Understanding Bill of Quantities in Construction
Contents |
[edit] Introduction
When it comes to complicated large-scale construction projects, contractors find it difficult to compare several proposals. Before comparing prices, they need to verify various bids and the scope of work. To help construction owners with the bidding process, a bill of quantities (BOQ) can be used to streamline bids and make sure they are consistent. This happens because the work and quantities need to be priced before the project is sent to bid. It takes the guesswork out of the bidding and helps to analyse bids efficiently.
[edit] What does “Bill of Quantities” Exactly Mean?
A bill of quantities (BOQ or BQ) is typically used on larger construction projects. It consists of a list of materials and services needed to perform a task. The list comprises labour, materials, and quantities of each and is often framed by the architect or engineer after the project design is finished.
Once prepared, the BOQ is issued to contractors to provide pricing for the works. It allows contractors to focus on pricing instead of managing project takeoffs. After this process, the pricing is shared with the client for inspection and contractor selection.
When a contractor is selected, the bill of quantities can be used to create invoices for the project. The same form is used, and project progress is easy to estimate based on the amount of material on the job site and the work completed.
[edit] What is the purpose of the Bill of Quantities?
Bills of quantities allow for quick comparison of contractor bids. As everyone is quoting the same amount of work, discrepancies in pricing are easy to spot. This gives clients confidence that the proposal consists of all the work in the tender documents and that they are attaining the best price.
Since quantities and amounts are offered, there’s no room for misconceptions and less chance of mathematical blunders. This helps ensure that the bid price is precise. It also helps construction project owners with cost management and cost forecasts. Depending on the project schedule and the breakdown on the BOQ, the client can predict the amount of work that will be accomplished in each billing cycle. This allows them to estimate their cash flow needs as the project advances.
[edit] How do you prepare the Bill of Quantities?
Simply break down the work into items that can be quantified or calculated. This breakdown is often based on a traditional work breakdown structures, like CSI codes.
The list of work items comprises the quantity of material, a short description, and the unit of measure. Hence, the contractor sets prices for the work listed on the bill of quantities based on the drawings and specifications provided.
The general contractor sends the cost back to the client for review, where their proposal is compared to other bidders.
Once a contract is appointed, the bill of quantities can be used to create payment applications as the work advances. The contractor notes the completed monthly charges on the form and multiplies them by the cost for each item to get the invoice amount.
Although engineers and architects usually form the bill of quantities for a project, more businesses are using cloud-based software to draft their list of quantities. This software creates the list and can revise it quickly if the model is updated.
[edit] Why is the bill of quantities crucial?
The bill of quantities is one of the most critical documents in the construction industry. Here are a few reasons why:
- It's an Evaluation & Comparison Opportunity: The evaluation can be detailed as the elements of all the items are adequately described. Also, it helps compare each contractor based on the items to accomplish a fair deal.
- Detecting Prospective Problems: The attribute level means that it is likely to see potential problems and plan to eradicate or mitigate them.
- Better Project Planning: Because items and quantities are documented, the project planner only has to specify the duration of work and organize the resources.
- Restricts Timeframes: Get your materials organized on time since professionals know the material quantities.
[edit] Related articles on Designing Buildings
- Advantages of a bill of quantities
- All-in rates
- Approximate bill of quantities
- Approximate quantities.
- Bill of materials.
- Bill of quantities.
- Bill of quantities breakdown structures BQBS
- Bill of quantities software
- Bill of quantities v Schedule of rates.
- Bill.
- Common mistakes in bill of quantities
- How to take off construction works
- New Rules of Measurement
- Priced bill of quantities
- Standard Method of Measurement SMM7
- Taking off construction works
- Types of bill of quantities
- Unpriced bill.
- Without quantities.
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