WE ARE SURROUNDED by a sea of discarded materials that can be reused in building construction. Think of all those political signboards that we see at election time outside private houses and in other prominent locations. Temporary signs are often made of corrugated plastic that could be used as siding or insulation.
WE ARE SURROUNDED by a sea of discarded materials that can be reused in building construction. Think of all those political signboards that we see at election time outside private houses and in other prominent locations. Temporary signs are often made of corrugated plastic that could be used as siding or insulation.
Despite the opportunities to reuse discarded materials, construction and demolition leftovers make up about 35 per cent of the total waste stream in Canada. Meanwhile, the growing worldwide demand for new construction materials is putting so much pressure on natural resources that Worldwatch Institute estimates that by the year 2030, the world will have run out of many of them. At that point, building with salvaged goods and “waste” diverted from landfill won’t be the exception; it will be the norm.
At present, aluminum may come from South America, steel from Russia, glass from China and marble from Italy. We think nothing of transporting these materials over long distances even when they may be available from a local source at what could be a better price. In a post-peak-oil world, however, bulky construction materials from afar may be far more costly and their supply vastly reduced.
Some in the construction industry are beginning to recognize that in the future the key drivers for building construction and possibly even design will be closed-loop systems that use local, readily available, renewable or reused resources. In fact, green-building rating systems such as LEED already encourage such practice.
Reusing materials is actually centuries old. Medieval buildings in Europe were often constructed from stone taken from ruins of Roman buildings. The lovely Tweedsmuir church in Orangeville, Ontario, is but one wartime example. It is constructed of stone salvaged when Canada Portland tore down its nearby cement fac- tory in 1940. Boards removed from old barns in Eastern Canada have long been used as siding on homes, and builders dismantled many of Canada’s grain elevators on the treeless Prairies to salvage the old timber.
More exotic examples include Michael Reynolds’ Earthship buildings. He filled old car tires and beverage containers with compacted earth to construct the walls of buildings. And students involved with Rural Studio erected a variety of buildings for disadvantaged com- munities in Alabama mainly using locally available waste and surplus materials.
These examples are mostly ad hoc projects. A few architects, however, are interested in the creative and environmental opportunities offered by using materials sourced from local waste streams and regional renewable resources in mainstream buildings.
Mountain Equipment Coop (MEC), the environmentally conscious retailer of outdoor recreational gear, leads the charge in this practice, having used the components of old buildings in its Ottawa (2000) and Winnipeg (2002) stores. The site for their retail opera- tion in the nation’s capital was occupied for 40 years by a grocery store. MEC couldn’t reuse the supermarket, but the company carefully dismantled and catalogued all the store’s components. MEC’s architects then designed its new building around what was available, using about 75 per cent of the stockpile, including the structural grid, footings and components of the steel frame. In fact, the characteristics of the old supermarket dictated the layout, aesthetics and performance of the new store.
The Vancouver-based architectural firm Busby and Associates (now Busby Perkins and Will) used a similar process for the City of Vancouver’s materials testing facility (1999). Approximately three-quarters of the building’s structure and fabric consists of salvaged and recycled materials, including heavy timber structural members, roof trusses, existing lab and mechanical equipment, light fixtures and furniture. They even fabricated custom components such as windows by inserting glass into frames milled on site from old wood decking. By focusing on simple construction details, the designers incorporated a higher percentage of used materials.
Large infrastructure demolition projects are another source of waste material. Boston’s Big Dig involved demolishing and burying several kilometres of raised highway. Before everything went underground, one engi- neer recognized the value of the “waste” materials and utilized them for a new home, dubbed the Big Dig House (2006). The firm Single Speed Design used most of the salvaged materials from the Big Dig in the condition in which they were found. They didn’t hide the source and, in fact, utilized the particular characteristics of the materials. For instance, the reclaimed concrete slabs that previously supported the highway were easily able to carry three feet of soil for a rooftop garden. Designers, such as Single Speed, often go out of their way to celebrate the qualities and character of the old materials, and to transform them in creative ways. Viewed as old war wounds, visible scars and other features can be used in a decorative way to highlight the material’s heritage, and bring attention to its transformation.
The Dutch firm 2012 Architects uses a “harvest map” of available resources within a chosen radius from the site. They propose that in the future, there will be a new professional – the re-designer – who can recognize the potential of readily available waste and surplus mate- rials. The re-designer would understand the logistics of identification, transportation and refabrication, and would also help with structural issues and code equivalences posed by the use of salvaged materials. In some parts of the world, such consultants already exist. Their experience can reduce disruption or delay. For example, as a result of their involvement in the iconic BedZED project (2002), the UK environmental charity BioRegional Development Group established a new company – BioRegional Reclaimed. It advises architects on reclaimed materials and waste disposal, and can assess the environmental impact.
2012 Architects’ Villa Welpeloo project (2009) in Enschede, Netherlands, is an example of creative use of waste from other industries. It features a primary steel structure taken from a redundant textile mill and cladding composed of timber harvested from discarded cable reels. Cable reels are left outside most of the time so the circular sides rot. However, the more protected internal planks remain in good condition and can be easily extracted. All of equal length, they are well suited as siding. The architects actually developed a fixing sys- tem and an aesthetic for the villa based on these short timber lengths.
Real change, however, demands the widespread replication of the techniques described in these examples. The trade-off that often exists between the old and new also needs to be carefully considered. For instance, when high performance is required, such as in window-glazing systems or for water and energy appliances, salvaged materials could lower environmental performance.
In the future, project design needs to stem from an investigation of available local materials and an assess- ment of their suitability for a particular use. This requires a shift towards a flexible approach that creates the right conditions for salvaged components to influence build- ing design, since they add a new level of complexity to a project, and significantly change the design and con- struction process. Currently, standard construction and demolition practices focus on getting the job done as fast and inexpensively as possible; not much heed is paid to salvage. Reclaimed materials do not show up at the right time, in the right amount or in the right dimensions. Supplies may need to be purchased at an early stage and then stored at some expense, even before a contractor is selected.
A market for salvaged materials and surplus construc- tion components is gradually developing. Habitat for Humanity’s ReStores sell used building materials, and there is a Building Materials Reuse Association. Some demolition companies have hired employees who identify markets for building waste, and Internet-based exchange websites similar to Craigslist and eBay that focus on waste construction materials are beginning to appear.
Building codes should not be a barrier to reuse, but it can be hard to push building officials out of their comfort zone. Currently, old materials are often perceived to be inferior, when in reality the opposite may be the case. The strength, durability or other features of the used material may, nonetheless, need to be established through testing or inspection, which can add an additional cost.
Contractors are inclined to charge more for anything unconventional, since such projects often require addi- tional labour. Moreover, some designers may hesitate because sourcing salvaged materials can be time consum- ing and their use may expose those involved to additional liability. Meanwhile, owners and investors are concerned about the public’s acceptance of buildings made from used material.
As a consequence, only the most dedicated are currently willing to overcome the challenges inherent in using salvaged goods. Although material costs might be lower, particularly if the old building is on the same site as the new construction, savings may be offset by the need for refabrication, increased labour and higher design fees. Busby Perkins and Will estimates that by using salvaged materials for their Vancouver project, they saved approximately $50,000 in material costs. But some of this was spent on increased construction management fees and labour expenses.
Despite these concerns, demand for salvaged materials is likely to grow as peak oil is realized and markets become established. As this happens, the pioneering work of forward-looking designers and contractors will be much appreciated.
To view some of the buildings mentioned in this article, visit ssdarchitecture.com, mec.ca, busby.ca and 2012architecten.nl/#/Villa%20Welpeloo.
See Sidebar: Salvaging Is Timeless
Mark Gorgolewski, a professor and director of the graduate program in building science at Ryerson University’s Department of Architectural Science, is also a director of the Canada Green Building Council.
