HDB Renovation Rules 2025: What You Can and Cannot Do to Your Flat

Why HDB Renovation Rules Matter More Than You Think

Every year, HDB receives thousands of complaints and investigates hundreds of cases involving unauthorised renovation works. The consequences range from fines of up to S$5,000 per offence to mandatory reinstatement — meaning you pay to demolish the illegal works and restore the flat to its original condition. In severe cases, HDB can even take action against the flat owner's tenancy.

Yet most homeowners who fall foul of these rules did not set out to break them. They simply did not know what was and was not allowed. This guide is your definitive reference for HDB renovation rules in 2025.

The Renovation Permit: Your Starting Point

The HDB Renovation Permit is the central mechanism through which HDB controls renovation works. It is applied for by your registered contractor or ID firm through the HDB Renovation Contractor System (HRCS). As a homeowner, you should request a copy of the approved permit before any works begin — this document specifies exactly what has been approved.

Works requiring a permit include: demolition or hacking of any wall, installation of floor finishes, bathroom and toilet renovation (including waterproofing), electrical rewiring, aircon installation, installation of entrance gates and grilles, and any works affecting the building's external facade. Works that do not require a permit include interior painting, installation of furniture and built-in carpentry that does not involve hacking, and minor fixture replacements.

Structural Walls: The Absolute No-Go Zone

This is where most serious violations occur. HDB flats have two types of walls: structural RC (reinforced concrete) walls and non-structural partition walls. Only non-structural walls may be hacked, and only with a permit.

How do you tell them apart? RC walls are typically 150mm to 200mm thick and contain steel reinforcement. They appear on the structural plan of your flat, which you can obtain from HDB. Partition walls are usually 75mm to 100mm thick and are made of lighter materials like brickwork or drywall. When in doubt, your contractor should check with a structural engineer — HDB can also advise.

You absolutely cannot: hack through RC walls, remove structural beams or columns, cut openings in load-bearing walls for doors or windows, or do anything that compromises the structural integrity of the building. These rules apply regardless of what any contractor tells you, and HDB inspectors do check.

Wall Types at a Glance

Wet Areas: Bathrooms, Toilets, and Kitchens

Wet area renovation is subject to strict waterproofing requirements because poor workmanship in these areas causes water seepage into neighbouring flats — a major source of neighbour disputes in Singapore. HDB requires that all wet area floors and walls (to at least 300mm above floor level) be properly waterproofed before tiling.

For the open concept kitchen trend that has taken Singapore by storm, there are additional considerations. HDB allows homeowners to remove the kitchen wall to create an open plan layout, but the kitchen must still have a door or some form of separation to contain cooking fumes. A glass panel or sliding door is a common solution. The wet kitchen (cooking area) must remain enclosed to prevent grease and smoke from spreading into common areas and neighbouring units.

The bomb shelter, present in most HDB flats built after 1997, has its own set of rules. You may use it as a storeroom or study, but you cannot: seal it permanently, alter its ventilation, obstruct its entrance, or carry out any structural modifications. The bomb shelter door must remain functional and unobstructed at all times.

"We thought removing the kitchen wall would be straightforward, but our ID flagged that one side was an RC beam soffit we couldn't touch. The workaround she proposed — a partial opening with a glass panel — actually looked better than full removal would have." — Homeowner, 5-room resale flat, Bishan

Noise Restrictions and Renovation Hours

Noisy renovation works are restricted to specific hours under HDB's guidelines and the Environmental Protection and Management Act (EPMA):

• Monday to Friday: 9am to 6pm (noisy works); up to 10pm for non-noisy works
• Saturday: 9am to 1pm (noisy works); up to 10pm for non-noisy works
• Sunday and Public Holidays: No renovation works allowed

Noisy works include hacking, drilling, grinding, and the use of power tools. Neighbours who are disturbed can call the HDB Branch or NEA. Repeat offenders can face fines and Stop-Work orders. Make sure your contractor knows these rules and adheres to them — it is your responsibility as the flat owner.

Flooring: Rules That Catch Homeowners Off Guard

Flooring renovation is one of the most common sources of HDB violations because homeowners do not realise it requires a permit. Key rules include:

• New floor finishes can only be laid over the original floor finish — you generally cannot hack up the original screed, which would affect the floor's soundproofing between units.
• Floor loading limits must be observed — heavy materials like thick marble slabs across large areas may require structural assessment.
• Timber flooring is popular but must be installed with acoustic underlay to reduce impact noise transmitted to the unit below.
• In wet areas (kitchen, bathrooms), floor tiles must be slip-resistant (R9 rating minimum as per Singapore standards).

Popular Flooring Choices and HDB Compliance

• Homogeneous tiles: Fully compliant; R9 slip-resistance rating required in wet areas
• Luxury vinyl planks (LVP): Compliant when laid over existing floor without hacking; acoustic underlay recommended
• Engineered timber: Compliant; acoustic underlay required; check floor loading if using thick boards
• Natural marble/stone: Compliant but check floor loading; specialist installer required for natural stone

Windows, Grilles, and External Works

Any works affecting the external facade of the building — including window replacement, installation of grilles, and changes to the balcony — require HDB approval. Window grilles are among the most frequently violated rules:

• All window grilles must have at least one hinged or sliding panel that can be opened from inside without a key, for emergency egress.
• Grille designs must not protrude beyond the external wall face.
• You cannot install fixed security mesh over windows in a way that would prevent escape during an emergency.
• The main entrance gate must comply with HDB's approved designs and cannot extend beyond the flat boundary.

Electrical Works: Safety First

All electrical works in HDB flats must be carried out by a Licensed Electrical Worker (LEW) registered with the Energy Market Authority (EMA). This is a legal requirement under the Electricity Act, not just an HDB rule. Your contractor must obtain an electrical permit, carry out the works, and have them inspected and certified before energisation.

Common electrical works that require proper licensing: adding new power points or circuits, relocating the distribution board (DB box), installing new lighting circuits, and wiring for air-conditioning. Do not let any contractor do electrical works "off the record" — faulty electrical installations are a fire hazard and void your home insurance.

What Happens If You Are Caught with Unauthorised Works?

HDB conducts routine inspections and also responds to complaints from neighbours. If unauthorised works are found, HDB will issue a Notice to Reinstate, requiring you to remove the unauthorised works and restore the flat to its approved condition — at your own expense. Fines of up to S$5,000 per offence may also be imposed. In egregious cases involving structural works, HDB can take stronger legal action.

If you have purchased a resale flat and discover the previous owner carried out unauthorised works, you become responsible for rectifying them. This is why a thorough pre-purchase inspection — and checking with HDB for any outstanding notices — is essential before buying a resale flat.