In this article we cover:
- What a Schedule of Works is and when it is used
- What a Bill of Quantities is and how it differs from a Schedule of Works
- Why a BOQ can help you compare contractor quotes more fairly
- How these documents can help control costs and avoid misunderstandings
- Practical tips for self-builders before going out to tender
If you’re about to begin a self-build project, you’ll soon come across a range of technical documents.
Two of the most important are the Schedule of Works and the Bill of Quantities (BOQ). Understanding what these are – and how they differ from one another – can help you manage procurement, costs and project oversight more confidently.
What is a Schedule of Works?
A Schedule of Works is a detailed list of all the work elements required for your project. Think of it as a comprehensive checklist outlining what needs to be done:
- For new builds, the schedule often references the drawings since items on them are clearly shown and ‘new.’
- For refurbishments or renovations, the schedule is typically longer and more specific. For example, it might specify “remove existing staircase and widen opening,” spelling out each individual alteration.
Its purpose is to provide a clear, itemised description of all the works required. This makes it a useful document when you are communicating with contractors, designers, and surveyors – making sure everyone has a shared understanding of the project requirements. It can also be used as a project management tool, helping to track progress through each stage of construction.
What is a Bill of Quantities (BOQ)?
While a Schedule of Works tells you ‘what needs doing,’ a Bill of Quantities goes much further, adding detail and measurement to each item.
The BOQ lists every element defined in the Schedule of Works, but includes specific quantities and sometimes rates for each item.
For example: Instead of just saying “tile the floor,” the BOQ would note “tile the floor with 600x600mm tiles, allow for 10 square metres.”
This helps make sure that each part of the work can be priced properly when you are asking for quotes. It acts like a shopping list that can be sent to different contractors or suppliers, so everyone is pricing the same things. This makes it much easier to compare quotes, because you can see who is offering what and avoid comparing completely different versions of the job.
These documents are useful because they make the job clearer for everyone involved. When contractors are pricing the work, they can see exactly what is included, which helps avoid confusion or missed items.
They also help keep costs under control. A well-prepared Bill of Quantities, especially with input from a Quantity Surveyor, gives you a much clearer way to compare the actual spend against the original budget.
They make it much easier to compare quotes fairly too. If each contractor is pricing the same list of work, you can see more clearly where the costs differ and reduce the risk of hidden extras or misunderstandings about the scope.
They are also helpful once the project is underway. Both the Schedule of Works and the Bill of Quantities can be used as practical checklists to track progress, spot changes, and manage any variations as the work moves along.
Tips for self-builders
- Get a Quantity Surveyor (QS) involved: Ask a QS to prepare a detailed BOQ before you ask contractors for prices. This helps make sure nothing important is missed.
- Ask for full pricing: Get your QS to add typical costs to each item in the BOQ. This gives you a useful benchmark when the contractors’ quotes come back.
- Keep it up to date: As the design or project details change, make sure the BOQ and Schedule of Works are updated too.
- Use it to track changes: If the scope, materials or labour change during the build, update the documents so you can keep an eye on extra costs or possible savings.
Jack Hounsham, Appledown Projects, appledownprojects.co.uk
