Windows Are the One Job Your Renovation Contractor Cannot Do

There is one line that appears on renovation quotations more often than it should: "replace windows", sitting between the hacking and the carpentry as though it were the same kind of work. It is not. Window replacement in an HDB flat is the one common renovation item that your renovation contractor is not allowed to carry out, no matter how good he is or how long he has been registered.

This is not a technicality and it is not us passing work to somebody else. It is a separate licensing regime, with its own register, its own trained installers and its own permit. Here is how it actually works, what it means for your renovation sequence, and why a quotation that quietly includes windows tells you something about the rest of the quotation.

Two different licences, and they do not overlap

Being an HDB Registered Renovation Contractor lets a firm carry out renovation works in HDB flats and apply for renovation permits. Larry Contractors holds that registration — HB-09-5667H, printed in the footer of every page on this site, and you can verify it yourself the way we describe in our guide to checking an HDB registered renovation contractor.

Window installation and replacement is governed separately. The work must be carried out by an approved window contractor — a firm registered with the Building and Construction Authority under the workhead for windows (RW01), or a licensed builder employing Trained Window Installers. HDB publishes the directory of approved window contractors, so the list is public and checkable.

A renovation registration does not grant window approval, and window approval does not grant renovation registration. They are two lists. A firm can be on both, and many window specialists are on neither renovation list because windows are all they do.

Why the rule exists

Because windows fall. Singapore has had enough fatal and near-fatal incidents from windows detaching from high-rise flats that the whole area was pulled into its own regulatory lane, and the failures were usually not dramatic — they were fasteners.

The clearest example is the retrofitting order BCA issued in 2004 on aluminium casement windows: the original aluminium rivets holding the window panels to their frames were found to corrode, and owners were required to have them replaced with stainless steel rivets. A corroded rivet gives no warning. It looks identical to a sound one until the panel is on the ground.

That is also why BCA and HDB tell flat owners to inspect their own windows regularly rather than waiting for a problem: look at the rivets and hinges for rust staining, check that the panel does not rattle in its frame, and try the mechanism. It takes two minutes per window and it is the only inspection most windows will ever get.

Three things people get wrong

1. "It is only a repair, so it does not count." Replacing rivets, hinges or a whole panel is still window work. The safest way to think about it is that anything that unfastens the window from its frame belongs to the approved contractor.

2. Full-height windows. Replacement of full-height windows in HDB flats is not permitted. If your flat has them, the conversation is about maintenance and repair, not swapping them for something else.

3. Windows with a safety barrier built in. Three-quarter-height and full-height windows often have the safety barrier integrated into the window itself. Replacing or reinstating one of those is a narrower job again: it has to be done by a licensed builder or an approved window contractor whose installers have completed BCA's specific module on replacing and reinstating safety barriers integrated with windows. If your windows have a railing that is part of the frame rather than bolted to the wall in front of it, say so when you ask for quotations — it changes who can quote.

What this means for your renovation sequence

The practical consequence is that you are running two contractors on one flat, and the order matters.

Windows generally go early, and here is why. Replacing a window is dusty, involves cutting out the old frame, and usually needs making good around the reveal. Doing it after the walls are painted, the flooring is laid and the curtains are up means paying twice for finishes that were already right. If windows are in the plan, they belong near the start, with the wet works — the same logic we set out in the week-by-week renovation timeline.

Grilles are a separate decision again. If you are adding or replacing window grilles, sort that out with the window works rather than after, so the fixing points and the window operation are considered together. A grille fitted without thought about how the panel swings is a window you can no longer clean.

The two permits are not one permit. Window works need their own HDB permit, applied for by the approved window contractor under their own registration. Your renovation permit does not cover them and cannot be extended to. If you assumed one permit covered everything, this is the point at which the schedule slips. Our guide to HDB renovation permits covers what your renovation permit does and does not include.

The quotation test

Here is a way to use this that is worth more than the rule itself.

If a renovation quotation includes window replacement in the general scope, with no separate window contractor named, ask one question: "which approved window contractor is doing the windows, and can I have their name?"

A straight answer means the firm has a window specialist it works with and simply did not break it out — fine, ask for it in writing. No answer, or a vague one, means either the work was going to be done by someone not permitted to do it, or nobody has thought about it yet and the number in front of you is a guess. Both are worth knowing before you sign, and both say something about the rest of the pricing. This is the same reasoning we apply to the other licensed trades on a renovation: electrical work needs a licensed electrical worker and plumbing needs a licensed plumber. Windows are the third one, and the one most often forgotten.

What we do about it

We say it early. If windows come up at the quotation stage, we tell you it is not ours to do, tell you where the approved list is, and plan the programme around when the window contractor can come — because the sequencing is genuinely our problem even though the work is not. Then we make good around the new frames as part of the renovation.

Working as a direct contractor makes that easier rather than harder: there is no layer between you and the person building the schedule, so a window date that moves gets absorbed by the programme instead of quietly costing you a week. What we are licensed to carry out ourselves is set out on our HDB renovation page.

The short version

• HDB window installation and replacement must be done by a BCA-approved window contractor, or a licensed builder with trained window installers. A renovation registration is a different list.
• Repairs that unfasten the window count as window work. Full-height window replacement is not permitted.
• Windows with an integrated safety barrier need installers who have completed BCA's specific module for that work.
• Window works carry their own HDB permit. Your renovation permit does not cover them.
• Schedule windows early, with the dusty works, not after the finishes.
• If a renovation quotation includes windows without naming the window contractor, ask for the name. The answer tells you a lot.

Planning a renovation and not sure where the windows fit? WhatsApp us on 9107 2601 — tell us the flat type, roughly how old it is and which windows you are thinking about, and we will tell you what belongs to us, what has to go to an approved window contractor, and the order that keeps you from paying for the same finish twice.