Note
Stage Billing After Programme Revision
When a subcontract is signed, the billing stage definitions are written against the programme that exists on day one. Stage 2 might be defined as “installation complete on levels 4 and 5.” That definition made sense when the main contractor’s programme showed civil handover of those floors in week six.
Then the programme changes. Civil on levels 4 and 5 slips to week twelve because the structural frame ran late. Your team is ready but cannot touch those floors. Meanwhile you complete level 3, which no existing billing stage covers. The stage that triggers on work you can actually do has no billing milestone attached to it.
This situation is not unusual. It is the normal state of most Thai construction projects after the first month. The problem is that billing stage definitions in subcontracts are written against a specific programme. They do not update automatically when the main contractor revises the schedule.
Why Does a Programme Change Create a Billing Gap?
When the work sequence shifts, two problems arise at once.
First, completed work falls outside every billing trigger. Your level 3 installation is done. No stage pays on level 3 completion because stage 2 was written for levels 4 and 5. Labor, materials, and supplier invoices sit ahead of any billing right.
Second, the stage you cannot yet reach keeps accumulating. Stage 2 remains unearnable not because of your team’s work, but because the main contractor has not handed over the floors that stage 2 names. Every week that continues, the gap between your cost outflow and your billing inflow widens.
When Is the Right Time to Request a Stage Amendment?
The right moment is the first week a programme revision becomes visible.
In practice, a main contractor issues a revised programme as a formal update submitted to the owner or circulated to all subcontractors. The moment you receive that document, compare it against your stage definitions and identify which milestones have been displaced.
A stage amendment is easier to negotiate before significant cost has accumulated. Once a three-month gap has built up, the conversation shifts from a clean administrative update to an argument about who bears the cost of the revision. The written request also documents the date the misalignment was identified, which matters if the gap becomes part of a claim later.
How Do You Frame the Amendment Request?
A well-constructed stage amendment request has three parts.
The first is what changed. State the original stage definition and the specific revision to the main contractor’s programme that displaced it. The revision is not in dispute because the main contractor issued it.
The second is what work has actually been completed. Name the scope, the floors or zones finished, and the date completion was reached. This is not a request to pay for work that has not happened. It is a request to recognise work that has already met the original quality and scope requirements for that portion of the contract.
The third is the proposed replacement definition. Options include replacing a floor reference with a measurable unit count across any floor, adding a progress milestone for scope completed out of sequence, or replacing fixed floor references with a handover-linked trigger that follows the main contractor’s actual access schedule.
Worked Example: Partition Work Across Seven Floors
A partitioning subcontractor’s contract defines three stages: Stage 1 on completion of floors 1 and 2, Stage 2 on completion of floors 3 and 4, Stage 3 on completion of floors 5 through 7 with snagging accepted by the main contractor.
The main contractor issues a programme revision in week five. Civil handover of floors 1 and 2 is delayed four weeks because MEP rough-in on those floors ran over. Floors 3 and 4 are available because a separate civil team had worked the upper floors first, ahead of schedule.
The partitioning subcontractor completes floors 3 and 4 by the end of week six. Stage 1 is blocked by the delay to floors 1 and 2. Stage 2 is defined for floors 3 and 4 but cannot be billed until stage 1 has settled under the sequential payment terms. No existing stage pays on the work that is actually done.
A written programme-change notice goes to the main contractor’s project manager in week six, identifying the displacement and proposing a provisional stage for floors 3 and 4 as completed out of sequence, set at the same value as the original stage 2 scope. The amendment is agreed in writing in week eight, and the invoice is submitted immediately after sign-off.
Without the amendment, floors 3 and 4 would sit completed and unbilled until floors 1 and 2 were finished and stage 1 could settle, adding at minimum six weeks of carrying cost on work that had already been accepted.
Does a Stage Amendment Affect LAD Exposure?
A billing stage amendment changes when you can invoice for completed work. It does not change the overall contract completion date or your LAD exposure under the original terms, unless the amendment also modifies the completion milestone.
Stage definitions and overall completion dates are separate contract clauses. A billing stage amendment addresses when invoicing is permitted for scope already completed. It does not extend the time by which all work must be finished. If your written request records the programme revision and its effect on your access, the same documentation can support a delay analysis if the main contractor later asserts LAD for a completion date that the revision itself caused to slip.
Can I invoice for a floor not mentioned in any billing stage?
Not under the original contract terms without a written agreement from the main contractor. Stage definitions are contractual rights, not estimates. An informal understanding may not hold when the main contractor’s accounts team processes the application against the original stage schedule. The written amendment is what creates the billing right that the payment application can reference.
What if the main contractor refuses to amend the stage definitions?
A refusal does not eliminate the cash flow gap, but it establishes the record. Documenting the programme revision, your completion of work outside any existing billing stage, and the request that was refused is the foundation for a formal claim. The documentation you build now is the substance of whatever dispute process the contract provides.
How do I know when a programme revision is formal enough to act on?
A main contractor-issued revision to the master programme, submitted to the owner or circulated to all subcontractors in writing, is a formal revision. A verbal suggestion at a site meeting that the sequence might change is not. Wait for the written programme update before linking your amendment request to it. The written revision is what your request references and what supports the amendment if it is later disputed.
If your billing stage definitions are currently pointing at floors or milestones that the main contractor’s revised programme has moved out of reach, a 45-minute call is a useful place to start. We look at your stage definitions, the current programme position, and the work that falls outside any existing billing trigger.