Replacing an HDB window requires an HDB renovation permit. Engage a BCA Approved Window Contractor listed with HDB to apply before the work starts. If the issue is a loose component, damaged frame or worn fitting, ask the contractor to inspect it and classify the work before accepting a replacement quote.
The rules for grilles depend on their location and the development. Service-yard or balcony-parapet grilles for flats handed over from 1 July 2007 generally require a permit and an approved design under HDB’s guidelines. A full-height, three-quarter-height or bay window can involve a safety barrier. Check that separately before ordering any work.
- Identify the exact window or grille and whether the work is repair, replacement or installation.
- Check the contractor’s BCA approval and HDB listing for window works.
- Verify any permit and approved design for the specific opening.
- If there is a risk of a window falling, keep people away and get urgent professional help.
Find the section you need
Chapters 1–3
Record the type, room and location
An ordinary bedroom sliding window, a casement window facing a corridor and a full-height window above a low sill can all be described as windows on a quotation. Their placement and construction are relevant to the rules. Start with the room, opening type, floor level and whether the opening faces a corridor, balcony or exterior wall. Photograph it from a safe position inside the flat if that can be done without operating a damaged part.
Ask the contractor to identify the work needed. A window that binds may have a worn fitting, a track issue or damage to the frame. A grille that has rusted can be separate from the frame, or part of an original safety arrangement. The diagnosis should describe which component is affected and what will be retained. It should also say whether the proposal amounts to replacement requiring a permit.
Check risk before arranging ordinary work
If a window appears unstable or at risk of falling, keep people away from it and the potential area below where possible. Do not force it open, lean out or attempt exterior work. Contact an approved contractor promptly and notify the relevant building authority or manager if there is a risk to people using a shared area. Give the location and explain whether the window is visibly loose or has already moved out of position.
For an old flat with several windows, write down which are urgent and which simply need inspection. The contractor can assess the other windows during the same visit. If somebody has already closed off an affected room, tell the contractor about the precaution and ask what is safe until the repair or replacement can happen. Avoid confusing a temporary measure with a permanent fix.
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Check both the approval and listing
HDB says to use a BCA Approved Window Contractor listed with HDB for window replacement and relevant window work. Verify the business and the person responsible for the work. If a general renovation company is quoting for the whole flat, ask who the approved window contractor will be and who will apply for any required permit. Keep the answer with the written scope.
Ask the contractor to identify each window by room and type. A quote should say what parts will be replaced and which will remain. For example, a package that replaces a moving panel but retains the frame differs from one involving the entire opening. Have the contractor explain the approval and compliance implications of each option and the basis for any additional charge.
Compare the same work across quotes
For each quote, check whether it includes inspection, permit handling, disposal, finishing and access. If the contractor expects further work once the frame is exposed, ask how it will be priced and approved. A cheaper initial amount may not cover an equivalent scope. Compare the final documents as well as the material description.
For a recently bought flat, the owner may want work to coincide with painting or other renovation. The window contractor and the other trades should agree who protects finishes and in what order the work happens. Work subject to a permit can only begin when the required approval is in place. A contractor’s availability is a separate matter from when the flat is ready and work can legally start.
If the flat is occupied, explain which rooms must remain usable and whether somebody will be home during the work. Ask what precautions the contractor will take near windows and in shared areas. Record a contact person for the day and a plan if weather or access requires the work to be postponed.
Ask which assumptions each quote makes
Take a set of three ordinary windows and one service-yard opening. A first quote describes all four as replacement windows. A second proposes repairing two frames and replacing one window while installing a grille in the service yard. Ask each contractor to mark the proposed work on the same room list. Where a replacement or grille permit is needed, ask who submits it and what design will be requested.
The homeowner can then compare how much work is actually being done. A repair can make sense if an approved contractor determines that the frame remains suitable. Replacement may be appropriate where the damage or the condition of the installation calls for it. Seek a written explanation if the proposals differ. In particular, ask whether the repair option addresses the problem that led you to call, such as loose movement or water entering at a particular point.
Check what is included in the finish after the work. Reinstatement around a window can affect paint, wall finishes or nearby cabinetry. Record who handles each part and when it will be done. If another contractor is responsible, discuss the order before work begins. Avoid allowing one contractor to alter the opening on the assumption that the other will later obtain a permit.
For a window near a balcony or corridor, ask how work will be controlled for people below or nearby. Let the approved contractor manage the work zone. Keep household members and pets away from the immediate area and ask when the room will be usable again. If dates change because a permit or component is pending, update both the contractor schedule and the family’s use of the room.
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Confirm the permit before replacement
HDB requires a renovation permit for window replacement. Its guidelines also specify matters such as matching the existing colour scheme, dimensions and window type where applicable. Ask the contractor to show the proposed work against the approved condition for the opening. Keep the permit and the approved scope, and follow HDB’s notice and timing instructions where applicable.
Changes that seem minor indoors can alter the façade or create an obstruction. HDB gives common-corridor casement windows as an example of disallowed work when the façade faces the common corridor. An attractive design in a brochure can therefore be unsuitable for a particular opening. Ask the contractor to verify the location and the restrictions before placing an order.
Check service-yard and balcony grilles separately
HDB distinguishes service-yard or balcony-parapet grilles for flats handed over from 1 July 2007 from certain internal grille arrangements in earlier developments. For the former, its guidelines list a permit and approved designs. Use the project’s renovation factsheet or MyHDB to check the actual pattern. For the earlier internal-grille category, HDB lists a permit-free arrangement subject to conditions, including that the grille is installed internally and does not protrude.
Do not use a grille approval to assume that glazing or enclosure is allowed. HDB restricts windows and certain forms of enclosure at specified open balconies and planter boxes. The correct answer depends on the opening and the development’s conditions. If the quote includes a screen, grille and glazing, ask the contractor to explain each separately.
Imagine a family fitting a service-yard grille to protect a pet. It should check the approved pattern, ask whether the proposed additional screen is permissible, and consider the appropriate way to secure it without altering prohibited elements. Confirm the permitted work before buying a custom-sized item that may be difficult to return.
| Work | What HDB says to check | First action |
|---|---|---|
| Replacing a window | Renovation permit required | Use a BCA Approved Window Contractor listed with HDB |
| Service-yard or balcony-parapet grille for handover from 1 July 2007 | Permit and approved grille design | Check the renovation factsheet or MyHDB |
| Specified internal metal grilles in developments handed over before 1 July 2007 | No permit under the listed conditions | Check location and façade restrictions |
| Full-height, three-quarter-height or bay window | Replacement restricted, with damage-related exception subject to approval | Request an assessment and verify the safety-barrier route |
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Ask whether a safety barrier is integrated
HDB generally disallows replacement of full-height windows, including three-quarter-height and bay windows, with a possible permission route if a damaged frame requires complete replacement. Some windows incorporate a safety barrier. A grille or railing originally provided for safety should be left in place unless the proper damage and approval route applies. Ask the approved contractor to identify the safety function from the records and actual opening.
If the contractor recommends replacement, ask why repair is insufficient and what evidence will support the application. Keep the photographs and written assessment. The fact that another flat installed a different design does not show that the same work is permitted at your opening.
Find the appropriate design and professional route
HDB describes a route using BCA’s standardised designs for qualifying replacement of integrated safety barriers. It has conditions on the firms and trained installers who can use it and requires completion certification under the stated process. If the standardised designs are unsuitable, a civil or structural Professional Engineer may be needed to design the works and submit plans. HDB describes additional approval and permit steps for that route.
Ask the contractor to identify the route, expected submissions and the person responsible for each. Check when the HDB permit and any BCA authorisation must be in place. A cost estimate should distinguish professional fees, work and reinstatement. The required drawings and completion records should be included in the handover.
A household that needs urgent attention should explain the risk immediately. Ask about safe interim precautions and what can be inspected without beginning unauthorised replacement. If the full scope takes time to approve, keep the interim instructions visible to anyone using the room.
Work through a full-height case before ordering anything
Imagine that a large window has damage around its frame and a safety barrier appears to form part of the system. The owner should first arrange an inspection by the appropriate contractor. Ask them to confirm the type of opening, what caused the concern and which part needs work. Take photographs only from a safe place and let the professional identify the condition of concealed components.
If complete replacement is proposed, ask whether HDB’s damage-related route is available and whether a BCA standardised design applies. A contractor who proposes one should be able to explain whether their team has the required training and what certification it will submit. If a Professional Engineer is needed, ask who appoints them, when the plans are prepared and what needs approval before any structural work starts. The order of these steps can affect the renovation schedule.
The new arrangement may have to match the original type, appearance and dimensions. An owner should avoid commissioning custom glazing before those requirements are confirmed. Ask who will check the original condition and what record supports it. If the seller altered the opening previously, ask HDB or the approved professional how to establish the correct basis for the application.
Keep the damage assessment, drawing and submission records with the quote. When a permit is issued, compare the actual approved scope with the work the contractor plans to do. If a different safety barrier or frame is proposed after measurements are taken, ask whether that changes the approvals. The time to settle this is before a safety component is removed.
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Look at common symptoms from indoors
HDB publishes maintenance guides for different kinds of windows. A change in how a window moves, obvious corrosion, a loose fitting or damage around a track is a reason to have the condition checked. Casement windows use supporting hardware that differs from a sliding window’s track and safety fittings. Describe what you have observed without operating a window that appears unstable.
BCA and HDB note the requirement to replace aluminium rivets in casement windows with stainless steel ones under the retrofitting order. If you recently bought the flat or have no service record, ask an approved contractor to check the relevant fittings and confirm what work is needed. Do not assume a recent coat of paint or a polished frame tells you what kind of rivets are present.
Make a practical inspection record
List every room and note whether a window was checked, repaired or replaced. Add the contractor’s observations and the date. If a contractor recommends inspecting a group of similar windows, ask how they will record the findings and prioritise work. The record is useful if several windows were installed at different times.
At resale, ask the seller for any available renovation permits, invoices and maintenance records. Bring an uncertain installation to the attention of the approved contractor or HDB. If the sale has yet to complete, discuss the issue with the relevant parties and follow the purchase process. Keep any agreement about access, rectification or handover in writing. A buyer who already has the keys can use the same information to plan inspection before other renovation covers the area.
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Compare the work to the approved scope
At handover, go through the list of openings with the contractor. Ask them to demonstrate operation from inside and explain the safety fittings and maintenance needs. Compare what was installed with the agreed type and appearance. If an opening was left for another visit, write down what remains and any interim precautions. Do not operate a window the contractor has asked you to leave closed.
Where certification or other documentation is required, confirm who will submit it and ask what copy you will receive. Keep the permit, contractor information, quotation, invoice and any drawings. A photo of the finished window can help identify it later, but keep the approval and completion evidence separately.
Decide how to follow up on a problem
If the window is stiff, a part feels loose or rain enters around the opening, report the exact window and when it happens. Ask what will be inspected and whether the work is under warranty. If it is a safety concern, treat it promptly and keep people away from the affected opening while seeking professional help. Avoid trying to fix an external fitting yourself.
Review the file after the first service or repair. Add the date and the parts changed. If the flat is sold later, the next owner can use those records to identify the contractor and the work approved for that window. It can also help the current owner avoid ordering a replacement based on a mistaken description of the existing system.
Use a room-by-room handover after a larger job
Create a row for each opening before the contractor arrives. Include the room, original type, proposed work and the documents you expect. On completion, ask the contractor to identify what was done and any components still outstanding. Where it is safe and appropriate, have the contractor demonstrate movement and locking from inside. Ask what warning signs require a service visit and whether there are maintenance instructions for the system.
If some work was approved under a different route, note it separately. The service yard may have an approved grille design, while a window elsewhere has an HDB replacement permit. A safety-barrier job may also have drawings and certification. Label the documents by opening so you can find the right one without relying on the contractor’s invoice number alone.
For example, a household may discover that one window was repaired during the project while the rest were replaced. If a problem appears months later, the row for that room tells the owner which contractor and scope apply. Ask whether the warranty covers the actual fitting and what evidence the company needs. If there is any risk of falling, seek prompt professional help rather than waiting for a routine service date.
When all work is complete, keep a copy of the final approvals and records somewhere the household can retrieve. A future buyer or contractor may need to identify whether a window is original, replaced or part of a safety system. Keep photos for identification, alongside the document that establishes the approved work.
Check the specific balcony before comparing design options
Begin with the type of balcony or service yard and the handover date. Confirm whether there is a parapet, a safety railing or an opening originally intended to remain unenclosed. Have the approved contractor compare the proposal with the flat’s renovation factsheet and HDB’s current guidance. If there is a conflict between a generic supplier drawing and the project’s approved design, obtain clarification before ordering.
One household might want an internal grille so that it can use the service yard with more confidence. Another might want to keep out rain with a new glass enclosure. Those are different projects, and the rules can differ for the same opening. Ask the contractor to mark each proposed element and explain which one requires approval, which design is permitted and which existing safety parts must stay in place. Do the same for any proposed screen.
For a flat with an open balcony, ask how the design preserves the required conditions for the opening. Some HDB guidance permits particular internal blinds under conditions while disallowing forms of permanent enclosure. The exact materials and placement matter. Do not treat a product description such as retractable or removable as proof that it is allowed. Give the contractor the precise proposal and confirm the applicable condition.
If the flat is a recent purchase, tell the contractor about any previous installations you cannot verify. Ask whether HDB records or the original project documents can establish the approved position. If something existing needs urgent attention, deal with the safety issue first and keep it separate from optional changes. That can prevent the replacement work from getting caught up in a broader redesign that has yet to be checked.
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Does replacing an HDB window need a permit?
HDB requires a renovation permit for window replacement. The approved window contractor listed with HDB applies before the work.
Does every grille need the same permit?
The rules depend on location and development. Check the specific guidance for the opening, including the handover date where relevant.
Can I change sliding windows to casement windows?
Check HDB’s conditions and the original window type. HDB may require matching the original and lists corridor-facing casement work among its examples of disallowed works.
Can I remove a safety railing integrated with a window?
HDB restricts removal and describes a specific process for damaged safety barriers that require replacement. Use an approved professional and check the applicable requirements.
What should I do if a window seems at risk of falling?
Keep people away, avoid operating it, and urgently contact an approved contractor. Notify the relevant building authority or manager if a common area is at risk.
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