HDB flats are shared structures — which is why more renovation work needs written approval than most homeowners expect. Here’s what to know before the first hammer swings.
By Alderic Tan · 3dots · Updated 15 August 2026
Quick answer
Work that touches structure, layout, waterproofing or fire safety needs an HDB renovation permit. Purely cosmetic work generally does not.
The permit must be obtained before work starts. It cannot be applied for retroactively.
Only contractors listed on HDB’s Directory of Renovation Contractors may carry out the work or submit the application on your behalf.
Load-bearing walls, columns, beams and household shelters are never approved, and new BTO bathrooms cannot be hacked for 3 years from TOP.
Some things will never get a permit, regardless of your design:
Your flat’s floor plan indicates structural walls — usually shown as thicker or bolded lines. Always confirm with your contractor before assuming a wall is safe to remove.
New BTO flats carry an additional restriction: bathroom and toilet wall and floor tiles cannot be hacked for 3 years from TOP, to let the waterproofing membrane fully cure. This isn’t a grey area — hacking within that window is unauthorised work, and HDB can levy fines on top of the reinstatement cost. Within the 3 years, you can still repaint, swap sanitary fittings, or overlay new tiles — you just can’t strip the originals down to the membrane.
It also isn’t just a permit rule — HDB’s original waterproofing comes with its own 3-year warranty against leaks. Hacking early voids that warranty immediately, and can also draw a fine of up to S$5,000 on top of the reinstatement cost, even if no visible damage occurs on the day. If a leak shows up afterwards, whether into your own flat or the ceiling below, rectification becomes the homeowner’s cost rather than HDB’s. Overlaying new tiles on top of the originals, by contrast, is fully HDB-compliant — it keeps the warranty intact and needs no hacking permit, so it’s the standard route within the 3-year window. Whichever route you take, always get your contractor’s written confirmation that the plan is HDB-compliant for your flat before work starts.
Even approved work is bound by hours to protect neighbours:
Unauthorised hacking or structural work can result in fines and a mandatory reinstatement order — meaning you pay to undo the work and restore the flat, on top of the fine. It’s a costly, avoidable mistake. The safest approach is simple: confirm every item of scope with your contractor against HDB’s current guidelines before committing to a design.
We work only with HDB-registered contractors, prepare and submit every application on your behalf, and don’t schedule hacking or wet works until approval is confirmed in writing. You focus on the design decisions — we handle the paperwork.
Tell us what you have in mind and we’ll tell you plainly what’s allowed — no obligation.
This guide summarises general HDB renovation rules and is not a substitute for HDB’s official guidelines, which can change. Always confirm current requirements with HDB and your registered contractor before starting work.
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