Design - Environmental
The operation of buildings accounts for one of the most significant environmental impacts of the UK. Design of new build and refurbishment projects can improve building environmental performance in many ways. Thoughtful design that involves members of the supply chain can also promote efficiency on the construction site.
Design for minimum waste of materials. Provide facilities for the minimisation and management of waste.
Lean construction provides a variety of proven methods for reducing waste at the design stage: standardisation, off-site construction, and using modular components can all help to minimise waste of materials. Provision for operational site management can also be considered in the design, such as providing space and facilities for building users to reduce, reuse and recycle waste. For example, BREEAM rewards specifications that allow for internal and external storage and services for the building users to recycle waste.
Off-site construction has featured strongly among the demonstrations. Approximately 40% of the housing demonstrations are using some element of off-site construction. These projects account for about 25% of the total value of the housing demonstrations, but have produced roughly 70% of the number of units. This indicates how much less wasteful these methods are. The Housing Forum has published a commentary on the use of off-site fabrication.
The Great Western Hospital Relocation (demonstration number 124) is an excellent example of waste management being considered from the original design concept. The project was a pathfinder project for the implementation of the Natural Step, an environmental initiative to work towards sustainable development. This meant all partners were encouraged to undertake a strategic review of their actions.
Carillion partnered with the wall panel supplier to create a bespoke product, saving approximately £285,000 in time and material waste. The panel supplier agreed to take back and recycle off-cuts.
Similarly a standard ceiling tile size was specified for the entire hospital, saving waste of materials. Off-site construction resulted in no scaffolding being required on site, saved waste and also reduced the risk of accidents. The Hospital introduced a range of innovations and measured their financial impact, which is featured in an accounting report.
Protect and enhance biodiversity using the biodiversity EPI. Ensure natural features can be easily managed and maintained.
The planning section of the checklist focuses on the footprint of the building and how this impacts on the biodiversity on the site. This section highlights the steps that need to be taken in considering the landscape and building design once the footprint has been decided. Building elements can be used to encourage bird and bat populations, and 'green' roofs provide excellent habitats for insects. Ponds, hedgerows, grassland, and heathland are all examples of landscape features that should be protected and can be enhanced through good design. Developers and designers can better understand national and local biodiversity priorities through the UK BAP and associated local plans.
The Association of Wildlife Trust Consultancies and the Institute of Ecology and Environmental Management are useful contacts to go beyond legislation and make the most out of existing and potential biodiversity. Integrating the building and landscape design will minimise overlap and improve team communication, producing a better quality design. Users and maintenance must be considered in the design for it to meet requirements and whole life costs. The biodiversity EPI considers steps taken at design and construction stage.
The Christchurch Junior School Replacement (demonstration number 165) made reference to the UK BAP in their external works. A diverse range of plants were used for structural planting and ornamental areas, including many native species which have increased the planting around the perimeter of the school site not only enhances the ecological diversity on the site but enhances the appearance and provides shade and shelter for pupils and staff. The landscaped areas are designed to require low levels of maintenance in the future. The playing field is self draining through natural percolation thus avoiding the need for biodiversity on the site and will attract and encourage wildlife. Native tree and shrub maintenance of a land drainage system. Bark mulch for planting areas and peat free planting composts were used from Eco Composting in Christchurch, a local recycling centre for green waste. All this and more was achieved on a tightly limited budget.
Specify local and low environmental impact materials (e.g. use A-rate specifications from the Green Guide or equivalend and timber form certified well-managed forests). Use the embodied energy EPI.
There are many reasons for choosing local and low impact materials. Local suppliers can be cheaper and provide specifications that fit the local vernacular. Less transport will reduce costs and benefit the local community and environment. Reusing and recycling materials on site, and purchasing materials with a high recycled content, will have a similar result, as well as saving on the Aggregate Levy and Landfill Tax.
The embodied impact of materials has been widely researched. The use of novel materials such as sheep's wool and recycled paper insulation is increasing. The impacts of traditional specifications like mineral wool have been measured and compared (for example in The Green Guide to Specification). Energy use and pollution during the production of materials is important, but most natural materials are also likely to be less detrimental to the health of tradespeople and building users. Finishes and fittings are often replaced, and synthetic versions can have significant impacts compared to more natural specifications. For example painters suffer a 40% higher lung cancer rate than average.
Timber is widely acclaimed as one of the best natural building products. Due to increasing concern about forestry practices around the world, many certification systems now exist to monitor and certify the timber supply chain. The Forest Stewardship Council (FSC) is a well-recognised independent and international standard. Central government has specified FSC timber for some years and now local authorities are following suit in their procurement policies.
The New Architectural and Planning Studios at the University of West of England (demonstration number 354) focussed on the embodied impact of materials. Amongst many innovations, agricultural straw bales, readily available from the local area, were used in structural steel walling elements to take advantage of their insulation properties. The bales were assembled into large panels off site and brought to site to receive final finishing.
Fairfax House in Lambeth (demonstration number 370) is the first construction project in Britain to be independently certified by the FSC for its use of sustainable timber. This means that not only can the project claim to use timber from well-managed sources, but that an independently verified chain of custody exists between the timber used in the building and the forest it came from. This chain of custody proves that the construction project is using timber in a sustainable way. The project used FSC tropical hardwoods as well as European softwoods.
The FSC content, including the frame, cladding and second fix items, is estimated to be 70%. The residents are proud that their homes have contributed towards the global sustainability of forests.
The hemp houses at Haverhill (demonstration number 1021) compared traditional brick and block construction with hemp and lime houses on a small housing development. The extremely low-energy material production process uses hemp stalks, which are usually a waste material.
The hemp homes performed as well as the traditional in thermal, acoustic, durability and permeability tests. Hemp homes require less excavation and the breathing quality of the walls means less condensation and generally a warmer and drier internal environment.
The East Dorset Housing Association (demonstration number 1044) took materials specification seriously. Units were constructed using a Swedish system of large timber frame closed panels complete with windows and doors. The panels are highly insulated, ecologically sound, able to be erected very quickly and are of excellent quality. For example, the pre-finished, triple glazed timber windows are guaranteed not to need repainting for 30 years. The roof manufacturer and roof light manufacturer worked together to enable the roof lights to be fixed using less timber cuts and waste. Waste was halved compared to traditional sites early in the demonstration, and further reductions were achieved on later sites. The need for quarry products was reduced, no materials containing gypsum or toxic products were used, low smoke zero halogen cables were installed and soil pipes were specified that were manufactured from recycled plastic. Many steps were taken to choose low-toxicity paint and other building materials, resulting in healthier homes. More details are available.
Optimise passive energy use (e.g. solar gain). Minimise energy use (e.g. lighting, heating/cooling, ventilation, insulation). Consider CHP and renewable energy sources. Use the operational energy EPI. Fit sub-metering and intelligent building monitoring systems.
Building operation accounts for 40-50% of energy consumed in the UK. The government has taken many actions to control energy use, through the Climate Change Levy, revision to Part L of the Buildings Regulations and providing grants for renewable energy. The Climate Change Levy charges all commercial energy users for fuel use. The new Part L sets more stringent energy efficiency standards for new build and refurbishment of domestic and commercial properties. The EU Directive on energy labelling of buildings was published in January 2003. The government has three years to implement it. Likely changes are: Part L revisions will apply to the whole building when refurbishment and extensions take place above the floor area threshold, energy labels will be produced for all buildings at point of sale or change of tenancy and plant inspections will become more strict.
There are many possible solutions to reduce fossil fuel use. Many sources of guidance and grants are available to help you choose, design and install the right system, such as Action Energy and Clear Skies.
General actions will include:
- using passive gain and loss where possible, such as natural light, air movement, thermal mass, temperature gradients and other natural phenomena;
- when passive solutions are constrained or do not fulfil requirements, minimise the energy use of the mechanical systems installed;
- consider what renewable energy sources are available, such as solar water heating, wind turbines, biomass and photovoltaics;
- ensure monitoring of thermal performance and energy use is in place, and the building is as responsive and easy to use as possible.
Such actions may reduce capital cost, should reduce operational costs and will lead to a more comfortable healthy internal environment. A range of demonstrations have considered all or some of these areas. One of the earliest demonstrations was a new facility building for the Environment Agency (demonstration number 4). The glazing and innovative external solar shading was a low cost solution that resulted in good energy efficiency and thermal performance, despite teething problems in the system.
Great Notley Country Park Discovery Centre (demonstration number 108) provides a sports centre, an environmental education facility, and a social community resource.
The design incorporates a number of innovative ideas to reduce energy consumption, generate energy, recycle waste products and minimise environmental degradation. It is hoped that the site will be a net producer of energy rather than a consumer of it. The building has been insulated to a high standard and has a Termodeck heating and cooling system integrated with the building structure, which integrated with the building structure, which ensures good controlled ventilation. The centre is equipped with a 6kW wind turbine generator, coupled to a grid connection. There are solar roof panels to reduce energy consumption by heating water for showers.
Specify flexible information and communication services.
Flexible information and communication services allow the users of a building to adapt their working and leisure patterns to suit themselves rather than the constraints of the building. It can allow greater remote working, reducing the need to travel, and increasing the productive use of space. New high-performance commercial and domestic developments often make a selling point of the "future proof" and flexible nature of the information and communication provision. To encourage home working and more flexible use of commercial space, such specifications need to become standard in new build and refurbishment.
At Primrose Field in Harlow (demonstration number 1024) Swan HA worked with Integer to convert the standard Integer housing brief into one for social housing. One of the features of the Integer system that Swan included was the provision of an intelligent cabling system. Cables were put in place for communications (phone, fax and internet), entertainment (terrestrial TV, radio, cable TV and internet) and data (computer and internet). Removable cornices allow the main cables to be easily accessed for future upgrading, and a service void behind the internal plaster board allows extra sockets and switches to be placed easily. The door entry system is linked to tenants' phones and TVs, ensuring ease of use and improved security. These measures reduce maintenance costs for the association, and provide improved social opportunities, skills development and homeworking options for the tenants.
Ensure high indoor air quality through effective ventilation, and specifying materials, finishes and cleaning products with minimal harmful efffects.
People in the UK typically spend about 90% of their time indoors, so the quality of the indoor environment matters. Poor indoor air quality (IAQ) can have a significant adverse effect on health (from sick building syndrome to asthma and cancer), comfort and productivity. IAQ problems can have various economic consequences at personal, organisational and national level, including costs directly due to treating health problems:
- absenteeism and reduced worker performance;
- increased staff turnover;
- damage to relations between landlords and tenants or between employers and employees, and the time taken to deal with complaints;
- legal liability;
- devaluation of a building or company;
- deterioration of furnishings, equipment, and building fabric.
Indoor air pollutants arise from a wide range of sources, including people and their activities, equipment and building services, building and furnishing materials, the outdoor air, water and soil. From these sources come pollutants that may be:
- biological (such as viruses, bacteria, fungal spores, mites and their metabolic products);
- inorganic (for example radon, carbon dioxide, carbon monoxide and nitrogen oxides);
- particles or fibres;
- formaldehyde and other volatile organic compounds (VOCs);
- complex mixtures such as environmental tobacco smoke.
Achieving good IAQ is not just a matter of meeting standard ventilation requirements; the first choice for reducing indoor pollution should be source control wherever possible. For example, substitution of products or processes, pre-treatment of materials, or isolation of sources will reduce pollution. Therefore, to avoid IAQ problems, it is important to understand the sources of indoor air pollution, the pollutants produced by these sources and their likely health effects. Source control requires attention both to new materials and components and to the promotion of good maintenance and cleaning. Where source control is not a viable complete solution, consider ventilation close to the source, more efficient general room ventilation, control of ventilation by the building users and air cleaning, not just a higher ventilation rate.
The new Docklands campus for the University of East London (demonstration number 49) used several innovations. With the brief emphasising the requirement for a lowmaintenance, low-energy building, resistant to external noise, the design team focused upon reducing the big energy consumers of heating, cooling and ventilation. This led to the architect, Edward Cullinan Architects, specifying Termodeck, a hollow precast concrete ceiling plank through which tempered air is supplied. As Termodeck requires a sealed and insulated building, it also helps to cut out noise and outdoor pollution. The system does not recirculate air - eliminating one potential cause of sick building syndrome. As the solution demands an exposed structure, the installation and maintenance of finishes - a source of indoor pollutants - is reduced.
Specify zero ozone depletion and low Nox systems and materials.
Buildings can contain high levels of ozone depleting substances in the air conditioning system and insulation. A passive approach to heating and cooling buildings will therefore also help you to reduce the damage done to the ozone layer. It is easy to specify materials in the roof, wall and floor components, as well as the boiler insulation, that do not contain ozone depleting chemicals.
For example the following list inherently have zero ozone depletion potential:
- mineral fibre (e.g. Rockwool);
- glass fibre (e.g. Owens Corning);
- cork (e.g. Korklite);
- cellular glass (e.g. Foamglas);
- expanded polystyrene beads;
- nitrile rubber (pipework insulator);
- cellulose (e.g. Warmcell).
A significant group of ozone depleting chemicals are Hydro-Chloro Fluorocarbons (HCFCs), which are now banned for use in the manufacture of insulation. They are only allowed for Specify depletion systems on site use until January 2004. HCFCs can still be used as refrigerants, but will be phased out by approximately 2010.
Nitrogen oxides, commonly referred to as NOx, contribute towards global warming and acid rain, and react with oxygen to produce ozone, which is a pollutant at ground level. They arise from burning fossil fuels, so reducing consumption of these will reduce NOx emissions. Energy from renewable resources (except the combustion of biomass) does not produce any NOx. It is also possible to specify low NOx burners in boilers, which run more efficiently and have lower emissions.
It has not been possible to identify a demonstration for this criteria, as data has not been recorded for it, but a number of the demonstrations have achieved it through avoiding air conditioning and careful materials specification.
Ensure fitting are low water volume. Consider rainwater and grey water recycling. Consider permeable design for hard landscaping. Use the water EPI. Fit sub-metering.
As more dwellings and commercial buildings have water meters, and the costs of treating water increase, reducing water use becomes more of a concern. Water consumption can be easily reduced by specifying fittings such as dual flush toilets, spray taps and efficient white goods. These can all be achieved at little or no extra cost, and bring immediate cost savings in use. The Department for Environment Food and Rural Affairs (DEFRA) and the Environment Agency maintain a database of water saving research and initiatives. The water EPI provides a methodology and benchmark for designers interested in operational efficiency.
For new build projects, rain water collection for toilet flushing can have other benefits through awareness raising and reducing peak demand on drainage and waste water services. Currently, water use exceeds supply only in the East of England, but this may change with predicted climate change and the costs of water treatment will increase with time.
Sustainable urban drainage systems (SUDS) are the subject of extensive research and guidance from CIRIA, the Environment Agency and Scottish Environment Protection Agency for example. It has been demonstrated that permeable products and related systems can have significantly lower maintenance costs than traditional solutions, reduce pressure on existing drains and help to replenish aquifers.
The Hotels Water Efficiency project (demonstration number 368) managed by the Mandix Consultancy in Cardiff, is an unusual demonstration. It has focussed on adding value for the client by helping them to control their operating costs, improve their service levels and raise their environmental performance through the installation of water efficiency devices. The project monitored hotels for one year, guided the installation of water efficiency measures, and then monitored usage for a further year. Monitoring was carried out by the Centre for the Built Environment at Cardiff University. The hotels have decreased their water use by 14-53% per guest per year: this is saving them £5-24 per guest per year. This project has been supported by the Environment Agency, The BOC Foundation, Corus Group plc, Wales Tourist Board, Envirowise, Mandix, HCIMA, water undertakers in Wales, Green Globe 21, Plumb Centres Ltd, installers and manufacturers.
The Henry Box development near Witney in Oxfordshire (demonstration number 293) had to provide an affordable housing solution to being in the middle of a flood plain. The site is relatively flat with minimal fall to outlet available.
It uses a narrow shallow combined kerb drainage system to allow for achievement of a sustainable drainage system. Positive drainage such as the kerb drains and storage facilities work alongside passive drainage such as soil absorption and swales, leading to an efficient and sustainable facility.
Discourage single-occupant car use through public transport and cycling provision, making the development safe and secure, and providing showers and changing rooms.
The energy used to transport people to an office building can be equal to the energy used within it. Providing facilities to encourage modes of transport such as cycling and walking will have many benefits such as reduced car parking costs (providing car parking can cost as much as £800 per space) and a healthier workforce. Partnerships with infrastructure and public transport providers will be necessary for larger developments. Many local authorities and private companies have produced Green Transport Plans, and enjoy the benefits described above. For new build, providing facilities for public transport users will help towards BREEAM and EcoHomes ratings.
Beddington Zero Energy Development (BedZED - demonstration number 1016) is a mixed housing and commercial development of 82, one to four bedroom flats and houses, with 1600m2 of work space.
BedZED is a Peabody development in partnership with BioRegional Development Group, designed by Bill Dunster Architects.
As part of the planning permission, BedZED needed a legally binding green transport plan. The three-point transport strategy aims to: reduce the need to travel, promote public transport and offer alternatives to using private cars. BedZED's target is a 50% reduction in fossil-fuel consumption by private car use over the next ten years compared with a conventional development.
There is the chance to live and work on site, plus a sports facility and car pool. Other planned facilities include a café, clubhouse and premises for a local children's nursery. These additional facilities have successfully embedded a strong community spirit and also play a part in reducing the need to travel. BedZED enjoys good transport links, travel. BedZED enjoys good transport links, served by train, tram and bus routes. Design issues have included:
- drop-off points for deliveries;
- generous bike storage;
- links into Sutton's existing cycle network;
- a pedestrian first policy, with good lighting, drop kerbs for prams and wheelchairs and a road layout that keeps vehicles to walking speed.
Consider ease of operation and maintenance through commissioning time and documentation.
BSRIA, BRE, CIBSE and HVCA carry a wealth of information on effective commissioning. A recent publication provides a protocol for handover of office building operations. A poorly commissioned building is likely to consume far more resources and have a poor internal environment compared to a properly commissioned project. Poor handover is often due to ill-defined responsibilities and time constraints towards the end of projects.
Design team professionals are in an ideal position to ensure documentation and commissioning is effective and robust. Designers also have vital role to play in making the building as straightforward to use as possible, removing the need for lengthy documentation. If a designer has gone to the trouble of installing features such as low environmental impact materials, documentation should advise future managers of what should be specified in maintenance and refurbishment.
For demonstrations, successful commissioning is a key consideration in ensuring client satisfaction and many partnered teams remain in touch with the building users after completion. Many housing demonstrations involve monitoring of tenant satisfaction and living costs for an initial period.
Gusto Construction's award-winning Millennium Green development (demonstration number 1063) at Collingham embraces environmental good practice and sustainable development objectives, combined with traditional ideals and common sense.
The properties use up to 60% less energy than a standard new house through the use of solar panels, rainwater recycling, heat recovery ventilation systems and high levels of insulation. Additional benefits including high-performance timber windows, grade A electrical appliances, central vacuuming system and ISDN compatible telephone and internet connections throughout, give homeowners the opportunity to enjoy a better quality of life. Gusto provides all homeowners with an information pack, explaining the various features of the houses, and how to use the house efficiently.
Consider daylighting, ventilation humidification, personal control and space for wee-being and comfort. The DQI considers a range of environmental criteria.
Studies of good design and daylighting in educational buildings show academic achievement improves 5-20% with improved standards. Similar findings also apply to comfort in dwellings, recovery rates in healthcare buildings and productivity in commercial buildings.
Comfort often relates to the degree of control and understanding an individual has of their environment. Many demonstrations have featured buildings with high-quality indoor environments.
The Great Notley (now Notley Green) Primary School (demonstration number 115) was designed and built by an innovative team appointed in April 1997 by Essex County Council and the Design Council.
A commitment to devising a new approach to brief development formed the starting point for a tracking process. The end product was an interactive sustainable learning environment built within standard budgets, featuring breathing walls, good daylighting, oriented to maximise solar gain but not to overheat in summer, with a responsive underfloor heating system. The building services gained the Building Services innovation award in 2000.
Gallions Housing Association's Ecopark development in Thamesmead (demonstration number 1115) uses a combination of sustainable features through a selection of 39 houses.
A detailed monitoring and evaluation strategy to review the success and practicality of the features incorporated within the scheme is being undertaken and will help to focus the Associations future development strategy. Some of the technologies incorporated in the scheme are to maximise solar gain as well as improve well-being and comfort: super-insulating windows, passive ventilation, underfloor heating and integral sun spaces (similar in style to a conservatory). An on site visitors' centre is open to showcase the development to other registered social landlords, members of the development and construction industries, school children, the media and interested members of the public.
Design for flexibility or deconstruction with minimum waste.
With most buildings expected to last at least 60 years, and considering the changing needs of society, many buildings may need to alter use during their lifetime. Once refurbishment is no longer an option, buildings need to be deconstructed, creating the minimum of waste. Ease of deconstruction allows more value to be extracted from the building.
Off-site construction is a key method that allows for flexibility in layout, location and deconstruction. Lifetime housing needs to cater for the needs of single occupants, young families and the elderly. In other building types, flexibility is of commercial importance, for example in offices and laboratories.
The Dorman Museum (demonstration number 216) was Phase One of the museum extension. The end elevation was contracted entirely of proprietary systems to be suitable for demounting and re-erection for possible future extensions.
Since then Phase Two of the project has used this feature, successfully removing the façade, building an extension and reassembling the façade. This was the optimum solution in terms of construction cost and time.
The housing demonstrations have featured various innovations. At White Rock Court in Liverpool ( demonstration number 1003) a panel system was used to allow flexibility in internal layout as no internal walls are load-bearing.
The Central Oakridge Regeneration in Basingstoke (demonstration number 1122) has proved a regeneration scheme with a difference. In consultation with the local community, the project has involved a large element of off-site construction and pre-assembly.
Some of the units feature the flexibility to expand into the loft space or via sideways extensions. This helps to fulfil the commitment to lifetime homes.