Hong Kong's housing shortage and sky-high property prices have forced many grassroots families to live in cramped, poorly equipped subdivided units. To examine the impact of these living conditions on children's development, the Public and Social Policy Research Centre of the School of Arts and Social Sciences at Hong Kong Metropolitan University (HKMU) partnered with the Society for Community Organization (SoCO) to conduct a longitudinal study. The findings from the first phase reveal that the narrow, overcrowded and noisy environment of subdivided units significantly affects children's mental well-being, academic performance and daily life. The survey found that nearly 40% of children living in subdivided units feel they lack adequate space for studying, and over 40% feel they lack space for play. These children also display significantly higher levels of depression, anxiety, and stress.

The three-year mixed-methods study examined how Hong Kong's subdivided housing affects child development. In the first phase, from June 2023 to August 2024, researchers conducted surveys with 1,032 Primary 4 to Primary 6 students (from both subdivided and non-subdivided units), cognitive-behavioural experiments with 160 children (80 from subdivided units and 80 from non-subdivided units), and in-depth interviews with 54 children.

The survey found that 39.1% of children living in subdivided units felt they lack suitable space for studying at home, and 43.9% felt they lacked space to play—figures significantly higher than those of their peers in non-subdivided units. In addition, 19% reported serious noise problems at home, and 42% described severe overcrowding. Interviews revealed that many children had to study or engage in other activities on their beds or dining tables and often had to move or discard study materials due to lack of space. Their opportunities for recreational activities were also extremely limited.

In terms of mental health and emotional well-being, children who felt they lacked adequate space to play exhibited higher levels of depression, anxiety and stress—16%, 9% and 10% higher, respectively—than those who felt they had adequate space. They also experienced 40% more emotional issues and 10% more behavioural problems. Similarly, children who reported a lack of study space had depression, anxiety and stress scores 11%, 4.5% and 4.6% higher, respectively, than those of their peers, and their overall life satisfaction was 15% lower.

These findings indicate that cramped living conditions negatively impact children's emotional stability and behavioural functioning, possibly impairing their ability to regulate emotions and cope with stress. Many children reported feelings of helplessness, anxiety and irritability due to prolonged confinement in small spaces. Some also reported strained parent-child relationships and family conflicts.

Regarding academic performance, only 53.7% and 54.6% of children who felt they lacked study space scored A or B in Chinese and Mathematics, respectively—significantly lower than the 64.6% of those with sufficient space. Cognitive experiments revealed that perceived spatial constraints negatively affected children's language memory and attention. Interestingly, however, children lacking study space performed better in self-control tests, suggesting they may have developed stronger self-regulation skills in response to their challenging environments.

The study found that households in subdivided units had significantly lower median incomes. As a result, many children lacked stable internet access and computer equipment, hindering their participation in online learning. Most spent their after-school hours playing electronic games or watching online videos, with limited opportunity for outdoor or diverse extracurricular activities. Parental support for learning was limited, and digital literacy development was lacking. While parents imposed many rules on device usage, they often failed to provide constructive guidance, leading to parent-child conflicts.

Prof. Charles Kwong Che-Leung, HKMU Vice President (Administration and Corporate Development) and Director of the Public and Social Policy Research Centre, noted that subdivided units have long been a public concern. According to the 2021 Population Census, about 34,000 children live in such housing. “As an academic institution, we hope our findings can draw society's attention to the challenges faced by children in subdivided units and provide an objective and comprehensive analysis, along with recommendations to help the government formulate more targeted family and child policies,” he said.

Dr Terence Shum Chun-tat, Acting Head of the Social Sciences Department and Deputy Director of the Public and Social Policy Research Centre at HKMU, who led the study, said, “This research confirms that children living in subdivided units face multiple challenges in physical and mental health, academic performance and life experiences. Overcrowded housing is not merely a housing issue; it is an urgent concern for child development.”

Ms Sze Lai-shan, Deputy Director of SoCO, added, “For years, we've witnessed children struggling to grow up in cramped conditions. This study vividly illustrates their harsh realities and clearly shows how the lack of space contributes to learning difficulties and psychological stress.” She suggests that the Government increase learning spaces for these children, both within the community and on school campuses, to address their pressing needs.

The research team recommends that the government conduct in-depth studies on various vulnerable groups living in subdivided units (such as underprivileged children and new immigrants) to develop more precise poverty alleviation policies. They also suggest a closer examination of the developmental needs of children in subdivided units, with appropriate service support. They recommend consolidating the current “Subsidy Scheme for Internet Access Charges” and the “e-Learning Funding Programme” into a unified “e-Learning Support Scheme” to directly fund the purchase of computers and internet access for underprivileged students. Additionally, the government should implement fee waivers or reductions for youth centres and public recreational programmes for children from low-income families, including those living in subdivided units, to allow them to participate more fully in extracurricular and leisure activities.

Dr Shum noted that the research team had already launched the second phase of the study, which continues to track the same group of children to examine how transitions—such as moving into secondary school or changes in living conditions—affect their mental health, academic performance and long-term development. The team will formulate more comprehensive and targeted policy recommendations based on these findings.