From both an economic and environmental perspective, reducing and recycling construction waste materials makes perfect sense for members of the building profession.
While building and infrastructure projects serve as society’s most physically impressive monuments to human ambition and ingenuity, they all too frequently involve the creation of prodigious amounts of wasted material.
The squandering of these materials has an adverse effect upon both the bottom line of building companies, as well as the health of the broader environment.
The negative impact on the environment is especially pronounced given that building and infrastructure projects are undoubtedly society’s largest and most widespread physical undertakings, generating potentially copious amounts of waste.
According to figures from the Organisation for Economic Co-operation and Development (OECD), buildings account for a staggering proportion of humanity’s resource consumption and environmental pollution.
The OECD estimates that they are responsible for around 30 per cent of raw materials used globally, 42 per cent of energy consumption, 25 per cent of water used, 40 per cent of atmospheric emissions, 20 per cent of water effluents and 25 per cent of solid waste.
This environmental impact is further exacerbated by the fact that building products leave an environmental footprint at every segment of their life cycle, from the extraction of raw materials and their processing into completed goods, to their transportation to project sites and use in actual construction, to their final removal and disposal once a building’s operating life comes to an end.
Acutely aware of the negative environmental effects associated with building materials, governments around the world are adopting regulations and measures to help diminish their wastage and encourage recycling.
These include a policy launched by the Western Australian government in the middle of 2014 to send the landfill levy skyrocketing, raising the cost of disposing the type of inert waste produced by the construction industry a staggering 400 per cent, from $8 per ton to $40. The decision to increase the levy triggered widespread ire amongst members of the state's building industry.
The landfill levy varies by state within Australia, and in many places can impose an onerous economic burden upon construction businesses for their dumping practices. It currently stands at $52 per ton of solid waste in South Australia, around $58 per ton for both municipal and industrial waste in metropolitan and provincial parts of Victoria, and a hefty $120.90 per ton in metropolitan parts of NSW.
Queensland remains a major exception in Australia when it comes to landfill levies, having rescinded its $35 per ton landfill levy - a decision which has resulted in a 20 per cent increase in recycling.
Thankfully for both members of the construction sector and the environmentally minded, a broad array of methods already exist for both reducing the wastage and recycling any excess or unused building materials.
During the pre-construction phase, architects can incorporate features into the design of projects in order to greatly facilitate waste reduction.
These include sound dimensioning and designs that meet standard material sizes, as well as designing with an eye on eventual deconstruction, so that buildings can be easily dismantled and their components readily reused in the case of alteration or decommissioning in future.
During the estimating and procurement phase, construction managers can employ precise and careful planning to avoid over-estimates or the purchase of a needless surfeit of materials.
Once the stage of on-site construction is reached, key measures to prevent wastage include arranging for suppliers to deliver materials when they’re required, and sound storage measures to safeguard building materials from suffering incurring as a result of local climate conditions.
Recycling can be facilitated by the separation of disposed materials by means of clearly marked bins, and fully apprising all sub-contractors and workers of the separation and collection process.
In addition to helping the environment, recycling can bring significant economic benefit to building economies given the high cost of materials and the sheer plethora of material types are amenable to re-usage in various forms, including concrete, rock, metals, timber and plastic.
The measures outlined above are all easy and practical to implement, and do not involve the adoption of innovative or complex building techniques.
At the cutting edge of development in the building sector, however, are new methods and technologies that can also help greatly reduce materials wastage.
Chief amongst them is Building Information Modeling (BIM) – the software-based design and management paradigm that is sweeping the building and construction industries of many parts of the globe.
The use of BIM can enhance project management by providing accessible, data-embedded simulations of real-life construction sites that can be shared between stakeholders.
This in turn enables them to raise efficiencies and slash wastage via improved planning and heightened coordination between parties.
Prefabricated construction is another innovative building technology which can help to dramatically reduce wastage on building sites.
The transfer of construction activities from building sites themselves to off-site production facilities is considered one of the most effective waste minimization methods in the construction context.
The construction of modules in a factory greatly cuts down on the excessive procurement of materials, given that the amounts required for each prefabricated building unit can be precisely calculated long before they’re installed on site.
Off-site construction also dispenses with many of the difficulties involved in working on a building site which is exposed to the elements, where further wastage of materials can occur due to weather damage.