quantities is shared with bidding contractors. It provides them with the detailed information necessary to prepare precise bids for the job. The comprehensiveness of the bill of quantities allows for an equitable, transparent bidding process.

While most useful before breaking ground, a bill of quantities also aids progress tracking during project execution. By comparing the initial quantities to work completed, owners can evaluate advancement and identify any deviations from the original scope.

Benefits of the Bill of Quantities

The bill of quantities helps enhance construction projects in numerous ways:

Accuracy. The meticulous measurement and costing within a BoQ minimise miscalculations that may lead to budget overruns or scope gaps.

• Cost Control. Detailed cost forecasts in the BoQ make it possible to implement proactive monitoring and management of expenditures.
• Clear itemisation provides visibility into what is entailed. As a result, it helps increase the accountability of the parties.
• Streamlined Tendering. Because the bill of quantities provides a detailed list of the materials and works required for the project, contractors have a chance to provide competitive and equitable bids.
• Comprehensive scheduling information presented in the BoQ helps to effectively organise all the processes.
• The BoQ helps reduce misunderstandings and disputes involving the project owner, contractors, and other parties. It is due to providing clear information about project parameters.
• Quality Control. Thorough materials and labour outlining promotes completeness as well as helps reduce omissions and defects.

PEJA Surveying – Your Reputable Consultant Quantity Surveyor

When it comes to selecting a reliable Consultant Quantity Surveyor, PEJA Surveying stands out as a trusted choice. Our team of professionals boasting more than 40 years of combined experience, excels in cost planning, procurement strategies, contract administration, and value management.

With PEJA Surveying as your QS, you can be confident in receiving exceptional cost management support and ensuring the success of your construction project. You can count on us for:

– Feasibility studies and cost advice;

– Cost planning and estimating;

– Value engineering and risk management;

– Procurement and tendering;

– Contract administration and dispute resolution;

– Final account and post-contract services

At PEJA Surveying, we take a client-centred approach, prioritising open communication, collaboration, and delivering cost-effective solutions. Our expertise extends to various sectors, including residential, commercial, industrial, and infrastructure projects. Whether you are a property developer, public agency, or private entity, PEJA Surveying is happy to provide cost management expertise to optimise your project’s financial performance.

So, if you are looking for a professional Quantity Surveyor for your next project, contact us today for a free consultation and quote.