Debated in Parliament on 4 Aug 2026.
Ms Lee Hui Ying asked the Minister for National Development (a) whether HDB has carried out any internal study on the effects of rooftop solar panels on top-floor HDB units; (b) how many ceiling leakage complaints were received annually in the past two years for top-floor units (i) with and (ii) without rooftop solar panels, respectively; and (c) whether there is a higher incidence of ceiling leaks for flats with rooftop solar panels.
Solar panels are installed on the Housing and Development Board (HDB) rooftops via a non-invasive installation process, without any drilling into the roof or waterproofing membrane. The panels are secured using concrete ballasts placed on protective felt pads, which cushion the roof surface. For each installation, a professional engineer ensures that the ballasts are correctly installed and do not affect the waterproofing membrane.
HDB conducted a comprehensive study in 2025 on the effects of solar panel installation on the rooftops of HDB blocks. The study covered 8,800 ceiling leak cases reported at top-floor units across the entire stock of more than 10,000 HDB blocks over a 10-year period and found that solar panel installation did not result in top-floor ceiling leaks. The occurrence of top-floor ceiling leaks remained consistent before and after solar panel installation. There was also no difference in the incidence of top-floor ceiling leak issues between blocks with and without solar panels.
Data from the last two years is consistent with findings from the 2025 study. Of the 1,200 top-floor ceiling leak cases, the incidence of such cases for blocks with and without solar panels is similar.
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