Construction Process - Environment
Many construction organisations have departments dedicated to environmental performance. Most site managers deal with environmental issues on a daily basis: for example ensuring waste is transported to a certified disposal site, protecting waterways and arranging for equipment to minimise air pollution. Lean construction techniques increase efficiencies in using all resources, such as time, energy and materials, and so have an impact across the criteria. Many of the criteria below are part of standard practice, ensuring compliance with regulation, with the Environment Agency playing a key role. For this section each of the criteria are explained separately, and two demonstrations are used to show fulfilment of the criteria overall.
Manage for minimum waste, using the waste EPI. Reuse waste on-site
The Quarry and Landfill Tax have resulted in alterations to site practice, as contractors and the supply chain find methods that save money. Pressure is added by planning and client requirements to retain all demolition waste and top soil, and increase the proportion of reused and recycled materials used. The waste EPI is a simple measure of performance. Other tools include SMARTStart and SMARTWaste.
Protect and enhance existing ecological features (trees, hedges, ponds etc.), using the biodiversity EPI
The local authority and Environment Agency have a role to play in this criteria: for example, ensuring plans for native planting are adhered to, Tree Protection Orders observed and water resources are protected. The biodiversity EPI provides a simple measure to assess performance, at design stage, during construction process, and when considering the finished product.
Minimise air pollution (dust and fumes) and noise pollution.
Air and dust pollution have a significant impact on site managers who control pollution, deal with regulatory officers and respond to complaints from the public. Recent guidance on air pollution provides best practice in control, and demonstrates the benefits of doing so. The Considerate Constructors Scheme rewards improved performance in noise and dust control.
Minimise water use during consturction and guard against pollution.
The construction industry accounts for the highest number of water pollution incidents. The Environment Agency provides a comprehensive source of guidance on the NetRegs website. CIRIA have published a 'Pollution Prevention in Construction' training pack and code of practice and Control of water pollution from construction sites: guidance for consultants and contractors.
Consider transport to and form site using the transport EPI. Consider energy use through plant and site services.
Transport of staff, materials and waste contributes significantly to carbon dioxide emissions, and deliveries and workforce car parking can seriously disturb the local community. The Considerate Constructors Scheme rewards site managers who plan car parking, ensure routes to site are well identified and keep deliveries out of rush hours or other sensitive times. Planning permissions are increasingly setting limits on how much road transport a construction site can produce. Congestion Charging is another pressure upon construction to manage its transport more effectively. Recent research on the transport EPI has refined the indicators and collected data on the costs of transport.
The Richard Doll Building (demonstration number 417) is a new cancer research centre for the University of Oxford. Nicholas Hare Architects, working in conjunction with the main contractor HBG Construction, are using this project as a vehicle to understand and better manage building waste to ensure that it is kept to a minimum.
At the pre-construction stage the architects placed emphasis on the following goals within their design process:
- construction materials were chosen with regard for their sustainable origins and their proximity to the site to reduce transportation;
- suppliers with a more enlightened approach to waste management and recycling were identified, specifying (where possible) those who encouraged this process;
- waste was designed out by methods such as modular design with regard to suppliers unit/sheet size, thereby reducing unusable off-cuts.
These very simple waste minimisation techniques, complement the more visible design features of the project such as naturally ventilated offices with exposed concrete soffits, solar shading to reduce heat-gain and highly insulated construction fabrics.
Building on experience from previous projects the contractor will be measuring and sorting waste in order to quantify and understand which portions of the works generate most waste. Sorting out waste helps to maximise the potential for these waste products to be recycled either by return to the supplier or for reuse by charities and other bodies.
Weston and Cronkinson Farm Primary Schools (demonstration number 336) were specified to use all six EPIs by Cheshire County Council. Operational energy and water and embodied energy were considered at design stage.
On site application of the waste, transport and biodiversity EPIs entailed some changes to site management. Waste contractor notes were used to estimate the volume of waste leaving the site. All vehicle movements to site were used to estimate the volume of waste leaving the recorded by the manager, allowing Willmott Dixon to assess how much transport is costing them and what actions they can undertake to improve performance on future sites. Weston School was sited in a maize field and scored 6/10 and 5/10 for impact during design and construction in the biodiversity EPI. Cronkinson Farm was delayed due to the late discovery of newts on the site. Since participating in the capture programme, the contractors have maintained and replanted a hedgerow and wild edge to the site, for wildlife and educational uses, as agreed with the head.