How are new technologies integrated into heritage construction sites?

The use of new technologies during project implementation has now become an integral part of the tools used by heritage architects for site monitoring. Contractors are also increasingly benefiting from their use. What is less well known is that data collected through laser scanning can also be a valuable tool during construction supervision and implementation.

At the Citadel of Québec, beyond dimensional information, point clouds can be analyzed through verticality studies to validate deformations in walls and other structures on the project. Deformation is expressed through colour mapping based on the distance of a point from a perfectly vertical reference plane. This study makes it possible, at a glance, to understand the wall deficiencies that need to be corrected—such as leaning, bulging, or other anomalies. Engineers and architects collaborate in interpreting this information and, together with the contractor, integrate these tools into the daily work of the site foreperson. On site, this approach allows for precise identification of intervention areas and their scope.

The process is then combined with two additional scanning stages to assess the exact volume of stone infill in massive masonry walls replaced by the contractor. The first construction scan is carried out once dismantling by the mason is complete, and the second scan is performed once the project is finished. In heritage masonry projects, infill volume is often a major financial issue. By subtracting the two scans, the actual volume replaced by the contractor can be accurately calculated. In this context, the contractor is paid fairly, professionals avoid disputes and unproductive exchanges, and all stakeholders work within a harmonious, honest, and respectful framework.

This same approach was applied to the Nouvelles-Casernes project, but in this case, point clouds were also used from a conservation perspective—to preserve traces and elements of the past. The seven buildings that make up the Nouvelles-Casernes still bear the marks of various construction campaigns carried out on their walls from their initial construction in 1749 until the departure of the Canadian Cartridge Factory in 1964. These walls now carry vestiges of their past, the marks of continuous military presence until 1871, and the scars of a bygone industrial era.

How can walls be restored and consolidated without permanently erasing these elements that embody the richness of each period of occupation and give these places their exceptional atmosphere? This is where new technologies enable architects to reintegrate key evidence, reconstruct unexplained assemblies of incongruous materials, reinstate mechanisms whose roles are still not fully understood, and ultimately rebuild walls using original techniques—out of respect for the work of the hundreds of soldiers, masons, and carpenters who left their mark through their craftsmanship.

The precision of the information collected at the beginning of the project is then transmitted to the construction site, making it possible to pass these traces on to future generations, with the utmost respect for our predecessors. These images speak for themselves, revealing the indispensable contribution of new technologies.