Most of us don’t think too much about the windows in our HDB flats… until it becomes a problem.

Then we might find out it’s a pricey nightmare to change them; or that the type of windows we have can make a huge difference at resale.

This week, we followed a homeowner, M, and her problems with her HDB windows.

At the same time, we thought we’d take the opportunity to highlight some interesting pointers about flat windows before you purchase any HDB flat.

How M’s windows became the biggest renovation issue

M purchased an older resale flat, for the benefits of the size and the well-built up neighbourhood. As with most resale flats, there tends to be more renovation work required. 

This in itself wasn’t a problem; what’s surprising is that for M, the windows became the “highlight of my whole reno nightmare”. In fact, it took 10 months before M could move in, and it was largely due to the windows.

M had a bit of early warning about this:

“I had an interior designer. I chased about the status of the windows since the rest of the house was done, and we were just waiting for new windows. The designer said it’s a long process and that it might even take six months or a year. 

I found that ridiculous and suggested that we part ways, without her charging me for the windows; anyway, no work on the windows had been done. She agreed readily and almost seemed relieved. Looking back, I now understand why.”

We’re a little surprised that the interior designer didn’t foresee the problem with the windows earlier; most of the time, designers and contractors are quick to identify these issues.

Nonetheless, this shows that it can be worth asking about the windows and required approvals early on – sometimes it can nudge the contractor into finding out things even they didn’t expect. 

It was all about the height of the window from the ground

M says that: “According to HDB, my floor to window height was below the permitted one metre. This meant I needed a Professional Engineers (PE) endorsement, if I wished to change the windows.

"For your info, many, many BTOs today feature nice big windows which are also low, and this will definitely become a major issue in 10 to 20 years when homeowners want to change their windows.”

A PE endorsement is required to make major structural changes to your house; it can be pricey, as we’ll explain below, and it may not be cost-effective when it’s just for one purpose like changing a window. 

There are two other interesting things to note here. 

First, there are indeed more flats with larger windows these days. A good example of this would be SkyTerrace @ Dawson, which recently broke the million-dollar mark (you can clearly see the window sizes in the linked article).

Some other HDB developments with these windows include Waterway View, and Woodleigh Glen.

These windows are indicated on the floor plans HDB provides; just look for windows labelled W1 or W2 – this refers to windows that are larger than normal (usually these windows are only in the living room, but some developments have them in other rooms as well, like the master bedroom). 

Second, keep this in mind when changing your floor height. If you have some kind of flooring material that raises the floor height, it can actually lower the distance between the floor to window.

If this distance is less than one metre, you may also end up needing special approval and inspections (if it’s not disallowed outright). 

M says: “I agree that my windows are rather low at around 75cm, but the window height is original and I did not make any changes… I discussed this with HDB several times, and they visited me to measure the windows but stood by their decision. 

“I had to install a bottom fixed panel for all my windows so that they meet the one-metre requirement. Windows with bottom fixed panels would of course cost a bit more. But given the safety issues, I was willing to adhere to HDB’s requirements and pay for more expensive windows, as well as an additional few thousand dollars for PE endorsement.”

Unfortunately, getting PE endorsement for just the windows was a major hassle 

M says that “searching for a PE was not difficult, although the cost range was wide, from $3,000 to as much as $12,000.”

This is because engineering can range from large establishments that handle entire buildings, to those who work with smaller contractors. It may not be well-differentiated on their websites, so you need to do a lot of manual searching. 

M was also told that she needed a contractor with a General Builder (GB) license. This probably refers to the GB License Class 2 (you can see the different classifications on the BCA website). And herein lies a problem:

“I called them one by one, and almost all but a few told me they do not install HDB windows, they are builders who build entire buildings. How did the rest of the homeowners change their windows, I wonder?”

Our answer is that they generally don’t – most people don’t ever change their HDB windows, so they rarely encounter this issue. M was simply unfortunate, in that “My windows are old and whenever it rains, it leaks badly so I have no choice but to change them.”

M was also advised not to change her windows at all:

“I even had a few window contractors who advised me not to change my windows. They said I’m paying a few thousand dollars just to get a ‘chop’ (stamp of approval) from a PE, it’s not worth the money. 

“No one thinks highly of the requirement for PE endorsement. To me as a homeowner, I assume PE endorsement is for a professional engineer to verify and sign off for major building works; and it’s clearly difficult work that requires a few thousand dollars, equivalent of someone’s monthly salary.

"However, most contractors tell me that PEs just sign on a piece of paper. It’s not worth the money to engage them. If possible, I should not change my windows to save the money and the trouble.”

We asked around a bit though, and it’s not so much that the PE endorsement isn’t respected – rather, the response we got was that getting PE endorsement for just this one thing (changing the windows) would not have been cost-effective. 

Most of the time, when PE endorsement is needed, it’s for a range of major structural issues, or large-scale projects (e.g., a developer needing PE endorsement for multiple reasons in a whole condo project).

To use an analogy, getting PE endorsement for small changes is like paying a private specialist to check out your mild cough. You could, but it’s burning a hole in your pocket. 

For M, the cost to her was exorbitant – but even then, many of the firms wouldn’t accept the work (it may have been on too small a scale for them).

M estimated that it would have cost a total sum of $10,000 for the new windows and for the PE endorsement; but many contractors and engineering firms still turned down the work even when she was willing to pay. 

Some contractors also told M about an unofficial industry practice:

“People don’t talk openly about it, but apparently, I was told contractors ‘borrow’ another General Builder’s license so they can proceed with the paperwork.

"Most window contractors don’t have the GB license, but have the skills to change the windows; so they just use someone else’s license for the paperwork.”

This sort of arrangement does happen, but we’d caution against it. If something goes wrong (e.g., the under-the-table contractor does serious damage), you might end up saddled with no compensation. 

Note that most home insurance does not cover damages caused by your contractor; the contractor is supposed to claim it from their own business insurance. Some contractors may be reluctant to do this, since it raises questions they’ll struggle to answer. 

Doing it fast may have cost over $20,000

“I even wrote to my MP to seek help at one point,” M says, “but I didn’t even receive an acknowledgment reply. I was really frustrated with the process, how long it has taken and the complex, uncooperative, and dishonest culture of the renovation/construction industry.”

“If I had more money, perhaps paying $12,000 for PE fees and $10,000 for the windows, I could get the windows changed in a much shorter time frame; but I didn’t buy a HDB to spend over $20,000 just to change my windows.”

“I would say the one positive outcome from this nightmare was that I had a great engineering firm who really helped me through the process, and helped to chase the contractor for the necessary paperwork, etc.”

M did finally get her windows changed with the help of the engineering firm.

However, doing it the slow way was what caused her to wait 10 months for the renovation to be complete, and it was only after a lot of manual legwork to find the right people. 

So if you’re buying a flat, beware of windows that need replacing (or which may need replacing in the future) 

Bigger windows can provide a more dramatic view – but remember you may run into similar problems as M.

If you’re in doubt, get an expert to look over the windows before you buy. Don’t assume the windows are always a minor fix. 

A quick side note on larger windows 

Do keep in mind that larger windows also allow in more heat, so the facing of your unit really matters if you have huge living-room windows. Otherwise, you may need pricier thermal curtains. 

Also, the placement of W1 and W2 windows (check the floor plan) can affect the way you position your furniture – you usually want to keep the entire space in front of the large windows clear.

It can be a bit awkward to push a sofa, bed, or desk up against a near floor-to-ceiling window. 

During the day, light reflection off a TV or computer screen can also be blinding, unless you angle them away from large windows (directly across from the window is the worst, so don’t put the TV or desk there).