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Atwill-Morin provided masonry restoration for the iconic Château Frontenac in Québec City. The National Capital Commission's Lady Grey Wall and Escarpment project. M A R C H 2 0 2 5 | 21 Restoration Products & Services P H OTO G R A P H Y BY S T ÉP H A N E G RO L E AU/CO U RT E S Y AT W I L L- M O R I N ; H EI D EL B ERG M AT ER I A L S The restoration sector is thriving as experts revive some of Canada's most iconic buildings by ROBIN BRUNET F rom professionals who carry out the work to those who supply the mate- rials they require, the restoration sector is a perpetual source of brisk business, and product innovation. In Canada, concrete and masonry restoration is prevalent from coast-to- coast, for projects both utilitarian (infrastructure) as well as of cultural significance – with Ottawa a hot- bed of historic structures requiring rehabilitation. Two examples: the National Capital Commission's Lady Grey Wall and Escarpment project and the repurposing of the West Memorial Building, both of which rely on the products and expertise of Heidelberg Materials. The West Memorial Building, constructed between 1954 and 1958, had never undergone major repairs or renovations until 2018, when EllisDon was tasked with securing its 20,000 square feet of usable space for the operations of the Supreme Court and Federal Courts. Since then, the rehabilitation has involved reinforcing the building, replacing mechanical, electrical, and life-safety systems, and making seismic upgrades. Structural work includes the com- pletion of new shear walls, reinforcement of beams and columns, and installation of new slab toppings. Additionally, building envelope and heritage work has involved mortar replacement, stone repairs, window restoration, and new roofing. Back To The FUTURE "We are bound by security not to discuss cer- tain aspects of this project, but we can disclose that we used lightweight concrete solutions for the floor slabs, with a total of 1,000 cubic metres being poured 100 cubic metres at a time. SCL concrete was used for the structural walls, and the sheer scope of work necessitated a vast array of mixing designs," says Kevin Chevrier, Ottawa-based QC manager at Heidelberg Materials, who adds that the project is expected to wrap this summer. The Lady Grey retaining wall, built between 1911 and 1913, reaches 10 metres at its highest point and spans 580 metres along the Ottawa River, from the National Gallery of Canada to Sussex Drive. The NCC is repairing the Lady Grey wall to protect its structural integrity, as parts of the wall began to collapse in 2020. This project is also scheduled for completion this summer. The restoration work was extensive and included the installation of piles and shoring along the north section, demolition of the existing north section of the wall and railing system along Lady Grey Drive, instal- lation of caissons, and the demolition and rebuild of the first 125 metres of the south wall section. Heidelberg Materials is supplying over 3,000 cubic metres of evoBuild low-carbon concrete for the project. Specifically, the mix design for the wall sections, which represent the vast majority of the project, is ES435201V – evoBuild Silver Low Carbon 35 MPa Flowcrete. This evoBuild product offers more than a 50 percent reduction in the carbon footprint from the Canadian Ready-Mixed Concrete Industry-Wide 2017 baseline, resulting in a reduc- tion of over 470,000 kg of carbon dioxide (CO2) for this wall restoration alone. Matthew Atwill-Morin, president of Atwill-Morin, a Montreal-based stone masonry restoration special- ist, reports that his organization has been particularly busy with restoration projects in the Maritimes lately. "That includes the restoration of the Carleton Martello Tower in Saint John, New Brunswick, which dates back to the War of 1812," he says. The second and final phase of this rehabilitation project focused on replacing the fire command post atop the tower. Maxim Construction deconstructed the command post. "We created pockets in the stone wall to accommodate granite blocks, allowing for the installation of steel beams to reconstruct the command post above," says Atwill-Morin. "Once this phase is completed, we will return to work on the brick vault below." Atwill-Morin's team is expected to return to the site in late winter to reconstruct the stonework around the granite blocks once the beams have been installed. Atwill-Morin has also been working on the restoration of the legendary Province House in Charlottetown, PEI, for the past two years, with completion expected at the end of 2025. Since the building should retain its significance both as a tour- ist attraction and a historical landmark, work crews have undertaken trenching of ancestral brick walls, the fabrication of openings in load-bearing masonry walls for the passage of mechanical conduits, the replacement of stone paving in interior corridors, and the installation of Wallace-type natural stone alongside the assembly of exterior staircases. Yet another Maritimes project is the Cape Breton Regional Hospital, completed this year. The work has focused on the building envelope, includ- ing masonry solidification, repointing, spot brick replacement, and the installation of Helifix-type

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