Note
Off-site Fabrication Payment Stages
Shop-fabrication trades face a cash flow problem that site-only contractors do not. By the time the steel panels reach floor 10, the cutting, welding, and finishing happened two or three months earlier. Labour and materials have been paid. The only thing missing is a billing stage that recognises any of that work.
Most Thai subcontracts do not provide one. The standard billing schedule is written around on-site milestones: “structural frame complete,” “50 percent of cladding installed,” “final fix complete.” The fabrication shop might as well not exist. If you are a metalwork contractor, a joinery house, a curtain-wall fabricator, or any trade that completes a significant share of its value away from site, the gap between spending money and issuing a billing stage is the core cash flow problem in your business.
Why On-site Billing Stages Miss the Shop Entirely
A billing stage in a Thai subcontract is typically tied to physical conditions at the job address. Stage 2 triggers when a specified percentage of the zone is complete on site. Stage 3 triggers when the next zone hands over. The logic works for trades that build sequentially on site. It breaks for trades that fabricate in batches, deliver, and install over a compressed window.
A contractor producing aluminum cladding panels for a 20-storey building might spend five months cutting, anodizing, and quality-checking panels before a single one touches the building. Under a standard on-site billing schedule, nothing gets billed until installation begins. Under a contract with an off-site payment clause, there is a stage tied to “90 percent of panels fabricated and ready for delivery,” certifiable at the shop, months before the panels leave the warehouse.
What Does an Off-site Payment Clause Need to Cover?
A well-drafted off-site payment clause has four components.
The scope: which specific items or categories are covered. “All aluminum cladding panels manufactured under drawing series C1 to C8” is enforceable. “Off-site fabrication generally” will be disputed at the first disagreement.
The trigger: what constitutes completion for billing purposes. Specify whether it means all items in a delivery batch, all items for a named zone, or all items on a schedule of quantities attached to the contract. A reference to drawing numbers removes ambiguity.
The inspection mechanism: who certifies that fabrication is complete, and within what timeframe. Options include a joint shop visit with the main contractor’s representative, a third-party inspection, or a submitted report and photo set with a defined response window. If no response arrives within the specified period, the stage is treated as approved.
Title and insurance: who owns the fabricated items once the off-site payment is made. Many main contractors require title to vest in the owner on payment, as protection if the subcontractor becomes insolvent before delivery. If you agree to this, confirm that your insurance policy covers items for which title has passed but which remain in your custody.
A Worked Example in Metalwork
A steel contractor is producing canopies, staircases, and balustrades for a mid-rise development. The shop starts cutting and welding in month 1. Installation across four floors runs from month 4 to month 7. The original billing schedule has three stages, all triggered by on-site milestones.
The contractor negotiates an additional stage: “80 percent of steel fabrication complete, evidenced by a shop inspection report agreed by both parties.” This stage falls in month 2. It covers roughly 35 percent of the contract value.
Billing in month 2 instead of month 4 shifts the invoice date by two months. On 60-day promissory note terms, the invoice from month 2 matures in month 4. The invoice from month 4 under the original schedule would have matured in month 6. The fabrication stage does not make cash arrive faster than the note allows; it makes the note start running sooner.
This example is illustrative. Actual timing depends on the shop programme, contract value, and what documentation the main contractor agrees to accept.
What Documentation Supports an Off-site Stage Claim?
An off-site payment stage moves faster when the submission package is complete on first submission. A strong package includes: a schedule of fabricated items referenced to drawing numbers and quantities; a dated photo set showing completed items tagged with the project name and your company name; a copy of any inspection record or the written notification sent to the main contractor; and a note of any items excluded because rework is pending.
Submit the package to whoever on the main contractor’s side has authority to certify it, not just to the site team. Shop stages are often outside the site manager’s authority, so confirm the right recipient before the package goes out.
Does a vesting certificate change what you can do with the fabricated items?
A vesting certificate transfers title of fabricated items to the main contractor or owner before those items arrive on site, protecting the paying party if the subcontractor becomes insolvent before delivery.
Some main contractors require one as a condition of any off-site payment. If the contract includes this requirement, review the wording before you sign. Some certificates pass both title and risk. Others pass title only, leaving you responsible until handover. Your insurer should know which version applies before fabrication starts.
Can retention be held on off-site payment stages?
Yes, unless the contract says otherwise. Retention is typically calculated on all interim payments, and an off-site stage is an interim payment. If you are negotiating a new contract, ask whether the retention rate on off-site stages can be capped or deferred to the first on-site stage. The risk profile is different when the material is in your possession and has not yet been incorporated into the building, and some main contractors will accept a modified rate on request.
What if the main contractor refuses an off-site payment clause?
You have three routes. First, check whether the contract has a provision for materials stored in a secure off-site facility. Some standard form contracts include this, and it may extend to a certified fabrication shop. Second, price the extended cash flow exposure into the tender. If you will fund five months of shop production from your own credit, that cost belongs in the tender price, not in your margin after signing. Third, some main contractors will approve an off-site payment informally through a letter or variation order for large-value items. Get any such agreement in writing before fabrication begins.
How do I prove fabrication is complete without an on-site inspection?
A shop visit report with photos, tagged items, and drawing references is the standard method. If the main contractor cannot attend, ask them to appoint a third-party checker or accept a video walkthrough confirmed in writing. The goal is a document trail that could withstand a payment dispute, not just an internal email from your production manager. A written submission with a defined response window puts the burden on the main contractor to object or approve.
If you are preparing for a project with significant shop fabrication and want to look at how the billing stages align with your production programme, a 45-minute call is the most direct way to map them together.