On the third night of a planned six-day shutdown, an inspection identifies additional repair work. The contractor asks to retain a crane and add a shift. The plant team needs a decision before the next handover, but the owner has only a lump-sum request and yesterday’s resource sheet. What exactly is being authorised, and what will it do to the final cost?
This illustrative situation is where shutdown and turnaround cost control earns its place. The owner needs a traceable connection between the work required, the resources deployed, the price basis and the remaining forecast. Waiting for the next monthly report leaves the decision behind.
This guide covers commercial controls for planned plant shutdowns and turnarounds. It is not a shutdown operating procedure. Apply the executed contract, agreed shutdown procedure and their defined approval responsibilities; entitlement and valuation depend on those project documents, not a generic checklist.
Freeze a baseline that the site can actually use
A frozen scope list is useful only if each item connects to an executable workpack. Before mobilisation, reconcile the workpack register with the estimate, contract pricing schedule and shutdown programme.
For each package, identify the equipment or location, document revision, measured quantities, exclusions, pricing basis and responsible team. Distinguish confirmed work from inspection-dependent allowances. An allowance for possible repairs should not quietly become an instruction to perform them.
Check the interfaces that disappear inside broad headings: scaffolding, insulation removal and reinstatement, specialist testing, lifting support, consumables and waste handling. Record whether each sits with the owner, the main contractor or a specialist. The point is to assign the cost once and expose anything still unallocated.
Scope freeze should establish a controlled starting point, not prevent necessary discoveries from being addressed. Record later additions against that baseline, including the reason, authorisation route and affected workpacks. Keep deferred work visible with the authorised technical decision and any future cost consequence.
For the wider package structure, see where quantity surveying supports an oil and gas EPC budget.
Check rates before the resources arrive
Two labour rates with the same hourly figure may cover different costs. One may include supervision and small tools; another may exclude both. Resolve these differences before a busy night shift turns them into a disputed invoice.
Build a short commercial reference from the actual contract. It should answer:
- Which labour categories, equipment types and units apply?
- What do normal-time, overtime and shift rates include?
- When can standby, minimum hire or mobilisation charges apply?
- Are supervision, consumables and subcontract mark-ups included or separately recoverable?
- Who can authorise daywork, verify records and approve valuation?
For daywork, connect each resource entry to a workpack, date, shift and instruction reference. Check quantities of resources as well as rates: duplicate personnel entries, overlapping equipment allocations and inconsistent hire periods deserve explanation.
A signed sheet may confirm an observed resource record without resolving every commercial issue. Its effect depends on the contract, the document wording and the signer’s authority. Make those distinctions explicit before execution; do not invent them after a disagreement.
In the opening example, the owner should see why the crane is still needed, the proposed retention period, the applicable charging basis and who is authorised to decide. A daily resource total alone cannot answer those questions.
Capture evidence while the shift is still fresh
At handover, “mechanical work 80% complete” is too vague to price a change or forecast tomorrow’s resources. Agree workpack-level progress rules before the shutdown. Use quantities or defined completion stages that the site team can verify consistently.
The U.S. Department of Energy’s earned value guidance links scope accomplishment with cost and schedule. Applied here, the useful principle is to compare evidence of completed work with the same baseline used to plan and price it. That does not require treating every small shutdown as a full formal earned value system.
Keep a compact shift record covering completed quantities, inspection status, resources used, restrictions encountered and unresolved instructions. Reference photographs and technical records where permitted by site rules. Name the recorder and verifier, and carry unresolved items into the next handover.
Separate work reported complete, technical acceptance and value eligible for payment. They can differ. A repair awaiting required inspection is not automatically in the same position as an accepted workpack, and neither status alone determines the amount payable.
For the contractual payment assessment, use our guide to how quantity surveyors value construction progress claims. During a turnaround, the additional discipline is capturing the evidence before crews rotate or equipment leaves.
Make urgent changes visible without bypassing safety
An inspection finding can create a technical decision, a schedule decision and a commercial decision at once. Give them a shared event reference, but do not treat one approval as a substitute for the others.
The UK Health and Safety Executive’s permit-to-work guidance highlights responsible authorisation, communication and formal handback for hazardous maintenance. Commercial approval does not provide that safety authorisation. Follow the site’s safe-work and emergency arrangements; a cost-control process must not obstruct necessary protective action.
For a proposed addition, record the discovery, why the baseline does not cover it, the technical disposition, affected workpacks, initial cost range and possible schedule effect. Identify the contractual notice or instruction route and the person authorised to act. Use the project’s agreed expedited process where one exists.
Keep the initial estimate separate from the final measured value. If an authorised instruction carries a spending limit or requires further approval, track that condition through each shift. Do not assume that approval of extra work also approves every claimed resource, delay or acceleration cost.
For a delay-related claim, preserve the event timeline, affected activities, available work fronts and actual resource records. The planner should assess schedule effects; the commercial team should assess the contractual and valuation basis. A stopped activity does not, by itself, establish the claimed effect on shutdown completion.
Use the same status discipline as our variation order control guide: submitted, under review and agreed values must remain distinguishable.
Refresh the cost to finish, not just the spend
A low invoice total on day four can conceal two shifts of unprocessed labour, retained equipment and an unresolved repair package. Agree a reporting cut-off with finance, procurement and the site team so the owner sees one reconciled position.
At each agreed review, show incurred cost, including the agreed accrual for work performed but not yet invoiced, remaining committed cost, additional uncommitted work still required and assessed exposure not covered elsewhere. Reconcile overlaps: a cost already accrued must not reappear as wholly unspent purchase-order value.
Keep the forecast linked to the latest workpack plan. If an extra shift is proposed, show the incremental resource cost and the schedule assumption being tested. Any claimed benefit from avoiding production downtime needs a separately agreed operational and financial basis; it is not automatically an offset against contractor cost.
The GAO Cost Estimating and Assessment Guide supports explicit assumptions, risk analysis and updating estimates with actual costs. For a shutdown, apply that discipline to inspection uncertainty, remaining work and resource duration rather than relying on an unexplained percentage allowance.
Track contingency against the risks it covers and the authority required to release it. When a risk becomes an assessed repair cost, reconcile the allowance so the same exposure is not counted twice. Remaining contingency is not permission to add unrelated scope.
Close the commercial facts before the team disperses
Plant restart and commercial closeout are different milestones. Before demobilisation, identify what evidence would become difficult to recover once the supervisor, specialist crew or hire equipment has left.
Reconcile final workpack quantities, resource records, equipment off-hire dates, material returns and outstanding instructions. Connect each open change or claim to its supporting documents and current assessment. Record what is agreed, what is disputed and what is still missing.
Assign each unresolved item an owner and a target date consistent with the contract. Keep technical handover, payment assessment and final-account agreement separate. Do not label the account closed merely because the plant is operating, or impose a generic settlement deadline that the contract does not contain.
Finish with a short cost bridge: original baseline, authorised scope movement, quantity or rate movement, assessed outstanding exposure and forecast or agreed final cost. Retain enough context to make the next shutdown estimate useful. A headline cost per workpack means little if the previous event included different access constraints or inspection findings.
Frequently asked questions
Does scope freeze mean no additional shutdown work can be approved?
No. Scope freeze establishes the baseline against which later discoveries and additions are controlled. Necessary work follows the site’s technical and safety processes, while its authorisation, notice and valuation follow the executed contract and agreed shutdown procedure.
Does signing a daywork sheet automatically approve payment?
Not necessarily. The effect depends on the contract, the sheet’s wording and the signer’s authority. Resource verification, approval to perform work and agreement of the amount payable may be separate actions. Define those responsibilities before the shutdown begins.
How much contingency should a turnaround carry?
There is no universal percentage. Assess the remaining scope uncertainty, inspection-dependent work, execution risks and available evidence. Record the allowance’s basis and release authority, then reconcile it as risks are resolved or become forecast costs.
Set up the decision trail before the next shutdown
Start with one representative workpack. Can the owner trace its quantity, rate, progress evidence, change status and cost to finish without reconciling several conflicting files? If not, resolve that gap before mobilisation.
Discuss your shutdown’s quantity surveying and commercial-control requirements with GEMS. Bring the scope register, pricing schedule, shutdown programme and reporting requirements so the proposed support can be defined around the decisions your team needs to make.
