Implementing a performance framework and experimental validation of lime render systems for built heritage in northern climates
Understanding the relationships between render, masonry and climate to improve built heritage conservation. This research combines architectural history, materials science and experimentation to develop compatible, durable solutions with a lower carbon footprint.
Funding and allocations
| Funder and programme | Period | Amount or support awarded |
|---|---|---|
| NSERC · Alliance grant Budget of the collective project led by Luca Sorelli. Awarded in August 2026. Fabio Sedia: co-investigator, heritage component. | 2026–2029 | CAD $223,228 |
| Start-up funds · preparatory phase Allocation for research assistance on the literature review and sources. Included in the CAD $20,000 start-up fund. | 2025–2026 | CAD $4,924.80 |
Publications and outcomes
- OngoingHistorical and contextual analysis of renders, architectural surveys and compilation of reference data for assessing render–masonry systems.
- PlannedTwo pilot projects, optimized formulations incorporating calcined clays, a performance-based technical guide, an open database and professional training.
Protocols and agreements
Eight reference formulations: four mixed on site and four commercial products. Assessment of moisture, drying, adhesion and durability; laboratory characterization, hygrothermal modelling and validation of three optimized formulations in a second pilot.
Partners and institutional support
Main partner: Centre de conservation du Québec (MCC). Team: Université Laval (civil engineering, CRIB-UL, iM2S and School of Architecture) and Université de Carthage. CCQ professional network: including Maçonnerie Murphy inc. and Les Enduits Art Béton inc.
The project
The research treats render and masonry as a system whose performance depends on materials, application methods and building use. It combines historical analysis, architectural observation, laboratory testing and monitoring on site to better understand the compatibility and durability of lime renders in Canada’s northern climate.
Challenges and objectives
The project has two objectives: to establish an assessment framework based on measurable performance indicators, and to design and validate formulations suited to historic masonry and cold climates. The research examines moisture transfer, drying, adhesion, mechanical compatibility and resistance to salts and freeze–thaw cycles. Incorporating calcined clays available in Canada also aims to reduce the carbon footprint of the formulations while preserving their compatibility with existing buildings.
Fabio Sedia’s contribution
As co-investigator responsible for the heritage component, Fabio Sedia contributes to the historical and contextual analysis of renders from the seventeenth century to the present. Archives, measured surveys and building observation connect formulations and craft knowledge with architectural types, substrates, orientation and occupancy conditions. He is the academic supervisor of the two planned master’s projects, co-supervised by François Dufaux, whose expertise concerns the history and conservation of Québec’s built heritage. This work uses architectural knowledge to define tests, interpret results and guide interventions.
Research team
Luca Sorelli, principal investigator and director of CRIB-UL and the iM2S research group, leads the project scientifically. Josée Duchesne oversees physicochemical and microstructural characterization and co-supervises the doctoral project with Luca Sorelli. Fabio Sedia and François Dufaux supervise the master’s research in architecture. Elizabeth Cloutier and Isabelle Paradis, conservators at the Centre de conservation du Québec, co-lead field activities and pilot projects. Karima Zoghlami, from the Université de Carthage, contributes to the characterization of historic mortars, formulation optimization and compatibility protocols.
Partners and fieldwork
The Centre de conservation du Québec (CCQ), part of the Ministère de la Culture et des Communications, is the main partner. It connects field needs with research at Université Laval’s Department of Civil Engineering and School of Architecture, and with expertise at the Faculté des sciences de Bizerte, Université de Carthage. Its professional network, including Maçonnerie Murphy inc. and Les Enduits Art Béton inc., is involved in on-site validation and knowledge transfer. The first pilot project is planned on a heritage building in Old Québec.
Methods and pilot projects
The first strand combines historical analysis and on-site validation: eight reference formulations, four mixed on site and four commercial bagged products, are to be compared in Old Québec. The second strand provides detailed laboratory characterization and investigates mixtures of lime and calcined clay, with or without a controlled cement addition. The measurements inform modelling of heat and moisture transfer. Three optimized formulations are then to be evaluated in a second pilot project on an instrumented experimental wall.
Expected outcomes and knowledge transfer
The project aims to produce a performance-based technical guide for use across Canada, an open database, validated formulations and tools for selection and application. The CCQ will help translate the findings into recommendations and training for architects, craftspeople and heritage managers. Two master’s projects in architecture and one doctorate in civil engineering are planned. These outcomes are intended to support more durable interventions and help extend the life of existing buildings.
Funding and timeline
The project is underway for the 2026–2029 period. An Alliance grant from the Natural Sciences and Engineering Research Council of Canada (NSERC) was awarded in August 2026. Project funding: CAD $223,228.
