Buildings are major contributors to greenhouse gas emissions, responsible for about 40 per cent of these emissions according to the World Green Building Council. We know that to combat climate change, retrofitting and reusing existing buildings, be those heritage or not, is crucial. Adaptive reuse of existing structures, including substantial changes with minimal intervention, has been a key goal for heritage architects and consultants. As a heritage consultant, I believe the design and technical decisions involved in saving buildings are as important as the long-term environmental impact of the structures.
Being educated as an architect in Cuba, a country with limited resources, taught me the importance of creatively repurposing buildings. In Cuba, my work spanned institutional, residential, commercial, and religious projects. In my work as a Principal and Heritage Specialist here in Canada at GBCA Architects, I have drawn on both my Canadian and Cuban experience to preserve a variety of buildings – some of national iconic status, such as Massey Music Hall in Toronto, and Mackenzie Hall in Windsor, and some being simply old buildings.
Architects, particularly heritage architects and their consultants, have a responsibility to advocate for a responsible process throughout. However, there are obstacles that have made the key goal stated above difficult to achieve. Some of the obstacles are technical, some are not.
The non-technical obstacles range from legislative challenges to the misunderstanding that Canadian heritage is “not old enough”, and that “heritage is expensive”. Let me address these concerns.
A key obstacle is the misconception that preserving heritage is expensive. I see part of my role, when advocating for preserving a building, is to help clients understand the financial benefits of a heritage conservation strategy.
Reusing existing materials and assemblies results in saving money by reducing construction times and by reducing the time and labour costs related to demolition. Add to those costs the removal of materials, their disposal, possible street and transit closures that are sometimes required for demolition, and the overall financial tally can be substantial.
Encouraging clients to see that preservation of existing buildings not only saves money by reducing construction times and avoiding demolition costs but also demonstrates goodwill towards our heritage and a commitment to reducing carbon emissions. Thankfully, these non-monetary issues matter more and more to today’s end-users of buildings. Clients, including some developers, are responding positively.
For example, GBCA was hired to renovate a late 19th century building ( circa 1893 ) in Toronto’s west end. The objective was site intensification for new rental residential units. The building was not designated or registered, but simply an “old building” typical of that community. It was part of a crowded neighbourhood, on a busy transit line, had lots of site constraints and a challenging heritage assembly.
Our first approach was to assemble a team of consultants experienced in heritage work.
We were able to show the client that they would save money by re-using the existing bricks and other materials which would reduce demolition deliveries, not require road closures or special permits, nor require expensive crane use.
The use of new material was confined to reinforcement requirements and some partitions and interior finishes. Key to this project, was the ingenuity of the code consultant, Allan Larden, who provided a resourceful technical rationale for reuse of the stairs. These wrapped around the elevator and therefore didn’t meet “current code”. Paradoxically, he proposed acceptable upgrades so the staircase could be saved and used as another mean of egress, thereby meeting Ontario Building Code.
With the creativity of the entire team, we were able to re-use about 80 per cent of the structure.
The technical obstacles to adaptive reuse of existing structures include the lack of research-backed data (fire ratings, engineering properties, etc.) and the lack of knowledge about historic materials and their assemblies, especially in non-heritage trained consultants. And, as demonstrated above, dismissing heritage as not meeting “current code” without creatively assessing the opportunity.
Though rich in history, we still do not have many reliable sources about materials and the methods used in Canada’s architectural past. This lack of data makes it difficult to demonstrate evidence-based reasons to preserve materials and/or integrate heritage with current building code requirements.
As a heritage consultants, we advocate for reusing existing materials and assemblies by showing how historic materials and wall assemblies work. For instance, a weak wall assembly such as clip bond (known also as hidden header) can still be reused. GBCA did just that for a recent adaptive reuse project (see below). Thanks to teamwork and our solid understanding of both heritage construction techniques and of assembly systems, it was another heritage-related success.
To achieve this success, we worked with Montgomery Sisam Architects, LEA Consulting Engineers and Clifford Restoration on a project for the Toronto Catholic District School Board at the former Scarborough Foreign Mission, a religious building retrofitted to a new school. We kept most of the structure and avoided an expensive and a retention system that was not environmentally friendly.
Research via historical photos provided valuable insights into the 1923 building’s construction method of clay tiles, steel columns and steel structure. Armed with this knowledge, the design team considered three options.
One option did away with the heritage elements entirely by introducing a façade retention option and was not environmentally friendly either. Another option required full reinforcement yet kept the historical element but had negative impact on the schedule and raised environmental concerns.
The third option was a hybrid approach: reuse existing elements in a “top-down” carefully scheduled construction/demolition sequence. We chose the third option.
By applying a “top-down” construction/demolition approach, we were able to reuse the existing steel beams with a new concrete deck, avoiding more disruptive methods and moderating the environmental impact. We also re-used the existing clay tiles in each level as form for the new concrete and the proposed shoring salvaged and reused in each level. I used this method successfully in Cuba for an adaptive reuse of a former 1920s convent to a hotel almost 20 years ago.
Teamwork and knowledge are helpful remedies to our obstacles. Consultants are critical to heritage architects and, as we all know, they can be a friend or a foe to one’s project strategy.
Additionally, our industry could make more progress by addressing the obstacle of our own lack of technical knowledge about heritage buildings. Our educational system needs to include more heritage-related content to encompass heritage building science and pathology. This will help build a community of professional consultants who can offer practical solutions for integrating existing building assemblies with current building codes. This is particularly important as Canada’s inner-city structures age and demand for consultants skilled in heritage work increases.
In conclusion, reusing existing buildings offers significant benefits to society, the environment, and the economy. To achieve this, I encourage architects and related consultants to involve heritage professionals early in their projects and to enhance their technical understanding of heritage practices. Incorporating these practices into educational programs across various built-environment disciplines will foster a more holistic approach to building preservation and sustainability.
Carlos Morell has 30 years’ experience in conservation and historic preservation. Trained as an architect at the Havana University, Cuba, he studied Conservation and Rehabilitation of Cultural Heritage before moving to Canada. He started working at GBCA Architects in 2007 where he currently oversees all technical aspects, including drawings, specifications, masonry rehabilitation, building envelope analysis, integration of new technologies into heritage buildings and contract administration.
Carlos is a Principal with GBCA Architects in Toronto and has worked on heritage properties including Fort York, Union Station, Ontario Legislative Assembly, Mackenzie Hall (Windsor) and Massey Music Hall.
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