Short answer: Qanvast's 2026 projections put resale HDB renovations at about $55,000 to $68,300 for a 3-room flat, $70,000 to $81,600 for a 4-room and $80,800 to $98,900 for a 5-room. That is noticeably more than a BTO flat, because a resale renovation pays to remove and repair before it pays to build.

Resale HDB renovation cost by flat type (2026 estimates)

  • 3-room resale: about $55,000 to $68,300
  • 4-room resale: about $70,000 to $81,600
  • 5-room resale: about $80,800 to $98,900

These are projections from project medians on Qanvast, not official figures. For comparison, its 4-room BTO range is about $50,000 to $60,000. Other guides estimate resale renovations at 20 to 40% more than equivalent new flats. Read our BTO cost guide for how those figures break down.

The hidden works that push resale costs up

A new flat starts from a clean slate. A resale flat starts with someone else's choices, plus years of wear. These are the items new-flat budgets miss:

1. Demolition and disposal

Old carpentry, tiles, false ceilings and sometimes walls need to come out first, and the debris has to be removed. This is labour-heavy and often quoted as a lump sum, so ask what it covers.

2. Rewiring

Older flats may have wiring that is not suited to modern loads such as induction hobs, ovens and multiple air-conditioners. Rewiring is much cheaper while walls are open than after you move in. Electrical works must be done by an EMA licensed electrical worker.

3. Plumbing replacement

Old pipes can corrode or leak. Replacing concealed pipes during the renovation avoids hacking new tiles later. Water and sanitary works need a PUB licensed plumber.

4. Bathrooms and waterproofing

Resale bathrooms are often fully redone: hacking tiles, new waterproofing, new tiles and fittings. With a permit, this is allowed for older flats, and the waterproofing is the part not to cut corners on.

5. Windows and doors

Old windows may need repair or replacement, which must be done by a BCA Approved Window Contractor. Main doors and gates are also common replacements.

6. Surprises behind the surface

Uneven floors, hollow tiles, damp walls or ceiling defects only show up once works start. This is why a contingency matters more for resale than for BTO.

Check before you plan: upgrading programmes

If your block is old enough, HDB may carry out upgrading works such as the Home Improvement Programme, which can include bathroom upgrades. Check your block's status with HDB before spending on bathrooms that might be redone.

How to budget a resale renovation

  1. Inspect before you finalise your scope. Note every problem in the flat so the quotation covers fixing it, not just decorating over it.
  2. Separate "must fix" from "nice to have". Wiring, plumbing and waterproofing come before feature walls.
  3. Keep a 10 to 15% contingency. Guides commonly recommend this for unforeseen works found during hacking.
  4. Ask for itemised quotes. Lump sums for demolition or electrical works make it hard to compare and easy to add variation orders later.
  5. Reuse what works. Some resale flats have solid flooring or carpentry worth keeping and refinishing.

Character-rich styles often suit resale flats well. Have a look at the Retro, Peranakan and Rustic concepts for ideas.

How JIAHOME helps

We plan your resale renovation in 2D and 3D first and give you an unpriced quotation listing every item, including the repair works. Contractors then quote on the same scope, so the "hidden" works are visible from day one. See our packages.

Last updated 14 October 2026