The building sector generates a significant share of our companies’ greenhouse gas emissions. We have long realized the importance of maximizing the energy efficiency of buildings in order to reduce the energy required for building operations, particularly for heating and cooling. In Québec, most of the energy consumed by our buildings comes from a renewable source that emits less GHG—hydroelectricity. Increased energy efficiency leads not only to environmental benefits but also to substantial savings. It is only more recently that we have begun to consider the environmental footprint of the construction materials. Globally, this impact is generally less than that of operating energy. However, because of the low carbon impact of our electricity source, Québec’s situation is unique. Since the impact of operating energy is lower, a large part of the environmental footprint of Quebec buildings is due to the manufacturing process of construction materials. Therefore, the choice of these materials is even more important here than elsewhere in the world!
In addition to requiring relatively little energy for its processing, wood, a material that is directly derived from the capture of CO2 from the atmosphere, will sequester it for the life of the building! Several in-depth studies, using life cycle assessment methods and real buildings, have quantified the advantage of wood over other materials used in construction and derived from non-renewable resources, such as steel and concrete.
This is why the gouvernement du Québec launched the Wood Charter in 2013. The goal was simple: to help fight climate change and boost the vitality of the local economy by promoting the increased use of wood in construction. Just a year ago, the Policy for the use of wood in construction was announced as a continuation of the Wood Charter. It announced a series of measures to promote the use of wood in the construction of buildings and civil engineering works, a portion of which is funded by public funds. The option to use wood as the principal structural material must be evaluated at the pre-project stage. Where the use of wood is technically and economically feasible, this option should be preferred. These first steps pave the way for carbon footprint requirements for publicly funded construction projects in the future. Although we are not there yet, it is essential to set the stage by providing tools for the departments, agencies and partners involved in the design of these buildings to assess the carbon footprint of their projects. Life cycle assessment methods, while appropriate for this exercise, are complex and require considerable expertise, making their use inaccessible. To address this issue, the team of the Centre d’expertise sur la construction commerciale en bois (Cecobois) worked together to create Gestimat.
Gestimat is a tool developed specifically for the Québec context that estimates greenhouse gas emissions associated with the manufacture of structural materials included in a given construction project. Although it is not a life cycle assessment tool per se, it greatly facilitates the comparative analysis of the carbon footprint due to the choice of materials in the building sector. In the very early stages of a project, it is possible to compare different scenarios involving different materials and building systems, and then make an informed choice.
Gestimat stands out from most tools in the ease with which assessments can be done very early on in a project. Gestimat’s user-friendliness and originality are of interest to both the public and private sectors as it democratizes the process of analyzing the environmental footprint of buildings. The tool reveals the importance of material selection, which has a significant impact on reducing GHG emissions from buildings!
—The Gestimat team from Cecobois
The future is bright for Gestimat, which will definitely help reduce the carbon footprint of the building sector in Québec, but also elsewhere in Canada. As evidence of the value of the tool, it has already been adapted for Ontario, and more partnerships are to come! Although Gestimat currently considers only the materials used in the structure, the tool is bound to keep getting developed. This includes the inclusion of materials used in the building envelope, such as insulation and exterior siding, by the end of next year. Eventually, the use of the tool could also be extended to other types of construction where wood has its place. Take, for example, some civil engineering works, such as bridges in forest areas.