Pavillons du 49e – Chibougamau

FPInnovations’ Role

FPInnovations worked closely with the engineering team to design an instrumentation plan. Sensors were installed during manufacturing to monitor structural and hygrothermal performance.

Structural Behaviour and Settlement

Mid- and high-rise mass timber buildings experience cumulative vertical movement across floors due to factors such as wood shrinkage, elastic deformation, acoustic pad compression, and creep. Modular construction amplifies these effects because of discontinuities between modules.

To track differential settlement, six potentiometers were installed at critical junctions between CLT housing units and light-frame corridors, and at the stairwell interface built from tall vertical CLT panels spanning all four floors. These sensors were connected during onsite assembly, from foundation to roof, with wiring routed to the crawl space.

Durability and Hygrothermal Monitoring

Durability in mass timber construction depends on robust design practices. To validate envelope concepts for modular systems, sensors measuring temperature, relative humidity, and wood moisture content were embedded in the structure. Most were installed at the factory, with final connections completed onsite.

Instrumentation targeted junction lines between modules for two wall types, as well as floor and roof levels. Additional sensors were placed in inter-module cavities, corridors, and balcony connections. This data supports continuous monitoring of wood behaviour, condensation risk, and mold prevention, while validating simulation models.

Testing and Instrumentation

Acoustic and vibration tests were performed after construction. FPInnovations also measured deflection during module lifting and transportation using cameras, accelerometers, and potentiometers.

This project serves as a case study for the Offsite Wood Construction Handbook and provides valuable insights into best practices for modular mass timber construction.