Potential Actions - Reducing Waste
There are two key areas for action to reduce waste on site during the construction process. Theses are Waste Minimisation and Waste Management. Please browse the below notes for information relating to these.
Waste Minimisation
Targeting the potential areas for waste generation in construction projects can help to significantly reduce the quantity of construction waste created. There are a range of opportunities to minimise waste before it is created and the earlier they are implemented within the project the greater the potential to significantly reduce waste.
Major improvements in materials efficiency are possible, without increasing cost, by minimising the overall creation of waste through the following:
Design Solutions – significant volumes of waste result from onsite cutting of materials to fit dimensional constraints of a project design. By considering wastage at an early stage in the process the design can be optimised for resource efficiency.
Material Procurement – the drive to reduce waste in construction projects is the responsibility of all involved. There is, however, a key role for contractors and subcontractors who procure and use materials. The efficient use of materials by contractors and subcontractors focuses on, effective estimating of waste, developing and implementing waste reduction solutions and producing accurate records of waste.
Construction Logistics – the cost of material wastage on a project not only relates to the material cost but also productivity losses associated with multiple handling of materials and inefficient construction practices that arise from poor logistics. Efficient logistics can have a substantial effect on minimising waste before it arises from the construction process.
Offsite Construction – offsite construction has a range of benefits compared to traditional build including the potential to greatly minimise on site waste. Through the substitution of a range of offsite construction methods there is the potential to reduce on site wastage by up to 90%.
Packaging – construction sites generate more packaging waste than any other waste stream. Steps to reduce the amount of packaging waste generated, coupled with greater re-use and recycling, result in significant cost and other benefits.
There are also opportunities for closed loop recycling to minimise waste in the following:
Demolition and Regeneration – maximising the recovery of materials and resources from demolition has economic as well as sustainability benefits. Minimising demolition arising through recycling and identifying reuse opportunities reduces disposal costs, material procurement and has the potential to create an income.
Utilities – an estimated 4.8 million tonnes per annum of materials are generated from water and gas asset renewal programmes throughout Great Britain. These works offer the opportunity for recycling and reuse of excavated materials in the reinstatement of trench openings.
The construction industry produces around 120 million tonnes of construction, demolition and excavation waste per year with only half of this currently being recycled or reclaimed. Waste management involves taking action to reduce the volume of construction waste being sent to landfill. Through the identification of potential waste streams, setting targets for the recovery of materials and the process to ensure that these targets are met a range of benefits can be achieved.
Construction clients and developers are increasingly looking to set targets and requirements for waste management and to move the industry from standard through to good and best practice in waste management. There are a range of tools and guidance available to help the industry meet changing policy and requirements, including the following:
· Achieving good practice Waste Minimisation and Management
· Site Waste Management Plans (SWMPs)
· The Code for Sustainable Homes
· Waste Recovery Quick Wins
Recycled Materials
Materials used in construction frequently cause some environmental pollution during their production. Quarries can damage landscapes, wood can come from unsustainable sources, metals use a lot of energy in production, PVC production produces atmospheric pollution, etc. Reclaimed materials and products made from recycled materials are likely to cause less environmental damage than new products and can also reduce refuse and land fill.
On-Site and Off-Site Recycling
The segregation of waste, on-site and off-site, can save waste going to landfill and enable companies to reuse and recycle more materials. Waste contractors can supply different skips which are colour-coded for specific types of waste (using the National Colour Coding scheme) or, alternatively, some offer a service of removing waste from site and then segregating it off-site at dedicated plants. There are also companies that provide ‘grinder’ or ‘mulching’ services to construction sites – they use machines that grind a variety of materials such as block, brick, gypsum, wood, trees, etc. The resultant ‘grinded’ materials can then be reused on site for a wide range of uses – and ‘bailing’ services which compress and bind plastics, corrugated card and paper materials.
Because there are more and more materials with recycled content coming on to the market it is possible to select recycled options for a very high proportion, or even for all of the materials required for new developments.
Some of the more common recycled materials and materials with a recycled content include the following:
Aggregates
Recycled and Secondary Aggreagtes (RSA) can be used in a range of construction materials. The opportunities for their use include the following:
Concrete – a common construction material consisting of coarse and fine aggregates mixed with cement and water. There are many different types, classes, specifications and uses for concrete.
Bituminous material is principally composed of coarse aggregate and fine aggregate filler; aggregates typically contribute 90-95% of the mass of bituminous material.
Hydraulically Bound materials (HBM) are simply materials which set and harden with the addition a binder material and water. HBM have potential to be used in a range of paving and non-paving applications.
Unbound materials collectively comprise a vast array of different materials, which may range in size from fine grains less than a millimetre in diameter up to stony material several centimetres in diameter.
Other materials that can be recycled included:
Plasterboard
Recycling Plasterboard
Approximately 3 million tonnes of plasterboard are used in construction in the UK each year. Detailed statistics on waste plasterboard arisings are currently scarce, but it is estimated that some 300,000 tonnes of waste plasterboard are generated each year from new construction activity (largely as offcuts). The amount of plasterboard waste arising from demolition and refurbishment projects is more difficult to quantify, but maybe in the range 500,000 tonnes to more than 1 million tones per year.
Wood
Recycling Wood
Recycled wood products are made from post-consumer and post-industrial sources. Wood waste is cleaned and processed to remove any contaminants and to reduce particle size. This material is then used to manufacture a range of quality products for different markets. Some products may be made entirely from waste wood or they may contain a proportion of virgin material.
Glass
Recycling Glass
Recycled glass is a hard, inert material which can be used in many different ways. The most popular and environmentally favourable approach is to remelt it to produce more glass, a process which can be repeated over and over again. This not only saves valuable natural resources but also saves energy and reduces emissions of carbon dioxide.
Plastics
Recycling Plastics
Recycling plastic into end applications that displace virgin plastics can save on average two tonnes of CO2 for every tonne of plastic recycled. There is a wide range of markets for them and increasingly these include full closed loop recycling back into packaging.