The construction industry produces high levels of waste and is a major contributor to solid landfill. While it could be argued that waste is a natural part of the construction process, there is also opportunity for improvement. In this article we research and identify three methods, solutions or approaches that could be applied to residential construction to reduce waste. Examples are provided of successful application in construction to support each case.
In Western Australia, the State Government introduced a policy called the ‘State Waste Strategy’ which sets targets for the reduction of construction and demolition waste to landfill. The target was to divert 75% of construction waste from landfill by 2020, At the time of writing this report, results of this aspiration were not readily available, however below are some of the initiatives encouraged by the policy.
By far the best time to start thinking about waste management during the construction phase of a project is during the planning phase. An understanding of the excess materials that are likely to be generated and the methods that can be adopted to keep waste materials from ending up in landfill.
This can be formalised by developing a Construction Waste Management Plan. If adopted, it should focus on these three keys objectives;
Mininmising the amount of waste generated by the construction works.
Maximising the amount of waste which can be recycled or reused.
Mininmising the amount of material sent to landfill.
To realise the objectives above the following elements of the construction process should be addressed;
Where is the sources of waste materials and how much waste is likely to be generated?
Are there alternative methods to generating the waste identified above?
Engage a waste management contractor.
Make sure there are adequate provisions on site, such as recycle bins and waste collections.
Assign responsibilities for waste management to key personnel, such as the main contractor and sub-contractors.
Monitor implemented measures to ensure they are being properly undertaken and the results of the measures in terms of reduction of waste. (Walga 2021)
Design can make the most of spaces and materials resulting in efficient buildings that generate less waste.
Careful consideration of every aspect of the design can minimise material use such as;
Efficient structural design using less material for the same performance.
Detailed calculation of Mechanical, Electrical & Plumbing (MEP) system to avoid over sizing and excessive friction in pipes which reduces energy and materials.
Multi-function spaces and materials such as operable walls and structural elements that do not need finishes.
Greater accuracy in design also results in less waste. The use of Building Information Modelling (BIM) means that the building and all its component parts can be accurately modelled which results in fewer coordination issues and accurate procurement of materials.
Designing for easy replacement of component parts can avoid damage to materials they are fixed or adjacent to. For instance, wall mounted WCs are completely separate to the floor and so can be replaced without any damage to floor tiles or finishes or all and floor finishes that are fixed that allow removal without damaging the floor or wall they are fixed to.
Modular construction involves constructing elements within factory conditions such as toilet pods or residential units. By utilising factory conditions means mass producing identical components to strict tolerances. This produces far less waste than insitu fabrication on site. (Construction & Demolition Waste Best Practice Strategies - Zero Waste, 2021)
Reclaimed components or materials offer significant savings as well as the benefits of waste reduction but can be hard to source to match the specific requirements of a project.
Reclaimed bricks are a common and offer a vintage look that is often sought after.
Other possibilities for the use of reclaimed or reusable materials are;
Excavated material from the site for cut and fill to achieve desired site levels.
Recycled timber – old railway sleepers are sought after, especially for landscape works.
Organic materials such as hemp for wall construction which also has great thermal, fire and acoustic performance.
As well as materials, components and systems can be re-used particularly if they are from the same use, such as commercial office fit outs. Other consideration include;
Raised floor or partition systems.
Furniture.
Doors.
Carpet.
Ceiling tiles or maintain the grid with new tiles.
The more local the reclaimed material is the better to avoid transport and the carbon emissions associated with this.
(Construction & Demolition Waste Best Practice Strategies - Zero Waste, 2021)
References
Wastenet.net.au. 2021. [online] Available at: <https://www.wastenet.net.au/profiles/wastenet/assets/clientdata/document-centre/wal2708_construction_waste_a4_v2_singles.pdf> [Accessed 5 May 2021].
Zerowastedesign.org. 2021. Construction & Demolition Waste Best Practice Strategies - Zero Waste. [online] Available at: <https://www.zerowastedesign.org/02-building-design/fa-construction-demolition-waste-best-practice-strategies/> [Accessed 5 May 2021].