An empirical study on the effect of factors affecting rehabilitation of aged residential buildings under operation building bright scheme in Hong Kong

Abstract

In recent years, there has been a growing trend of inadequate building maintenance leading to incidents caused by defects in dilapidated buildings, such as concrete spalling. Despite the government's 'Operation Building Bright' Scheme (“OBB 1.0”) launched in 2009 to subsidise flat owners facing financial or technical difficulties in rehabilitating their domestic buildings, the non-compliance rate of the Mandatory Building Inspection Scheme (MBIS) for common areas in buildings, which mandates aged buildings to undergo inspection and necessary repair or rehabilitation works, remains alarmingly high, nearing 90%. With the increasing number of aged buildings in Hong Kong, this concerning lack of maintenance demands immediate attention to ensure public safety. To identify the reason behind the poor state of building maintenance, this study aimed to investigate the determinants influencing the rehabilitation of aged residential buildings in Hong Kong after the implementation of Operation Building Bright Scheme (OBB) in 2009. The results of the study contribute to the formulation of policy recommendations and provide insights into the Operating Building Bright 2.0 Scheme initiated in 2018, as well as any future phase of the OBB Scheme. In contrast to prior research focusing mainly on social and neighbourhood factors, this study specifically examines financial, building-related, and development factors using logistic regression tests. A total of 117 aged residential buildings in the Kowloon City District, which had either already undergone rehabilitation or were not rehabilitated yet, were analysed. Through literature review, 9 key factors were identified and subsequently categorised into three main dimensions, including economic considerations, building characteristics, and development control parameters. These factors include average rehabilitation cost paid by each flat, tender price index, external physical condition, presence of lifts, age of rehabilitation, number of flats, presence of Owners' Corporation, number of floors and class of site. Statistically significant factors include “external physical condition,” "presence of lifts," “average rehabilitation cost paid by each flat,” "class of site," and "number of flats." The results of the logistic regression test indicate a positive correlation for the factor "presence of lifts," suggesting that buildings with lifts are more likely to undergo rehabilitation. Similarly, both Class A and Class B sites show positive correlations, indicating a higher likelihood of rehabilitation compared to Class C sites. Besides, the number of flats also exhibits a positive correlation, meaning that buildings with a greater number of flats are more likely to undergo rehabilitation. The results show that the predicted probability of aged buildings undergoing rehabilitation is nearly 0% when they are situated on a Class C site, regardless of whether there is a lift in the building. For aged buildings with fewer than 40 flats, those with lifts are predicted to have at least an 80% higher probability of undergoing rehabilitation compared to those without lifts, 5regardless of whether they are situated on Class A or B sites. However, when the number of flats exceeds 70, the predicted probability of undergoing rehabilitation exceeds 95%, irrespective of whether there is a lift present. The empirical findings underscore several significant implications. Firstly, flat owners of buildings on Class C sites appear to be the least likely to undergo rehabilitation compared to those on Class A and B sites, largely due to the higher redevelopment potential associated with Class C sites. Owners may be less motivated to invest in maintaining the condition of the building, given the likelihood of it being acquired for redevelopment. Secondly, owners of buildings without lifts exhibit lower willingness to undergo rehabilitation, likely influenced by the reduced livability associated with such buildings. Accessibility issues, inconvenience, and potential decreases in property value contribute to this reluctance to invest in rehabilitation efforts, as owners may perceive these buildings as less desirable for tenants or residents. Thirdly, flat owners are more likely to undergo rehabilitation when buildings have a greater number of flats, as larger-scale buildings typically have more comprehensive building management practices in place.