Tampines residents complain of ceiling leaks, mould; HDB says solar panel installation not the cause

SINGAPORE: When a downpour persisted for days during the rainy season last December, Mr David Mohan was dismayed to find water dripping from his kitchen ceiling for days on end.

Pails placed below the leak would be filled within “three to four hours”, which meant that Mr Mohan and his wife had to take turns waking up during the night to empty the pails.

“It was like raining in my house,” said the 66-year-old retiree, who lives on the top floor of one of the Housing and Development Board (HDB) blocks along Tampines Street 21. 

At that time, solar panels were being installed on the block's rooftop.

“Before the (installation) works, there were no leaks. We don’t know what happened,” Mr Mohan told CNA at his home last month.

He turned to the town council and later HDB for help. While his leaking ceiling was patched in January, Mr Mohan remains worried about whether the leak had caused any damage to the false ceiling in his kitchen, as well as a built-in cabinet located near the leak. 

Mr Mohan intends to get a contractor to conduct a thorough check when the installation of solar panels at his block is completed. 

At least three other residents who live on the top floors of several blocks in the area told CNA that they experienced leaks, mould growth and water patches on their ceilings as the installation of solar panels was carried out.

In response to CNA’s queries, HDB said on Monday (Oct 7) that inspections by the solar panel installation contractor for HDB blocks in Tampines Street 21 had identified ceiling cracks and leaks, among other issues, before installation commenced.

These were being fixed on a "goodwill" basis by the contractor, sometimes in tandem with the installation works. 

HDB also said that contractors commissioned for all its solar panel installation projects “are not allowed to drill or puncture” the rooftops of HDB blocks.

“Instead, it is mandatory for the solar panels to be weighed down by concrete ballasts placed on felt pads,” its spokesperson added.

These felt sheets serve as a “protective membrane” for the roof and create an additional layer “aimed at preventing water leakage into the rooftop surface underneath”.

“Therefore, any subsequent ceiling leakage is unlikely the result of solar panel installation and more likely due to the natural deterioration of the roof’s existing waterproofing membrane or coating,” HDB said.

The HDB blocks at Tampines Street 21 were built between 1982 and 1987, with the majority built in 1984.

“PATCHES” ON CEILING, MOULD IN WARDROBES

The installation works at Tampines Street 21 are part of the government’s SolarNova programme, which has seen solar panels being fitted on the rooftops of thousands of HDB blocks throughout Singapore to harness clean energy and make housing estates more sustainable.

Under the programme, solar energy is used to power common services in HDB estates, such as lifts, lights and water pumps, during the day.

On average, this enables the HDB blocks to achieve net-zero energy consumption for the common areas, and can help town councils to moderate increases in operating and maintenance costs, authorities have said.

When CNA visited the Tampines HDB estate last month, installation work appeared to be ongoing at six HDB blocks. The noise of drilling could be heard intermittently at Block 256 throughout the day. 

According to a resident of Block 256, the solar panel installations began in late November last year and lasted until March before restarting recently on Jul 31. The installation work is set to go on until the end of this month, based on the paper notices pasted at the lift lobbies of blocks 255 and 256.

One resident of a top-floor unit of block 256, who asked to be anonymous as he is a tenant, has observed “patches” appearing on his kitchen ceiling in recent months. The washing machine and one of the ceiling lights in the kitchen also “stopped working” on separate occasions and had to be replaced. 

The resident said he had asked the construction workers at his block to take a look at his flat, but was told they were “unable to identify the cause” of the ceiling “patches” and the electrical issues.

Another top-floor resident in the same block said members of the household started noticing mould in two of their bedroom wardrobes in August.

“With more drilling done on the rooftop, the mould got worse, especially for the wardrobe in the master bedroom. Minor water leakage at the ceiling also started,” said the resident who wished to be known only as Emily. “This has never happened before.” 

The family has since placed more disposable dehumidifiers in their wardrobes and runs an electrical dehumidifier around the house more often. While the mould and ceiling leaks have stopped, the family has contacted the town council for assistance.

NO TREND SHOWING THAT SOLAR PANEL INSTALLATION CAUSES CEILING LEAKS: HDB

In its response, HDB said the contractor carrying out the solar panel installations at Tampines Street 21 has done so according to established work processes. 

These include the laying of the protective membrane beneath the concrete ballast that supports the solar panels and their frames.

Also, no drilling is done directly on the surface of the reinforced concrete roof to maintain the roof’s existing waterproofing membrane.

The contractor for the project is Novasix, which has engaged Alpina Energy for the installation, testing and commissioning of the solar photovoltaic systems.

Novasix is a joint venture formed by Digo Corporation, a wholly owned subsidiary of Alpina Holdings, and Terrenus Energy after the two firms were jointly awarded the sixth solar leasing tender under the SolarNova programme in March 2022.

Alpina Energy is a wholly owned subsidiary of Alpina Holdings.

As part of the work processes, HDB said Novasix also conducted “pre-condition surveys” before work commenced. 

During these physical inspections, the contractor found that some residential units “faced existing issues of ceiling cracks, wet patches, and water leakage”. These could have been caused by a variety of factors, such as heat expansion or contraction, as well as natural wear and tear over time.
 
HDB said: “To facilitate the SolarNova installation at Tampines Street 21 and expedite the rectification of some of these roof issues typically done by town council, Novasix has been working closely with the affected residents to rectify these issues on a goodwill basis.

“Most of the repair works have already been carried out, and some of them were done in tandem with the installation works for the solar panels.” 

HDB also said that Novasix is “working closely with Tampines Town Council and residents to resolve any existing issues before beginning installation at the remaining 475 blocks in the town”.

In its reply, HDB did not indicate how many residents are affected. A separate query to the Tampines Town Council on how many residents have reported issues of ceiling leaks or cracks was not answered.

Alpina Energy declined to respond, noting that it "has nothing more to add" to HDB's statement. CNA has also contacted Terrenus Energy for comment.

Overall, HDB stressed that it has received “an average of fewer than 30 cases of feedback a year on ceiling leaks for top-floor units” since works under the SolarNova programme started in 2018.

“This is out of approximately 4,200 HDB blocks installed with solar panels to date, which works out to less than 1 per cent of the installed HDB blocks being affected by ceiling leaks,” it said.

“There is no trend indicating that solar panel installation leads to an increase in the number of ceiling leaks at the top-floor units.”

LACK OF REQUIRED MATERIALS CAUSING DELAYS: HDB

Residents at Tampines Street 21 also sounded concerns about the noise and slight inconveniences caused by what seems to be a prolonged installation work that has been going on since the end of last year.

In its reply, HDB noted that the solar panels at Tampines Street 21 are being installed progressively. 

It added that the time taken from panel installation to system activation “typically ranges from four to six months per block”. However, there were nine blocks “that took longer than anticipated as one of the sub-contractors faced issues securing the required materials for installation works”.

“With the issue resolved, the installation works which were earlier paused are now expected to complete by end of this year,” HDB told CNA.