What can be done about damp and mould?

The potential severe consequences of exposure to mould in damp housing were brought into sharp focus by the tragic death, in December 2020, of two-year-old Awaab Ishak who died from a respiratory condition caused by prolonged exposure to mould in his parent's home in Rochdale, Greater Manchester.

At the end of the inquest into Awaab's death, the senior coroner, Joanne Kearsley said: “I’m sure I’m not alone in having thought, ‘How does this happen? How, in the UK in 2020, does a two-year-old child die from exposure to mould in his home?’. The tragic death of Awaab will and should be a defining moment for the housing sector in terms of increasing knowledge, increasing awareness and a deepening of understanding surrounding the issue of damp and mould.”

In response to the incident, which gained nationwide coverage, Michael Gove (Secretary of State for Levelling Up, Housing and Communities) and Steve Barclay (Secretary of State for Health and Social Care) set out five areas of concern and said they wanted to update current guidance on social housing, including guidance on damp and mould, as well as changes to the housing health and safety rating system. The Ministers also commented that important health information about damp and mould cannot be easily accessed.

The housing provider, Rochdale Boroughwide Housing (RBH), accepted at the inquest that a more proactive approach should have been taken to tackle the mould after Awaab's parents accused RBH of doing nothing over a number of years to tackle the mould problem. Local Authorities have since issued reminders to renters about their rights when dealing with mould and how to seek help if their landlords are not taking appropriate action. Ministers have announced that landlord guidance on the health risks of damp and mould is to be reviewed following the tragic death of a young child in Rochdale.

So how does damp and mould affect health, and what can a householder do to prevent or reduce it and hence avoid such severe consequences as seen in Awaab Ishak’s case?

In 2009, the World Health Organisation (WHO) published a guidance document: ‘WHO Guidelines for Indoor Air Quality: Dampness and Mould’ accompanied by an information brochure ‘Damp and Mould: Health risks, prevention and remedial actions’ intended to raise awareness amongst the general public. The WHO report concluded that sufficient evidence was available from studies conducted in different countries and different climatic conditions to show that occupants of damp or mouldy buildings are at increased risk of respiratory symptoms, respiratory infections and exacerbation of asthma. Moreover, results of intervention studies showed that remediation of dampness can reduce adverse health outcomes. In addition, WHO found clinical evidence that exposure to mould and other damp-related microbes increases the risks of rare conditions such as hypersensitivity pneumonitis, allergic alveolitis and allergic fungal sinusitis. Importantly, although atopic and allergic people are particularly susceptible to damp indoor environments, adverse health effects have also been found in the general population. Dampness and mould tend to be particularly prevalent in poorly maintained housing for low-income people – a population group that is already disadvantaged.

Mould growth is dependent on water being present in or on materials within the dwelling. Microbes propagate rapidly wherever water is available, with the dust and dirt present in most dwellings providing sufficient nutrients for growth.

While the adverse health impacts of damp and mould have been known for decades, the specific causative agents have not been conclusively identified, and no quantitative health-based guideline values exist for microorganism contamination. It is therefore necessary to take holistic action to prevent and/or remediate damp and mould problems. This may explain why relatively little has been done about the problem, especially in social housing.

Since damp and mould in buildings is due to a combination of high humidity and cold surfaces, caused by poor insulation, an effective strategy has to address both these conditions. The former may require behavioural changes that are difficult to achieve, whilst the latter often necessitates expensive building renovation work.

However, since control of mould and damp is best achieved by preventing excess moisture within the dwelling, controlling the humidity of the indoor air and preventing or limiting condensation can be an important and effective mitigation strategy. Occupant activities and behaviours are significant contributors to increased indoor moisture levels, and these provide a handle for potential effective remedial actions.

Application of IAQ monitors that allow humidity levels to be monitored can at least inform the building occupants when humidity is high; the IOT Air365 device provides both alerts and information on what action can be taken to reduce humidity levels. In this way acute episodes of high humidity can be identified and action taken to mitigate them. In addition, conditions of persistently high humidity, that over time will inevitably lead to damp and mould problems and possible adverse health impacts, can be monitored, allowing mitigation strategies to be implemented and their effectiveness monitored.

Intelligent IAQ monitors can thus allow issues of damp and mould related to high humidity to be detected early, and suggest appropriate action to address the problem. This is particularly important for social housing, as persistent damp and mould can lead to building damage which will cost more to repair if prompt action is not taken. Prevention and remediation of damp and mouldy conditions in poorly maintained housing for low-income individuals must be a priority in order to prevent an additional contribution to poor health in populations that are already living with an increased burden of disease – and avoid tragedies such a that suffered by young Awaab.

Prof. Paul Harrison, Sensyqo

8th February 2023