Renovating an HDB bathroom: the rules
Part of the questions on HDB renovation rules and permits
In a newly built HDB flat, the wall and floor finishes in bathrooms and toilets must not be replaced for 3 years from the completion date of the block; new tiles can be laid over them instead. After that, replacing the finishes or enlarging the room needs an HDB permit, with new waterproofing and a water test.
The 3-year rule
HDB lays a waterproofing membrane on the cement screed under the toilet floor, so that water does not leak into the ceiling of the flat below. For that reason the toilet floor and wall finishes provided by HDB or the developer must not be replaced for 3 years from the completion date of the block. This is from HDB’s Important Information on Renovations.
The 3 years run from the completion of the block, not from the day you collect your keys. In the meantime, HDB says, new toilet floor finishes may be laid over the existing ones using adhesives. HDB’s MyNiceHome guide puts it as overlaying the original tiles with tiles of your choice in place of hacking them away.
What needs a permit, and what does not
| Work | Permit | HDB’s conditions |
|---|---|---|
| Replacing the bathroom or toilet wall finishes, after the first 3 years | Yes | No tampering with existing structures. Wall finishes, plaster included, no more than 25 mm thick in total. Pre-packed material for plastering. |
| Replacing the bathroom or toilet floor finishes, after the first 3 years | Yes | Finishes and screed no more than 50 mm thick in total. Pre-packed waterproofing screed and a waterproofing membrane before the new finishes. |
| Enlarging the bathroom or toilet, after the first 3 years | Yes | The extension no more than 600 mm wide and 0.6 m² in area, and for use as a dry area only, for example for a wash basin or shelves. The gas riser and its branch pipe must not end up enclosed in it. |
| Replacing the bathroom or toilet vent | Yes | Glass louvres at least 6 mm thick and of the wire-glass type, with an aluminium U-channel cleat safety device on every louvre. |
| Raising the floor with lightweight screed or blocks | Yes | The in-fill material must be non-combustible. |
| A cement mortar kerb no more than 100 mm high and 100 mm wide | No | |
| A sliding glass door or PVC folding door at the bathroom entrance | No | Provided the reinforced concrete lintel or hanger, if there is one, is not removed. |
These rows are from HDB’s Renovation Guidelines for Building Works. A glass shower screen does not need HDB’s approval either, MyNiceHome says, as long as the floor slab is not tampered with when it is installed. How to apply is in the HDB renovation permit.
When the floor is redone
- Pre-packed waterproofing screed and a waterproofing membrane must be used before the new floor finishes are laid.
- The membrane should be turned up at least 150 mm against the walls, kerbs and pipes.
- A UPVC floor trap grating with a long collar must be used at the floor traps.
- You and your renovation contractor must conduct a water test on the bathroom or toilet once the floor finishes have been replaced.
- Removing floor and wall finishes is noisy work: weekdays only, 9am to 5pm. See HDB renovation hours and rules.
What is not allowed
Among HDB’s examples of disallowed sanitary and plumbing work is constructing a water tank in the bathroom, other than using a ready-made long bath, such as a fibreglass one. HDB also asks owners to check MyHDB Page for any renovation guidelines specific to their own flat.
Sources
- HDB, Renovation Guidelines for Building Works · read 12 October 2026
- HDB, Important Information on Renovations · read 12 October 2026
- MyNiceHome (HDB), How to Renovate Your HDB Flat, updated 24 June 2026 · read 12 October 2026
Rules and fees change. The linked page is the authority; if it differs from this one, go by it, and tell us.
Questions
Can I hack the toilet tiles in a new BTO flat?
Not for the first 3 years from the completion date of the block. HDB does not allow the toilet floor and wall finishes it provided to be replaced in that time, to protect the waterproofing. New tiles can be laid over the existing ones.
Do I need a permit to change bathroom tiles in an HDB flat?
Yes, to replace the existing wall or floor finishes, which is allowed after the first 3 years from the completion of the block. HDB’s conditions include new waterproofing under the floor and limits on the thickness of the finishes.
Can I make my HDB bathroom bigger?
A little, with a permit, after the first 3 years. HDB allows an extension of no more than 600 mm in width and 0.6 m² in area, to be used only as a dry area, for example for a wash basin or shelves.
Is a water test required after redoing an HDB toilet floor?
Yes. HDB’s technical terms say you and your renovation contractor must conduct a water test on the bathroom or toilet upon completing the replacement of floor finishes.
Plan the bathroom you can build: tile the walls and floor on your own plan, and see what it comes to.
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