The 2019 Climate Change Act committed the UK to reducing its emissions of greenhouse gases to net zero by 2050. The 2019 UK Clean Air Strategy, sees "air pollution as one of the UK's biggest public health challenges", aims to secure clean growth whilst tackling air pollution through reducing emissions. Achieving these reductions in greenhouse gas and air pollutant emissions will entail substantial reductions in use of fossil fuels and changes to the transport fleet over coming years as we make the transition to a 'low carbon economy'. This will also have an important benefit for health of improving levels of outdoor air pollution by reducing emissions from power plants, motor vehicles, wood/coal burning at home and other sources. However, another important climate change action is to improve energy efficiency in homes. Those measures typically entail reducing levels of ventilation to cut down heat losses from escape of heated air. In addition to helping improve winter indoor temperatures, this can be beneficial for human health because it reduces the penetration into the home of air pollutants from the outdoor environment. But it will increase indoor levels of air pollutants derived from sources inside the home - such as particles and gases generated by cooking, volatile organic compounds (VOCs) given off from fabrics and furnishings, cleaning and personal care products. The changes to indoor pollution levels from improved home energy efficiency may thus be overall positive or negative for the health of building occupants depending on the balance of effects on pollutants entering and leaving the indoor environment. That balance is likely to depend on the levels of outdoor pollutants, indoor air pollutant sources and activities that generate these, the form of the energy efficiency improvements, the behaviour of occupants and their vulnerability to air pollutants. People at particular risk are young children, the elderly, those with pre-existing illnesses, and those experiencing social deprivation. To improve understanding of these issues, we have created a new research network (acronym 'HEICCAAM'). This network brings together experienced and early career researchers from nine universities from disciplines as diverse as air quality measurement and modelling, building physics, behavioural science, health and health inequalities, education and policy. The network will also include representatives of the public, as well as stakeholders from the public sector, business/industry and non-government bodies - including Public Health England, Health Protection and NHS Scotland, Scottish Environment Protection Agency, Age UK, the Passivhaus Trust, Good Homes Alliance, Edinburgh City Council, the Chartered Institution of Building Services Engineers and the UK Met Office. The network will build evidence on the consequences for exposure to air pollution of actions aimed at tackling climate change and poor air quality, with particular focus on the home environment. Its aim is to provide underpinning research that can inform and influence policy and practice to safeguard human health. The network will include activities by six Working Groups tasked with generating a series of papers on relevant issues of science and policy. It will also undertake four small research projects aimed at improving understanding of key issues where there are knowledge gaps. It will have a particular focus on protecting the health of vulnerable groups and reduction of health inequities. Network members will have multiple interactions through electronic meetings, webinars, discussion groups and an annual meeting and workshop with a wider group of stakeholders. Through its activities, the network will help build long-term capability in interdisciplinary research in this area, including through the interactions with early career researchers, the development of new research plans, and linkage to other networks and existing research programmes.