Unforeseen works on a refurbishment site: instructions, variations and provisions

The most important rule of site control in refurbishment is the 48-hour rule: every surprise discovered during the works must be the subject of a written instruction recording it within 48 hours, and no remedial work should start before that instruction. The rule can look administrative and obstructive. It is in fact protective for every party.

Without an immediate record, three problems appear. The date of discovery becomes disputable, since the contractor can argue it found the problem earlier and the site was already disrupted. The quantities become hard to establish after the event, because a joint record with photographs is impossible once the remedial work has begun. And the basis of valuation is argued over, since the contractor can maintain it carried out the work without any agreement on price.

ℹ The four-step protocol Step one, discovery: the contractor notifies the design team in writing, with immediate photographs. Step two, joint inspection: the design team attends within 24 to 48 hours to record the situation with the contractor, with joint photographs and measurements where possible. Step three, the written record: the instruction describes the situation factually, states whether work in the zone is to be suspended, and sets, if the conditions of contract provide for it, the time within which the contractor is consulted on the price. Step four, provisional prices then variation: for a public contract that refers to the CCAG-Travaux 2021, the site instruction ordering the varied work, approved beforehand by the client if it changes the time for completion, the duration or the amount of the contract, sets provisional prices, fixed by the design team with the client's agreement after consulting the contractor, and the work resumes on that basis; the contractor has thirty days to submit its observations, and the variation then settles the final prices, unless its silence has made them final (art. 3.8.1, 13.4 and 13.5). In a private lump sum contract, the extra is authorised in writing, with an agreed price, before the work resumes (Civil Code, art. 1793).

The first two are marked critical because they involve either a legal obligation, for asbestos, or an immediate safety risk, for structure. In both cases suspending work in the zone is not optional: it precedes the written record and has to be confirmed in writing within hours of the discovery.

Three cases arise in practice.

The surprise concerns an item identical or close to a line already in the contractor's pricing schedule. Valuation is the scheduled rate times the quantity recorded. That is the simplest case and the quickest to agree, a masonry repair, for example, where the rate is already in the schedule per square metre.

The item is not in the pricing schedule but corresponds to work referenced in the contractor's schedule of rates or in sector price references. Valuation is on the scheduled rate, to be checked by the design team against market prices.

The item is entirely new, with no reference in either schedule. The contractor submits a build-up, labour, materials and plant, to which the overhead and profit percentages set in the conditions of contract are applied. The design team checks the labour constants and the material prices. It is the longest procedure, but it is indispensable for complex work.

ℹ The temptation of the lump sum, to be resisted in refurbishment When a surprise appears, the temptation is to agree a global lump sum verbally with the contractor: "call it 15 000 € for the whole structural repair". That approach is dangerous for two reasons. First, the lump sum is fixed before the real extent of the work is known; if the repair turns out larger, the contractor claims more with no contractual basis. Second, a lump sum with no build-up is hard to defend at final account if the client disputes the amount. Good practice: unit rates times quantities measured jointly, even if the negotiation takes a few days longer.

The variations dashboard is the central document of financial control on a refurbishment site. It centralises every variation in progress, its status, its value and its effect on the programme. Updating it weekly is indispensable to catching an overrun before it becomes uncontrollable.

The example shows a site running at 4,0 % of variations against the total original contracts (767 000 €), without complete surveys. The signal to watch: as soon as the signed variations exceed 10 % of the original contract, a warning threshold adopted by this page and not a ceiling: in a public works contract, a low-value modification is limited to 15 % of the original contract, cumulatively (R2194-8 and R2194-9), and the other grounds have their own limits, the design team has to tell the client and check that the contingency will absorb the variations still identified.

Beyond the variations, financial control on a refurbishment site has to track the valuations paid, the balance to pay on each package, and the contingency remaining. That dashboard is produced monthly and issued to the client for each site meeting.

The dashboard shows a site at the halfway point: 68 % of the valuations have been paid, 539 500 € against 789 700 €, with 28 700 € of contingency remaining, enough to absorb the variation awaiting signature at 7 800 €. The finishes package has had no valuation yet, which is normal at this stage but worth watching if the programme slips.

The final account on a refurbishment is more complex than on new build, because it carries the variations, the price adjustment, and the release of whatever contingency remains. Beginning to prepare it from the middle of the works avoids arriving at closure with unresolved disagreements.

• Check that every recorded instruction was followed by a signed variation: an instruction with no variation is an uncontractualised surprise and a claim at final account.

• List the variations in progress and their status: any variation unsigned 30 days before completion is a source of dispute.

• Calculate the price adjustment for each package: the parametric formula with the published indices applies in refurbishment exactly as in new build.

• Settle the contingency: whatever is not spent is not paid: the account takes in only the work actually carried out (CCAG-Travaux 2021, art. 12.3.1), and the sum stays in the client's budget; it does not accrue to the contractor.

• List the snags and their value: snags raised at completion and not cleared within the contract period give rise to deductions in the final account.

The 48-hour rule: every surprise must be recorded by written instruction before any remedial work, and no varied work should ever start without one. The protocol has four steps: written notification, joint inspection with photographs, the written record, then a price and a signed variation before work resumes. The five standard surprises are decayed structure and residual asbestos, both critical and requiring immediate suspension, non-compliant services, masonry behind render, and the contingency running out. The valuation hierarchy runs from the pricing schedule to the schedule of rates to a new rate built up from net cost. Avoid the global lump sum: use unit rates times jointly measured quantities. The warning signal is variations above 10 % of the original contract. Preparing the final account starts at the halfway point, not at completion.

The nature of the figures quoted

The percentages and amounts quoted on this page are orders of magnitude for framing, not measurements. They illustrate mechanisms and proportions, and they substitute neither for a tender exercise nor for an estimate prepared on drawings.

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