Every project we take on starts with the same slide, and it is not a render. It is a two-column table: what it costs to keep the building, and what it costs to replace it — in euros and in tonnes.
The numbers move the conversation
Clients are rarely persuaded by carbon in the abstract. They are persuaded by carbon that arrives attached to a programme risk and a cost line. A demolition on a constrained urban site is nine to fourteen months of programme before anyone pours anything.
On Kade 14 the reuse route was 31% cheaper and eleven months faster. The 1,900 tonnes of avoided CO₂e was, honestly, the third argument in the room.
Where reuse genuinely fails
We are not absolutists. Reuse fails when floor-to-floor heights cannot carry modern services, when the structure is contaminated, or when the frame cannot take the loads the new use demands. We have recommended demolition twice in fifteen years and would again.
The point is not that keeping is always right. The point is that keeping should be the default that has to be argued away, rather than the exception that has to be justified.
What we ask for at week one
A structural survey, a floor-to-floor section, and a materials audit. Three documents, roughly six weeks, and usually less than 1% of construction cost. It is the highest-leverage money on the whole project.
Written by
Ilva Sørensen
Partner, Technical
Ilva owns delivery: structure, envelope, energy and the long negotiation with reality that turns a drawing into a building on budget.
