The main environmental impacts of construction are shown below and it is in these areas that improvements can most easily be achieved:
- Site assessment, contaminated brown field site use, remediation and development,
- Ecological damage and waste minimisation during construction,
- Site design to maximise passive solar, hydrological, ecological and other features,
- Selection of sustainable and low impact materials
- Integrated design of site, building structure, insulation, lighting, HVAC systems etc. to minimise running costs, heat losses and energy use,
- Consideration of the environmental impacts of buildings throughout their life and continued facilities management to minimise them.
Over the standard sixty year design life of a building, the operational and maintenance costs are around six times as much as the initial build costs.
Proper management of all aspects of building design, construction and use can dramatically reduce the overall cost of a building throughout its life, and need not even cost more at the design and building stages. Sustainable Construction improves the performance of building projects at every stage, both in financial and environmental terms.
Sustainable design considerations
The items listed below provide a basic insight into some of the available possibilities for energy saving and the use of environmentally friendly and sustainable materials and products in building projects.
External building design
- Orientate buildings and terraces so that principle rooms capture maximum solar radiation (ideally within 30 degrees of south)
- Shelter surfaces from the cooling effects of the wind e.g. landscaping using native species in direction of the prevailing wind
- Incorporate rainwater butts in downpipes and use permeable surfaces around buildings
- Use vitrified clay pipes which have a less harmful production process than PVC and can be recycled at a later date. PVC is less easily disposed of.
- Use recycled or new concrete slabs rather than asphalt paving
The building fabric
- Use recycled materials - second hand bricks/tiles/slates, crushed concrete hardcore etc.
- Increase insulation beyond the minimum requirements of the Building Regulations in walls roof and floors
- Mineral wool and expanded polystyrene insulation uses less production energy and produces less noxious emissions than extruded polystyrene and polyurethane
- Softwood timber frame construction requires less material than traditional construction
- Use timber windows and doors rather than UPVC
- Use high quality untreated softwood rather than hardwood for doors and windows (preferably one with a Forest Stewardship certification)
- Use European softwoods from a renewable source rather than hardwoods
- Use argon filled double glazing which has a lower emissivity for less heat loss
- Waterbased or natural paints and stains will not threaten the painter's health or the quality of the air
- Use draft excluders to reduce heat loss through doors and windows
- Use local materials that do not have to be transported long distances
- Use condensing boilers
- Lag existing hot water tanks and pipes
- Install dual flush WCs
- Provide solar energy panels for water heating
- Install temperature controls for different parts of the house e.g. thermostatic valves
- Use low energy lighting
- Install whole house ventilation systems with heat recovery units
- Do not extend heating into a conservatory
- Consider installing a greywater recycling system