By The Big Buy desk · Last verified 4 October 2026
Renovating an HDB flat in 2026 typically costs about S$50,000 to S$60,000 for a 4-room BTO and S$70,000 to S$81,600 for a 4-room resale flat, according to estimates by renovation platform Qanvast based on 341 BTO and 449 resale projects. Resale flats cost more because older homes need more hacking, rewiring and repairs. Whoever you hire, the firm doing the works must be listed on HDB’s Directory of Renovation Contractors (DRC). Choosing a CaseTrust-accredited renovation business adds deposit protection if the firm closes, a standard contract with clear payment stages, and access to the CASE Mediation Centre if things go wrong.
A renovation is often the second-biggest cheque after the flat itself. A clear budget, the right firm and a tight contract make it a joy rather than a saga.
Quick facts
- Typical 2026 costs: 3-room BTO about S$40,800 to S$52,500; 5-room BTO about S$60,600 to S$76,500.
- Resale flats typically cost roughly S$14,000 to S$22,000 more to renovate than BTO flats of the same size.
- Renovation contractors working in HDB flats must be listed on HDB’s DRC.
- HDB treats the renovation contract as a private arrangement between you and the firm.
- CASE says 97% of renovation complaints it received in 2024 were against non-accredited contractors.
- Unresolved disputes can go to CASE mediation or the Small Claims Tribunals.
Typical renovation costs by flat type (2026)
| Flat type | New BTO flat | Resale flat |
|---|---|---|
| 3-room | S$40,800 to S$52,500 | S$55,000 to S$68,300 |
| 4-room | S$50,000 to S$60,000 | S$70,000 to S$81,600 |
| 5-room | S$60,600 to S$76,500 | S$80,800 to S$98,900 |
Source: Qanvast’s 2026 estimates, built from its project data with 1% to 2% projected inflation. Your own quote depends on how much carpentry you want, whether you hack walls or redo bathrooms, and the finishes you choose.
Interior designer or contractor?
| Interior design (ID) firm | Contractor | |
|---|---|---|
| What you get | Design, 3D drawings, sourcing and project management | Building works to your own plans |
| Cost | Usually higher, as design and coordination are built in | Usually lower |
| Your workload | Lighter; the ID coordinates trades | Heavier; you decide details and may coordinate other trades |
| Best for | Resale overhauls, busy owners, full makeovers | Simple BTO jobs with a clear plan |
| Must-check | Works carried out by a DRC-listed firm; CaseTrust status | DRC listing; CaseTrust status |
Avoiding disputes: a step-by-step checklist
- Get at least three itemised quotes for the same scope, so you compare like with like.
- Check the firm on HDB’s Directory of Renovation Contractors and in CaseTrust’s list of accredited renovation businesses.
- Insist on a written contract with the full scope, materials, brands, drawings, start and end dates, and a payment schedule.
- Tie payments to completed stages, and avoid paying large sums upfront.
- Put every change in writing, with its price, before the work is done.
- Inspect at each stage and before the final payment, with a written list of defects to fix.
- If a dispute arises, raise it in writing, then use CASE mediation or the Small Claims Tribunals.
A worked example: staging payments on S$75,000
Here is one illustrative way to stage payments on a S$75,000 resale 4-room renovation. It is not a legal standard; agree your own schedule in the contract.
- On signing: 10%, S$7,500
- After hacking, masonry and plumbing: 40%, S$30,000
- After carpentry is installed: 40%, S$30,000
- After handover and defects fixed: 10%, S$7,500
- Total: S$7,500 + S$30,000 + S$30,000 + S$7,500 = S$75,000
Keeping the last 10% until defects are fixed gives both sides a clear finish line.
The WahLiao Verdict
Set your budget from the table above, then keep 10% aside for surprises, especially in a resale flat. Hire only a DRC-listed firm, and favour a CaseTrust-accredited one: the deposit protection and mediation access are worth far more than a slightly cheaper quote. Above all, get everything in writing and pay as the work is done, not before. A good renovation is one where nobody needs to remember who promised what.
Questions people ask
Does HDB help if my renovation contractor lets me down?
HDB regulates the works and can penalise DRC firms for breaking its rules, but price, schedule and quality disputes are a private matter between you and the firm. Use CASE mediation or the Small Claims Tribunals.
What does CaseTrust accreditation give me?
Protection for your deposit if the company closes or is wound up, a standard contract with clear work scopes and payment stages, and access to the CASE Mediation Centre.
Why does a resale flat cost more to renovate?
Older flats often need hacking, rewiring, new plumbing and repairs before the new finishes go in, which adds labour.
Do I need HDB approval for my renovation?
Some works need a permit, and noisy works must follow set hours. A DRC firm applies for permits; see our guide to HDB’s renovation rules.
Sources: Qanvast, expected renovation costs for HDB flats in 2026; HDB, Directory of Renovation Contractors; CASE, CaseTrust-accredited renovation businesses. The Big Buy explains; it does not advise.
Read next: HDB Renovation Rules: Permitted Hours, Noisy Works and Permits · Small Claims Tribunals: How to Claim Without a Lawyer · Back to The Big Buy
For what’s worth it this week, with the bill shown, read The WahLiao Week.
Leave a comment