Maintenance performance evaluation of offsite and in situ bathrooms

Purpose – Offsite is one of the main innovative techniques employed in the contemporary UK construction sector. Building maintenance accounts for over 5 percent of the UK's gross domestic product of which bathrooms are regarded as a critical area, with potential high risks and defects. However, the importance of its maintenance has been largely underestimated and research into this area appears to be limited. This paper aims to address this knowledge gap by investigating the maintenance performance of offsite and in situ bathrooms for student accommodation. Design/methodology/approach – The paper examines 732 maintenance records over three years of 216 precast concrete modules, 84 Glass Reinforced Polyester (GRP) modules and 96 traditionally-built in situ bathrooms. Findings – The research found that offsite modules outperformed in situ bathrooms in terms of maintenance. GRP modules created the least maintenance problems, compared to precast modules and in situ bathrooms. The maintenance of in situ bathrooms was more complex than offsite modules, and involved more diverse problematic areas. The main causes of the problems included inappropriate design; poor build workmanship, lack of quality of component materials and improper usage by occupants. This supports a parallel study that found that the costs associated with maintenance were significantly higher for in situ bathrooms than for the equivalent offsite solutions. Research limitations/implications – The paper contributes to understanding the problems of offsite bathroom modules requiring maintenance in comparison with in situ bathrooms and their possible causes. Key aspects of offsite bathrooms including drainage, toilets, vents and sinks should be improved. Quality of component materials used for in situ bathrooms should be ensured. These improvements can only be achieved through better design for maintenance with clients' aspiration embodied. The findings should assist in design decision making of selecting bathrooms for residential buildings. However, a balanced approach, taking into account other factors for such selection, is open for future investigation. Originality/value – The framework of strategies developed should improve the innovative design of bathrooms manufactured offsite and help maintain them for better lifecycle performance.