Item number (could be a serial number or part number) Description Unit of measurement Quantity Rate per unit (to be filled in by contractors bidding on the project) Total cost of material (to be filled in by contractors bidding on the project)
The name and specifications for each material go into the “description” column of your BOQ spreadsheet. For example, if you’re building a house, you might need framing materials, sheetrock, bricks, concrete, flooring materials, wiring, lighting fixtures, and kitchen and bathroom fixtures. Be as specific as possible with your description. Include the dimensions of the surface or area, the thickness of the material you need, and any other details that might impact the quality of the material.
For example, if you’re building a house, you might have separate categories for framing, electrical, plumbing, and flooring. Since both framing and flooring require nails, each of these categories would have a row for “nails” under each category. Traditionally, each row is numbered consecutively from “1,” with the numbers starting over for each category or section.
For example, if part of your project includes painting a room, you might list “gallon” as the unit of measurement for the paint, then “10” as the number of gallons of paint you need. Add 15-20% to each material calculation to account for waste. Sometimes your unit of measurement will reflect how that particular material is sold. For example, if cable is one of your materials, and that cable is sold in spools of a standard size, you could use “spool” as your unit of measurement.
For example, if a brick wall is part of your project, you would need to know how many bricks the average bricklayer can lay in one hour—that would be your man-hour, roughly, although it would also need to account for other aspects of bricklaying, such as mixing mortar. Different contractors may work with different crew sizes. Your total number of man-hours helps contractors figure out what size crew they need for the job. Based on the number of bricks you need for your brick wall, it might take 200 man-hours for the build. But for a team of 5 bricklayers could get it done in 40 hours—so maybe a week to 10 days. On top of your basic man-hours include time for rest breaks and meals. This is still a very conservative estimate because you can’t account for things that might happen once work starts. Talk to contractors to get an idea of how long it would take to complete a given task. A quantity surveyor would usually be able to estimate this off the top of their head, based on their experience with similar projects.
Your initial cost estimate gives you a benchmark that helps you rate the feasibility of the bids you get in. Don’t include these numbers in the BOQs you give to contractors—just keep it for your own reference. It might not be strictly necessary to make an initial cost estimate for every project, but they can actually save you a lot of time on larger projects where you have a lot of bids to sort through.
For example, if you’ve estimated it will take a total of 1,000 man-hours to build your house, it would take 25 hours for contractors to complete the build (assuming they all work 40 hours a week with no delays). You might set a schedule for 30-40 weeks.
If you have experience managing a building project, you can save some money by overseeing the project yourself. Otherwise, you’ll likely want to hire a main contractor to manage and supervise the project. Always verify the contractors’ licenses and check their references before you solicit bids from them. Ask your architect or quantity surveyor for contractor recommendations. They tend to know people in the industry and can tell you who you should talk to (and who you should stay away from).
This is where your initial cost estimate comes in handy. If a contractor submits a bid significantly lower than your initial cost estimate, you know to be skeptical.
For example, what if there’s a shortage of a particular material you need to complete the flooring? Looking at your BOQ, you could push ahead with another part of the project that isn’t dependent on flooring so your project stays on schedule.
