HDB Hacking Rules: What You Can and Can't Hack

In an HDB flat you can hack most non-structural partition walls, but only after HDB approves the work through a renovation permit, and only if a HDB-licensed renovation contractor carries it out. You can never hack structural walls, reinforced concrete (RC) walls, columns, beams, or the ductwork and bomb shelter (household shelter) that keep the block safe. When in doubt, treat a wall as off-limits until HDB confirms otherwise.

Hacking is one of the most common early steps in a renovation, and it is also one of the most tightly controlled. HDB rules exist to protect the building's structure, your neighbours, and yourself. This guide explains what you can hack, what needs a permit, what is strictly banned, and how the approval process actually works for a Singapore homeowner.

What can you hack in an HDB flat?

You can generally hack non-load-bearing partition walls, such as the light hollow or brick walls that separate a bedroom from a living area, or the wall around a store room. These walls carry only their own weight and do not hold up the flat above, so removing them to open up a space is usually allowed with a permit.

You may also demolish existing built-in features from a previous renovation, such as old cabinets, false ceilings, floor tiles, and non-structural planter boxes, again subject to HDB conditions.

• Non-load-bearing partition walls between rooms
• Old built-in wardrobes, cabinets and vanity counters
• Existing wall and floor finishes such as tiles and screed
• False ceilings and bulkheads from a prior renovation
• Non-structural bedroom or store room walls (with permit)

What can you never hack in an HDB flat?

Structural elements are permanently off-limits because they hold up the entire block. This includes reinforced concrete (RC) walls, columns, beams, and the floor slab. Hacking any of these is illegal and dangerous, and HDB will not approve it under any circumstances.

The household shelter, often called the bomb shelter, is also fully protected. You cannot hack its walls, ceiling, or floor, remove its steel door or ventilation plate, drill deep into its surfaces, or seal it off. Common service ducts, refuse chutes, and the parapet or facade walls are similarly protected.

• Reinforced concrete (RC) structural walls, columns and beams
• The household shelter (bomb shelter) walls, door and ventilation plate
• Floor slabs and any part of the load-bearing structure
• Common ducts, refuse chutes and service risers
• External facade, parapet and window walls

How do I know if a wall is structural or not?

The most reliable source is your flat's approved structural plan, which shows RC walls in a distinct hatching. HDB can provide these details, and many owners request them before finalising a design. A HDB-licensed contractor or a Professional Engineer can also read the plan and confirm which walls are load-bearing.

As a rough rule of thumb, RC walls tend to be thicker and feel solid and dense when knocked, while hollow partition walls sound lighter. That said, do not rely on knocking alone. A wrong guess can compromise the building, so always verify against the official plan before any hacking begins.

Do I need an HDB permit to hack a wall?

Yes. Any hacking of walls, floors, or fixtures in an HDB flat requires a renovation permit, and the application must be submitted by a contractor listed under HDB's Directory of Renovation Contractors. Homeowners cannot apply for the permit themselves, and starting work without one can lead to enforcement action and orders to reinstate.

Permits typically take a few working days to process, and certain works carry conditions, such as restricted hacking hours and the removal of debris through approved routes. Your contractor should handle the submission, display the permit on site, and keep the works within what HDB has approved.

What are the rules on hacking hours and noise?

HDB limits noisy renovation work, including hacking and drilling, to weekdays and Saturdays, generally between 9am and 5pm. General noisy work is not allowed on Sundays and public holidays, and the most disruptive demolition activity is usually confined to the first weeks of the project.

These timing rules protect your neighbours and are enforced. Informing the neighbours before you start, and keeping heavy hacking to the permitted window, goes a long way toward a smoother renovation without complaints.

How much does HDB hacking and demolition cost?

Costs vary with the amount of hacking, the type of surface, and how much debris must be cleared. Hacking a single partition wall is far cheaper than stripping an entire flat back to bare structure, and disposal fees rise with the volume of rubble. Because every flat differs, it is best to get an itemised quote rather than rely on a flat figure.

This is work worth handing to a HDB-licensed team. On our hacking and demolition service page we break down what drives the price and how the permit and debris removal are handled, so you can plan the budget before committing. A proper contractor will also confirm which walls are safe to touch before quoting.

Frequently asked questions

Can I hack the wall between my kitchen and living room? Only if that wall is non-load-bearing and HDB approves it. Many older flats have a structural wall in this area, so it must be checked against the approved plan first, and an open concept may require keeping part of the wall or a beam.

Is it legal to remove or seal the bomb shelter? No. The household shelter is protected by law. You cannot hack, seal, or alter its walls, door, or ventilation plate, though you may use the room for storage as long as it stays fully accessible.

Can I hack my flat myself to save money? No. Hacking must be done by a contractor from HDB's approved directory, who also applies for the permit. DIY hacking is not permitted and risks fines and reinstatement orders.

What happens if I hack without a permit? HDB can require you to stop work, reinstate the flat to its original condition at your own cost, and take enforcement action. Always secure the permit before any hacking starts.