How does the construction industry effect on environment?

Answer 1

The construction process and building use not only consume the most energy of all sectors in the UK and create the most CO2 emissions, they also create the most waste, use most non-energy related resources, and are responsible for the most pollution.

Climate Change

Building use in the UK contributes about 50% of the UK's CO2 emissions and construction contributes about another 7%. The AECB have shown that the Government figures on energy performance of houses grossly underestimate the CO2 gains that could be made by building energy efficient buildings. The main base performance criteria for energy efficient buildings all concern the thermal performance of the building shell where most of the CO2 gains can be most easily made.

The fact is that if we are serious about climate change then we need to stop playing games with technologies which do not deliver real CO2 savings. The real challenge in this area is the refurbishment of existing buildings. However it would help for a start, if we also produced really energy efficient new buildings.

Waste

According to DEFRA the waste going to landfill from the construction industry in 2004 was about 100 million tonnes. This is more than 3 times the amount of domestic waste collection (28 million tonnes). It has gone up from about 70 million tonnes in 2000. In many situations this is equivalent to one house being buried in the ground for every 3 built. This is an important consideration when the embodied energy of a building is being calculated. Usually such calculations do not take into account an extra 25% energy for waste. This is obviously more serious for higher embodied energy products than low embodied energy products.

There are increasing regulations about waste disposal from construction and many products, even common products like gypsum plasterboard and mineral wool insulation are now labelled as hazardous and require special disposal. In addition there are many projects to find new uses for waste construction materials (through Government bodies such as WRAP). However here, as with waste disposal, the less processed a material is, and the less hazardous, the easier re-use, recycling or healthy disposal (for example through composting) will be.

Resource Use

The construction industry is the major consumer of resources of all industries in the UK. It accounts for 90% of all non-fuel mineral use, and a large proportion of timber use. Many of the materials used in the UK now come from abroad, sometimes from countries where with less environmental control or labour justice.

As BioRegional and the World Wide Fund for Nature have shown in their One Planet Living material , if everyone in the world consumed resources at the same rate as we do in the UK it would take the equivalent of 3 planets now to sustain this consumption. As a global community we exceeded sustainable levels of consumption in the mid 1980s, so both from the point of view of human survival and of justice and equity, it is not feasible or desirable to continue at current levels of consumption. It is not possible for the way of consumption in the UK to be spread throughout the globe, and as a matter of urgency we and other western nations need to radically reduce our consumption of resources.

A distinction needs to be made between sustainable and non- sustainable resources. Sustainable can be divided into renewable resources (those which can be renewed - particularly those that are grown in short time cycles such as food and certain kinds of timber) and plentiful resources (such as clay, chalk, and sand). In addition materials which can be indefinitely re-used (or recycled easily) are to some extent sustainable. Non-sustainable resources are those of which there is a known limited supply, and which cannot be replaced or easily reused or recycled with minimal extra energy input. These non-sustainable resources therefore include many minerals, oil and some timber (which is very slow growing or where the extraction causes the extinction of the habitat and therefore of the resource) at our current levels and forms of use. In the UK the construction industry is the main consumer of non-renewable resources, as well as a huge consumer of renewable resources, and this means it must bear greatest responsibility for addressing this situation, and addressing it quickly.

Habitat Destruction

While the three greatest and most imminent threats to the survival of our civilisation are global warming, peak oil (the growing energy gap between supply and demand) and resource depletion, habitat destruction can have a more immediate and disastrous effect on certain localised areas and species. Sometimes these can also have a global impact (for example the impact of the deforestation of the Amazon rain forests).

It is hard to keep track of the number of species made extinct every year, and of the further erosion of biodiverse and rare habitats. It is equally hard to relate this destruction to construction use in the UK. However the fact that the construction industry is such a huge consumer of materials, particularly of imported chemicals, minerals, metals and organic materials such as timber, inevitably means it has a huge impact and obviously has the greatest impact of any sector in the UK, on habitat erosion and destruction globally.

Many essential materials are now in short supply. These include materials such as copper, which is largely mined in South America where whole mountains have been taken down and landscapes altered in the search for ever more rare resources. They include materials like Titanium Ore which is used for the production of Titanium Dioxide, which is one of the main ingredients of paint among other things. This is often mined in rare habitats such as Madagascar with consequential and inevitable dangers to the ecology .

Of course it is possible to mine and extract materials from habitats without destroying them. However there will always be consequences to this benign form of extraction in terms of cost, speed and quantity. It is therefore imperative that we radically reduce our demand on such materials in order to allow this process to happen benignly. At present the whole world is heading in the opposite direction, and we will lose huge areas of unique habitat forever in the coming years unless we change the way we consume such materials. This is particularly as regards how we build. It means using less of these materials by building more simply, with more local and plentiful (ie sustainable and renewable) materials and with less waste.

Pollution

Finally the environmental impact of construction is also felt in terms of pollution. This is not in the extraction but in the processing of materials for construction. And again, not surprisingly, the construction industry has the biggest effect of all sector because of the quantity of materials used in construction

In the past there was a simple general equation between the amount of pollution and the amount of energy in a process. On the whole the more energy required, and the more processes, the more waste and the more pollution was generated. Processes such as the processing of plastics for PVC, PU and PI, the manufacture of Titanium Dioxide, the galvanising of metals were all very polluting. Much of this is now controlled by legislation and pollution of air, land and sea within the European Union and many Western Nations is now reducing. However we have also exported a lot of our pollution in the outsourcing of our manufacturing to non- western nations such as China, India, and areas of South East Asia and South America. Products may be assembled in the West, but most of the basic materials and components are often processed elsewhere. The loss of control of manufacturing processes therefore has a considerable environmental impact.

As with habitat destruction, it is difficult to track this or control it. Assessments like BREEAM attempt to assess this effect but there is a huge lack of data and resource for doing it across all product lines. What we can do is reduce high energy material use, and use local and low energy materials as much as possible. Until there is proper global control of polluting processes or a clear legislation/ incentives in the UK along with proper assessment lifecycle assessment of all materials and manufacturers, we will have to stick to what we are sure of, and also what is inherently non-polluting.