Construction Preliminaries: What They Include and How to Price Them in a BOQ

Construction preliminaries are the costs of setting up, managing, supporting, and closing a project. They may not become part of the finished building, but they are essential to delivering the measured works safely, legally, and on schedule. A weak preliminaries allowance can leave a contractor exposed to losses, while an inflated or poorly described allowance can make a tender difficult to compare.

A reliable estimate should connect each allowance to the project scope, programme, site conditions, and contract obligations. Digital construction estimating software for accurate BOQs can also help teams coordinate documents, responsibilities, records, and cost information, but the underlying pricing logic still needs to be prepared carefully. This guide explains what construction preliminaries include and how to price them in a bill of quantities (BOQ).

What are construction preliminaries?

Construction preliminaries are the resources, services, temporary facilities, and project-specific obligations required to execute the permanent works. They commonly include site establishment, supervision, welfare, security, temporary utilities, health and safety controls, testing, insurance, and handover activities.

Preliminaries are not normally the same as measured construction work. For example, concrete in a foundation is a measured work item, whereas the site office used by the team managing that foundation is usually a preliminary. The exact treatment depends on the specification, measurement rules, and contract conditions, so the BOQ should state what is included and what is excluded.

Preliminaries should also be distinguished from:

• Direct work costs: Labour, materials, plant, and subcontractor costs directly attributable to a measured activity.
• Corporate overheads: General business costs that support multiple projects, such as head-office administration.
• Profit: The contractor’s commercial return, usually added separately from project preliminaries.
• Provisional sums: Allowances for work that cannot be sufficiently defined when the BOQ is prepared.

What do construction preliminaries include?

Mobilization, demobilization, and site establishment

Mobilization covers the initial resources needed to start work. Depending on the project, it may include transporting equipment, bringing site staff to the project, installing temporary fencing, preparing access points, establishing storage areas, and arranging temporary power and water.

Demobilization is the reverse process at completion. It can include removing cabins and temporary services, clearing surplus materials, dismantling temporary protection, transporting plant away, repairing temporary access, and leaving the site in the condition required by the employer.

Site offices, storage, utilities, and welfare facilities

Site facilities may include offices, meeting rooms, document-control areas, storage containers, workshops, toilets, washing facilities, changing rooms, drying rooms, canteens, drinking water, temporary lighting, and power distribution. Pricing should account for the number of workers, project duration, site constraints, and the level of facilities required by the contract or local regulations.

Temporary utilities should not be treated as a single unexplained allowance. Consider connection charges, generators or temporary electrical systems, fuel, water tanks, drainage, internet, communications, metering, maintenance, and final disconnection. If the employer provides a service, the BOQ should clearly identify the contractor’s remaining responsibility.

Management, supervision, and administration

Time-related staff costs are often one of the largest parts of preliminaries. The allowance may cover the project manager, construction manager, site engineers, forepersons, quantity surveyors, planners, document controllers, administrative staff, and dedicated health and safety or quality personnel.

Estimate these costs against the programme rather than applying an arbitrary percentage. A long project, phased handover, restricted working hours, or multiple work fronts may require additional personnel. Include salaries, employment costs, travel, accommodation where applicable, communications, and reasonable relief or replacement arrangements.

Temporary works, access, protection, and logistics

Temporary works are arrangements needed to support construction but not intended to remain as part of the completed asset. Examples include temporary roads, working platforms, ramps, propping, hoarding, scaffolding used for general access, edge protection, temporary drainage, traffic management, lifting zones, and weather protection.

Do not assume that every temporary work belongs in preliminaries. Some items are directly associated with a particular measured activity and may be priced within that trade. The key is to avoid both omissions and double counting. Review the method statements, drawings, specifications, site logistics plan, and subcontractor scopes together.

Health, safety, security, environmental controls, and quality management

Preliminaries may include site security personnel, gates, access control, alarms, cameras, lighting, signage, barriers, visitor systems, and protection of materials. Safety costs can include induction systems, personal protective equipment for general use, first-aid facilities, emergency arrangements, training, inspections, and safety supervision.

Environmental and quality obligations may require dust suppression, wheel washing, waste segregation, noise monitoring, spill response, environmental inspections, sample storage, quality records, and test coordination. Include recurring costs for maintenance and consumables instead of pricing only the initial installation.

Permits, surveys, testing, insurance, bonds, and compliance

Depending on the contract, preliminaries can include building permits, road-opening permits, temporary-works approvals, utility coordination, setting-out support, condition surveys, laboratory testing, inspections, insurance premiums, performance bonds, advance-payment guarantees, and statutory fees.

Responsibility is especially important here. A permit may be obtained by the contractor but paid for by the employer, or it may be included in a separate provisional sum. Read the preliminaries specification and contract amendments rather than assuming that every compliance cost belongs to one party.

Handover, commissioning, records, and closeout

Closeout costs are frequently underestimated because they occur after most physical work is complete. Allow for as-built information, operation and maintenance manuals, training, demonstrations, commissioning support, statutory certificates, test records, spare parts, cleaning, snagging, defect inspections, final surveys, waste removal, and the return of temporary facilities.

If the contract includes a defects or maintenance period, clarify which staff, inspections, security arrangements, and temporary services continue after practical completion. These costs should not disappear from the estimate simply because the main construction programme has ended.

How are preliminaries organized in a BOQ?

A practical BOQ often separates preliminaries into fixed, time-related, and project-specific items. Names vary between measurement systems and forms of contract, but the underlying principle is useful: fixed costs occur once, time-related costs vary with duration, and other items cover defined obligations that do not fit neatly into either group.

Some contracts use a single preliminaries section, while others require separate items for each obligation. A detailed breakdown improves tender comparison and makes changes easier to value. It also shows the client which costs are sensitive to a programme extension.

How to price construction preliminaries step by step

1. Review every contract source

Start with the drawings, specifications, employer’s requirements, programme, site information, geotechnical reports, logistics constraints, contract conditions, and amendments. Highlight words such as “provide,” “maintain,” “remove,” “obtain,” “submit,” “protect,” and “test.” These obligations often reveal preliminary costs that are not obvious from the drawings.

2. Establish the working duration and sequence

Identify the planned start date, completion date, sectional handovers, commissioning period, anticipated delays, and any seasonal or restricted working conditions. Then map the site resources to the programme. A security guard required for the full project is a time-related cost; a temporary gate installed once is normally a fixed cost.

3. Create a preliminaries responsibility matrix

List each requirement and identify whether it is provided by the employer, main contractor, subcontractor, utility provider, or another party. Record the pricing location, responsibility, duration, and assumptions. This simple matrix helps prevent omissions and double counting, particularly where subcontractors price their own access equipment, supervision, testing, or welfare.

4. Build resource and cost schedules

For staff, prepare a role-by-role schedule showing the number of people, start and finish dates, and cost per period. For facilities and equipment, list hire, delivery, installation, operation, maintenance, fuel, removal, and reinstatement. For one-off items, obtain supplier or subcontractor quotations where the cost is material or highly site-specific.

5. Separate fixed and time-related costs

Do not hide every cost in one lump sum. Separating fixed and time-related items makes the estimate more transparent and provides a logical basis for valuing extensions of time. It also allows the estimator to test how a shorter or longer programme affects the tender total.

6. Check interfaces with measured work

Review each trade package for shared site resources and exclusions. Confirm whether scaffolding, temporary protection, testing, access plant, hoisting, waste removal, and supervision are included in the trade price or the main preliminaries. Ask subcontractors to state their assumptions so that the main estimate can be reconciled.

7. Apply realistic allowances and document assumptions

Use supplier quotations, current internal cost data, hire schedules, labour rates, and the project programme. Where information is incomplete, record the assumption and explain the potential commercial impact. A transparent allowance is more useful than a precise-looking figure that cannot be supported.

Example BOQ structure for preliminaries

The following is an illustrative structure, not a universal rate schedule. Quantities and units should be adapted to the project and the applicable measurement rules.

Common pricing mistakes to avoid

• Using a blanket percentage without a build-up: A percentage may be useful as a reasonableness check, but it should not replace a project-specific estimate.
• Ignoring the programme: Monthly staff, cabins, security, utilities, and plant costs can change significantly when the duration changes.
• Missing closeout obligations: Handover documents, testing, training, cleaning, and demobilization need explicit allowances.
• Double counting subcontractor costs: Confirm whether specialist contractors have included their own supervision, access, welfare, testing, and protection.
• Failing to price site constraints: Restricted access, occupied premises, phased work, night shifts, remote locations, and limited storage can increase preliminaries.
• Leaving assumptions undocumented: Unclear assumptions make tender comparisons and variation assessments harder.
• Mixing risk and preliminaries: Defined project support costs should not be confused with general contingency or contractor profit.

How to review and improve a preliminaries allowance

Before finalizing the BOQ, compare the preliminaries schedule with the programme and logistics plan line by line. Ask whether every recurring resource has a start and finish date, whether fixed items have a measurable basis, and whether the scope includes removal as well as installation.

Run at least three checks. First, compare the total against similar internal projects while accounting for differences in scale and complexity. Second, test the effect of a programme extension on time-related costs. Third, reconcile the schedule with subcontractor quotations and the risk register. These checks do not create a universal “correct” percentage; they reveal omissions, inconsistencies, and unsupported assumptions.

FAQ about construction preliminaries

Are preliminaries included in the construction cost?

Usually, yes. They are part of the contractor’s cost of delivering the project, although the BOQ may show them separately from measured work, overheads, and profit.

Are preliminaries the same as overheads?

No. Preliminaries are generally project-specific costs, while overheads often refer to broader business costs. Contract definitions vary, so the pricing documents should state the intended treatment.

Should preliminaries be priced as a percentage?

A percentage can provide a preliminary check, but a detailed build-up is safer. The correct allowance depends on duration, site conditions, scope, logistics, staffing, compliance duties, and the required facilities.

How are time-related preliminaries valued during a delay?

Where the contract permits recovery, the valuation normally considers demonstrable additional project costs caused by the delay, such as site staff, facilities, security, and temporary services. The contract’s notice, records, and valuation provisions must be followed.

Who prepares the preliminaries section of a BOQ?

A quantity surveyor or cost consultant commonly prepares the BOQ, often with input from the design team, contractor, planner, and project manager. The contractor should still review the section carefully because its construction method and programme affect the actual cost.

Conclusion

Construction preliminaries provide the infrastructure and management framework that allows permanent works to proceed. A dependable BOQ identifies each obligation, assigns responsibility, separates fixed and time-related costs, connects allowances to the programme, and documents the assumptions behind every significant item.

Before issuing or pricing a tender, check mobilization, facilities, supervision, temporary works, safety, security, environmental controls, testing, insurance, permits, utilities, demobilization, and handover. This disciplined approach gives project stakeholders a clearer estimate and gives contractors a stronger basis for managing cost and change.

For a project-specific review, Vision Constructors can help teams examine preliminaries schedules, clarify scope responsibilities, and improve the cost basis used for tendering and commercial control.