1. Refurbishment is not new build with extra constraints
The idea that an architect can handle the economics of a refurbishment alone, having already done so in new build, rests on a fundamental confusion. In new build the economist checks and optimises. In refurbishment the economist reveals and protects.
Reveals: the hidden items, asbestos removal, demolition, substrate preparation, the provisions calibrated on the actual building rather than on generic rates, and the grants that cut 30 to 50 % off the net cost of the project. Protects: with conditions of contract adapted to existing fabric, a procedure for the unforeseen that prevents badly valued variations, and a structured bill that makes tender comparison possible and the final account defensible.
Those duties call for expertise specific to refurbishment, the rates, the technical codes as they apply to existing fabric, the asbestos procedures, the voting rules in a block of flats, the grant thresholds, which few architects have had the time to develop against the volume of projects they carry.
2. The six critical duties
| Duty | Without a dedicated refurbishment economist | With one | Economic risk avoided |
|---|---|---|---|
| Feasibility estimate | New build rates applied to refurbishment, strip-out and contingency omitted | Refurbishment rates by type of work, strip-out, surveys and contingency reflected, the range stated | Initial understatement of 20 to 40 %, and a falling-out with the client at tender |
| Reflecting the surveys | Surveys commissioned but the findings never reflected, the provision ignored | Asbestos and lead removal priced and reflected from developed design, the provision calibrated | Asbestos found on site adds 50 to 200 €/m² with nothing provisioned |
| Conditions of contract | Standard new build conditions with no unforeseen conditions clause | Clauses for unforeseen conditions, occupation, hidden work, phasing, and liability for retained fabric | Every surprise becomes an ad hoc negotiation, and variations run at two to three times market price |
| The bill of quantities | A new build bill with no strip-out, substrate preparation or disposal | A bill separating removal from installation package by package, with the refurbishment items and units | An incomplete bill makes the tenders incomparable and the final account contentious |
| Tracking the unforeseen | Late or missing records, lump sum valuations contested at final account | The 48-hour protocol, a variations dashboard, valuation on the contractual hierarchy | A final account contested on undocumented surprises, and a dispute with the contractor |
| Retrofit payback | A gross budget presented with no grants, the client deciding on an overstated cost | The net cost after grants, the loan instalment against the savings, scenarios compared | A decision blocked on a gross cost when the net cost is 30 to 50 % lower |
The table makes a point that is often counter-intuitive: the refurbishment economist does not cost, but earns. On each of the six duties the value protected systematically exceeds the fee. That is not a sales argument: it is a calculation any architect or client can verify on their own projects by comparing the initial estimate with the final cost on work carried out without a dedicated economist.
3. What the appointment actually costs
Fees for a complete refurbishment appointment generally run at 1,5 to 3 % of the works budget, less in absolute percentage terms on large projects, more on small ones. The percentage is calculated on the initial budget, not on the final one including variations.
A project of 150 000 to 300 000 €: 2 500 to 6 000 € for a complete appointment, from estimate through contract documents and bill to variations and final account.
A project of 300 000 to 700 000 €: 5 000 to 15 000 € depending on complexity and the number of packages.
A project above 700 000 €: 12 000 to 25 000 €, quoted on the exact scope.
These ranges correspond to an integrated appointment from feasibility to final account. Some clients split it, taking an economist for the design and tender only, or for site supervision only. That is possible but less effective: an economist who did not draft the conditions of contract is less well armed to defend the client's position when the variations are negotiated.
4. The return, in three scenarios
| Scenario | Works budget | Estimated fee | Economic risk avoided | Return on the appointment |
|---|---|---|---|---|
| Refurbishment of a 200 m² dwelling | 180 000 € | 2 500 – 4 000 € | Initial understatement avoided, 20–30 k€; unforeseen conditions clause, 8–15 k€ | Seven to eleven times the fee |
| Refurbishment of a twelve-flat block | 380 000 € | 5 000 – 8 000 € | Net cost after grants correctly calculated, 40–60 k€; variations controlled against an unplanned 15 %, 30–50 k€ | Ten to fourteen times the fee |
| Refurbishment of a 600 m² public building | 650 000 € | 9 000 – 15 000 € | Accessibility not reflected, 20–40 k€; unforeseen conditions, 30–80 k€; final account dispute, 20–60 k€ | Eight to twelve times the fee |
ℹ The calculation few architects make On refurbishment projects run without a dedicated economist, the gap commonly observed between the initial estimate and the final cost sits around 20 %, and frequently exceeds 25 % on buildings from before 1970. On a project of 250 000 €, that gap is 45 000 to 60 000 €. The economist's fee on the same project is 4 000 to 6 000 €. The question is not whether the appointment pays for itself; structurally it does. The question is whether the client and the architect build that calculation into their initial decision.
5. The decision grid
Not every refurbishment needs a full-scope appointment. The grid below helps decide by project profile.
| Situation | Outsource | Keep it in-house | Decisive signal |
|---|---|---|---|
| Works budget above 150 000 € | ✓ Recommended | Risky; the cost of an error far exceeds the fee | The threshold at which the fee is under 3 % of the budget |
| A building from before 1970, or with known defects | ✓ Strongly recommended | To be avoided; asbestos, lead and unknown structure cannot be managed without the expertise | The presence of risks requiring the surveys to be reflected |
| A public building with outstanding accessibility obligations | ✓ Recommended | Risky; accessibility carries both a consent risk and a litigation risk | Consent refused, or non-compliance at completion |
| A block of flats with a vote to come | ✓ Recommended; the apportionment table and financing plan are indispensable | Possible where the budget is under 80 k€ and the block is simple | A meeting to be convinced with financial data |
| An energy retrofit with grants above 20 k€ | ✓ Recommended; optimising the grants gains more than the fee | Risky; grants miscalculated or badly sequenced mean real losses | The grants exceed the fee for the appointment |
| Light refurbishment under 50 000 € with no defects | Optional | ✓ Acceptable; the fee is disproportionate to the budget | A budget under 50 k€ on a recent building with no defects |
The most reliable signal is simple: does the economist's fee represent less than 3 % of the works budget? If it does, and it does as soon as the budget passes 80 000 to 100 000 €, the appointment is economically justified on the risks avoided alone, independently of any other consideration.
6. Three questions before going without
Before deciding not to include an economist in the team, three questions deserve an honest answer.
One: who is going to reflect the asbestos and lead survey findings in the estimate and calibrate the provision? If the answer is nobody, or we will see on site, the risk of overrun is high.
Two: who is going to draft the unforeseen conditions clause, with its valuation procedure and dedicated provision? Standard conditions do not protect the client in refurbishment.
Three: who is going to keep the variations dashboard during the works and prepare the final account with the price adjustment? If it is the architect on top of the design duties, the risk of error or omission is significant.
If those three questions have no clear answer, the appointment is not an option, it is a necessity.
In summary
The refurbishment economist reveals the hidden items and protects the client with the right contractual tooling, two duties distinct from the architect's. The six critical duties are the estimate on refurbishment rates, reflecting the surveys, adapted conditions of contract, a structured bill, tracking the unforeseen under the 48-hour protocol, and the payback with the grants reflected. The cost is 1,5 to 3 % of the works budget, that is 2 500 to 15 000 € by project. The return is seven to fourteen times the fee on the risks avoided. Outsource systematically above 150 000 €, on any building from before 1970, on any public building with accessibility obligations, and on any retrofit with grants above 20 000 €. The three questions to answer: who reflects the surveys, who drafts the unforeseen conditions clause, and who keeps the variations dashboard.
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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Sources: the BT construction cost indices published monthly by INSEE on its 2010 base, used to update the figures · construction cost statistics from SDES, the statistical service of the ministry responsible for construction · regulatory texts published in the Journal officiel and consolidated on Légifrance for the requirements cited.