Critical Review of Data for Environmental Impacts of Household Activities: Executive Summary Report

A research report completed for the Department for Environment, Food and Rural Affairs by The Centre for Business Relationships Accountability, Sustainability and Society.

June 2006
Summary Review of Data for Environmental Impacts of Household Activities

1. Introduction: Background to the Report

The significance of household consumption in the UK goes far beyond its economic value. Socially, household consumption provides us with sources of satisfaction, ways to express our identity, and contributes to the cultural life of the nation. Household consumption also accounts for a considerable proportion of the environmental impacts generated by our way of life and our economy.

To develop a more sustainable society, changes to regulations, production technologies, business practices and government policies will all be important. It will also require changes to the purchasing and consuming behaviour of UK households. Understanding the significance of household consumption in terms of environmental impacts, and developing strategies to reduce these impacts, are major challenges for policy makers. To meet these challenges, they need to have relevant and reliable evidence on which strategies and decisions can be based.

This report provides a distillation of the key findings of the Critical Review of Data for Environmental Impacts of Household Activities conducted for Defra by the Centre for Business Relationships, Accountability, Sustainability and Society (BRASS), based at Cardiff University. This project sought to identify and review a range of the most useful on-line and in-print data sets, reports, papers and other sources relating to the environmental impacts of household consumption. The aims of this exercise were

(a)to provide a comprehensive and critically evaluated summary of available data sets and resources on key components of household consumption that may be used as evidence in future decision making;

(b)to highlight those areas where there is currently a lack of reliable and accessible information, which could usefully become the focus of future research initiatives.

In total the BRASS research team identified a wide range of sources and evaluated more than 300 of them. To identify the most useful sources, each was evaluated in terms of :

  • the age of the data,
  • transparency of data collection processes;
  • scope and scale of the data;
  • relevance (in terms of focus on home consumption);
  • data equivalence and degree of aggregation;
  • objectivity (in terms of degree of impartiality and independence);
  • quality of analysis and recommendations;

This report highlights the most useful sources reviewed, and some of the key issues raised within them, to enable a picture to emerge of the UK’s environmental impacts of household consumption and what more we need to know about it.

2. Key Questions about the Environmental Impacts Of Household Consumption

Evaluating the environmental impacts of household consumption sounds straightforward, but it requires a number of key questions to be answered, particularly about the four key words, environmental, impacts, household and consumption:

  1. What do we mean by “Consumption”? Consumption is usually discussed in economic terms, with an emphasis on expenditure and on purchases of goods and services. From an environmental perspective, it is more useful to consider consumption as a process that encompasses the evaluation, choice, purchase, use and disposal of goods and services.
  1. What do we mean by “Household”? In this report it means: “An individual, family, or group of individuals living together as a unit in a home.” UK households are increasingly diverse, and their consumption activities and resulting environmental impacts will vary to reflect that diversity.
  1. So what constitutes “Household Consumption”.? For the purposes of this report it is defined as “consumption by individuals living in a household, and includes consumption both in and outside the home. For example, food consumed at home and in restaurants”.
  1. What are “Environmental Impacts”: In this report it refers to the impact on the physical or ecological environment. Studies linking household consumption to environmental impacts most commonly focus on release of greenhouse gases (GHGs) and other air pollutants; use of energy, land, water and other resources; generation of waste; and contribution to the acidification and eutrophication of water resources 4.To understand household consumption from a sustainability perspective, it is also important to consider economic and social impacts, and their inter-relationship. However, this report is focused on environmental impacts, which can take place at any point in the product lifecycle or delivery of the service. This includes :
  • Extraction and production;
  • Physical distribution;
  • Resources consumed by marketing and retail activities;
  • The consumers search and purchasing activities (e.g. travel to shops);
  • Product use;
  • Post-use product disposal.

Physical impacts can also have a social dimension. The aesthetic impacts of a housing development, or a wind-farm that supplies it with power, will depend upon individuals’ personal and subjective perspectives and values.

  1. How are environmental impacts measured? Environmental impacts usually relate to the (unsustainable) use of resources; which includes pollution, bio-diversity loss and negative impacts of quality of life including noise, aesthetics and health impacts. Such impacts are measured and expressed in a variety of different ways including :

(a)monetary costs of remediation or loss;

(b)physical quantities of resources used, or waste or pollution produced;

(c)the burden they place on environmental resources.

  1. How can we distinguish between production impacts and consumption impacts? Sustainable consumption and production (SCP) are usually considered in tandem. Various attempts to define sustainable consumption specifically have been made. The UNEP 5 views it as comprising “… a number of key issues, such as meeting needs, enhancing quality of life, improving efficiency, minimising waste, taking a lifecycle perspective and taking into account the equity dimension, for both current and future generations, while continually reducing environmental damage and the risk to human health.” In assessing the impacts of household consumption it is difficult to delineate where it begins and ends. If household consumption is responsible for holiday air miles travelled, is it also partly responsible for aircraft manufacture and airport development and operation ? In seeking to understand the environmental impacts of household consumption, drawing absolute boundaries between consumption and production is unhelpful and virtually impossible. Drawing no distinction is also unhelpful, since the focus becomes total economic activity, not household consumption. This report therefore seeks to emphasise:

(a)Elements of household consumption that have a significant environmental impact;

(b)Elements of consumption where the environmental impacts are most closely linked to behaviour and decision making activities of household members (as opposed to the decisions and activities of producers, or of municipal waste processors).

(c)Those elements of production impacts that the consumer is potentially aware of and may respond to (e.g. organic food production, food miles or use of recycled materials).

  1. Which products and services should we focus on?

The UK is a culturally rich and diverse country, which means that the consumption of its households encompasses a vast range of different goods and services. A review such as this can only hope to focus on certain aspects of household consumption. It is therefore focussed on those elements of consumption that are widely shared, and that have significant environmental impacts. This includes:

  • Dwellings themselves;
  • Food : both eaten in the home and elsewhere;
  • Other household fundamentals : including energy, water, clothes and shoes, and furniture;
  • Household waste;
  • Personal travel;
  • Electronics, computing (including internet use) and domestic appliances;
  • Gardening

3. Influences on the Environmental Impacts of Household Consumption

The most important words for understanding the environmental impacts of any aspect of household consumption are “It depends”, since there are a variety of factors that influence the eventual impacts. Research identifies a range of important influences including: the age profile of the household, its income level, the location of the house (whether in an urban or rural area), access to different forms of transportation, and social background 1. Households are also increasingly fluid. When parents separate they may establish two homes that the children alternate between, duplicating some elements of consumption but spreading others between the households. The UK trend towards a larger number of smaller households has implications for many of the issues tackled in this report. There are one-third fewer people in each household than a generation ago. The average household is now 2.3 people, 0.4 cats and 0.3 dogs 2. In 1961 44% of households were one to two person households, but by 2001 the figure had reached 64% 3.

Partly, the environmental impacts of household consumption depend upon the absolute level of consumption in economic terms. The UK Government’s SCP Framework “Changing Patterns” 6 viewed “Decoupling economic growth and environmental degradation” as an important sustainability strategy. However, this decoupling process will not be easy. Trends in household consumption expenditure against GHG emissions, energy and water consumption, and waste not recycled all suggest that environmental impacts rise as consumers spend more 7. However, the link between the economic and physical dimensions of consumption is not simple. If consumers spend twice as much on food, they are not necessarily buying twice as many items, nor doubling their environmental impact. They could be purchasing more expensive items, including more produce with a lower environmental impact such as organic food. A consumer capitalising on “Buy-one-get-one-free” food offers could also double much of the environmental impact associated with a given level of spending.

When an individual item is purchased and used the ultimate impacts will reflect :

  • the nature of the item (e.g. a large or small-engined car);
  • how it has been produced (e.g. free-range or battery eggs);
  • the distance and mode of travel (e.g. local versus imported foods);
  • how the consumer uses it (e.g. using energy saving settings on appliances);
  • how the consumer disposes of it (e.g. selling on, or throwing away durable items);

Certain types of goods will also have specific influences, so for example the impact of an electrical item will also depend upon whether it uses renewable energy or not.

Therefore there are a number of factors that can moderate the environmental impacts of a given element of household consumption. Consumers can choose products whose production and supply embody reduced environmental impacts (e.g. organic or locally produced food); or choose products that are efficient in use (e.g. energy efficient appliances,) and use and maintain them efficiently to reduce their impact and extend their lifespan; or reduce impacts by finding a second use for old products (through resale or returning it for remanufacture) or by responsible disposal such as recycling or composting.

The key influences on environmental impacts are therefore:

(a)the quantity of consumption;

(b)the environmental quality of production, marketing and distribution;

(c)the efficiency of consumption (in terms of purchase and use);

(d)post-use product disposal.

One final complication is the so-called “Rebound effect”.Thisrefers to consumption increases resulting from the savings associated with efficiency increases 8. If consumers improve their home insulation by 50 %, this will not all translate into reduced environmental impacts. The consumer will use their savings for alternate forms of consumption, perhaps even keeping their home at a warmer temperature.

It is the interaction between the different components of environmental impact (linked to all the stages of the product life cycle) and the various potential moderating factors that makes evaluating the environmental impact of any aspect of household consumption so difficult. Is an organically grown vegetable from another country better or worse than a locally sourced but conventionally grown alternative? Is it better or worse to replace an existing electrical appliance with a new, but more energy efficient, model? These are difficult questions, and precise answers will depend upon the specifics of the products, production processes, product use and disposal. Answers will also vary according to the weights attached to different types of environmental impact. One of the long-running debates is whether disposable nappies are better or worse for the environment than washing and reusing traditional nappies 9. If reducing landfill is emphasised then traditional nappies tend to win this argument, but if energy and water use is emphasised then the disposables can be viewed as preferable.

The better the evidence we assemble about the environmental impacts linked to specific products or specific types of household consumption behaviour, the better we will be able to addresss such questions and develop better products and policies.

4. Environmental Impacts Linked To Dwellings

The home is itself an element of household consumption, as well as the location for much of it. In terms of the environmental impacts of home-buying, there is clearly a difference between buying an existing home and a newly built one. The impacts relating to new homes will relate to the land, energy and the materials used for construction, the waste and emissions generated, and the use of water and discharges to sewer and surface waters. 4,10. For existing homes, when buying, improving or maintaining them, there is also often considerable consumer expenditure on materials, and the volume and nature of these materials will vary according to the size, age and type of dwelling.

Key Information sources on impacts

Entec’s Study of the Environmental Impact of Increasing the Supply of Housing in the UK, (2004) published by Defra 10, considers different housing growth scenarios (from 149-288 K new homes per annum). It focuses on the use of new land and brownfield sites, construction impacts, design issues, occupation issues and also looks at the economic value of environmental impacts, including waste, water, land and CO2 emissions.

For DIY products, both Mintel 11 and KeyNote 12 market data reports show market growth; at 7-8% pa according to Mintel. UK consumer expenditure on DIY tools and materials reached £10.84 Bn in 2004 12. By 2007, the market should be worth £14.8 billion, up 72% on 2001 and 50% on 2002 11. The Mintel report does not mention the potential environmental effects of such growth though the KeyNote report does note that ‘environmental issues concern many of the products sold in DIY shops’.

Key findings

The land-use impacts of planned home building are forecast at between 47 and 78 K hectares of new land between 2001 and 2016. Annual construction impacts using the worst case scenario are forecast at up to 18 million tonnes of aggregates used, 26 million tonnes of CO2 generated and 6.2 million tonnes of waste by 2016 10.

Construction and demolition in England and Wales in 1999 produced over 72 M tonnes of waste (although almost half of this was reused or recycled), and accounted for over 8 M tonnes of oil equivalent in terms of energy 13, but such figures do not separate out housing from non-housing construction.

Various studies investigating the environmental impacts of DIY products for existing homes provide descriptive evidence, but few impacts have been measured and quantified. Some key environmental impacts are outlined below.

Environmental Effects of DIY Products (compiled from various sources14).

Product / Environmental concerns
Paint /
  • Contains harmful chemicals
  • Volatile Organic Compound (VOC) emissions from production and use
  • Waste management issues

Timber /
  • Use of wood from unsustainable sources
  • Deforestation
  • Destruction of biodiversity

Medium Density Fireboard (MDF) /
  • Release of fine dust and formaldehyde fumes

Chemicals e.g. solvents /
  • Pollution risk from spills during production and use
  • Effects on human health

Lighting products /
  • Light pollution
  • Inefficient energy consuming lighting
  • Hazardous materials including lead and mercury
  • Disposal of light bulbs, tubes and fixtures

Packaging /
  • Resource use
  • Waste

Future research needs

Research opportunities in this area include:

  • Understanding the secondary impacts of new housing development (e.g. transport and infrastructure);
  • Developing better tools and techniques to aid comparisons between types and locations of planned housing developments;
  • Establishing consumer knowledge levels relating to the environmental impacts of specific elements of dwelling construction, materials and maintenance;
  • Exploring opportunities for virgin material substitutes such as used glass, shredded plastics and paper sludges;
  • More comparisons of environmental impacts of refurbishing and repairing exsiting housing stock against building new houses to traditional specification and to eco-home specification;
  • More work nationally and regionally on construction and demolition waste as related to specific types of construction project through longitudinal studies.

5. Environmental Impacts Linked To Food Consumption

Food production impacts the environment through agricultural practices which shape our landscape, strongly influence biodiversity, and contribute to water pollution through farm run-off. There is an abundance of data regarding the impacts of food production relating to the use of water, energy and pesticides in particular. The energy consumed in food storage and transportation also has considerable environmental impact and is the subject of increasing research. However, by contrast relatively limited data exists relating to the manufacturing and processing of individual food products and the environmental effects of food distribution and retail.

The consumer’s influence on the environmental impacts associated with food consumption is largely determined by their willingness to buy products with a reduced environmental impact, including:

  • Food produced to organic, or other certified environmental, standards;
  • Local and seasonal produce;
  • Less highly processed and packaged foods;
  • A diet orientated more towards vegetables than meats;

Of course information market failures may mean that consumers’ purchasing decisions do not accurately reflect their willingness to pay for food products with lower environmental impacts.

There are also specific issues in terms of energy used for cooking and food waste. Relatively unusually, food consumption is an area where some consumers can partially fulfil their own needs through growing their own fruits and vegetables.