If you are planning an HDB renovation in Singapore, the first question is usually the same: how much will it actually cost? For a 4-room flat in 2026, most homeowners spend between S$ 40,000 and S$90,000, depending on whether the flat is a new BTO or a resale unit and how much work is involved.

That is a wide range, so this guide explains what sits behind the numbers and where the money goes. It also covers how to keep your HDB renovation on budget. Whether you are doing a light refresh or a full overhaul, a clear plan makes home renovation in Singapore far less stressful.

Average 4-Room HDB Renovation Cost in 2026

Costs vary mainly by flat type and scope of work. Here is a realistic guide for 2026:

Flat typeTypical cost rangePremium 4-room BTO (new HDB)S$40,000–S65,000S$70,000+4-room resale HDBS$55,000–S90,000S$100,000+

These figures are indicative and based on typical 2026 market ranges. Your final quote depends on your layout, materials and designer, so always ask for an itemised quotation.

Why Is a Resale HDB More Expensive to Renovate?

A new BTO flat usually has a clean shell, so there is little to remove. A resale flat is different. It often needs hacking, rewiring, new plumbing and waterproofing, because the existing finishes may be 10 to 30 years old.

If you are buying second-hand, a dedicated resale HDB interior design and renovation service can help you work out what is worth replacing and what can stay. This is often where homeowners save the most money.

Where Does the Money Go? A Typical Cost Breakdown

Here is roughly how a 4-room HDB renovation budget is spent. The amounts are approximate and will shift with your choices.

Renovation itemEstimated costCarpentry (wardrobes, TV console, kitchen cabinets, shoe cabinet)S$12,000–S$25,000Hacking, tiling and waterproofingS$6,000–S$15,000Toilet renovation (per bathroom)S$4,000–S$8,000Electrical and lighting worksS$3,000–S$7,000PaintingS$1,500–S$4,000Flooring (vinyl, laminate or tiles)S$3,000–S$8,000Doors, windows and grillesS$2,000–S$6,000Air-conditioning and loose furnitureVaries widely

Carpentry is usually the biggest line item. Custom cabinets are popular because they make the most of limited space, but the cost climbs quickly with each extra unit.

What Affects the Cost of Your Renovation?

Several factors can move your budget up or down:

  • Scope of work. A paint-and-carpentry refresh costs far less than a full hack-and-rebuild.
  • Materials. Quartz worktops, solid wood and premium tiles cost more than standard finishes.
  • Design complexity. Curved features, feature walls and bespoke joinery add labour and time.
  • Layout changes. Moving walls or wet areas is costly, and some changes need HDB approval.
  • Who you hire. An interior design firm, a contractor and a DIY approach each carry different costs and risks.

HDB Rules You Should Know Before You Start

In Singapore, all renovation works must follow the HDB renovation guidelines. For example, you must hire an HDB-registered contractor for works that need a permit. Structural walls cannot be removed, and noisy work is only allowed during permitted hours.

It also helps to choose a firm that is CaseTrust-accredited or has a clear track record. Poor workmanship often costs more to fix than the original job.

Budgeting Tips for Your HDB Renovation

Planning ahead helps you avoid the most common budget problems.

  1. Set a total budget first, then allocate by priority. Kitchens, bathrooms and carpentry usually deserve the largest share.
  2. Keep 10% to 15% as contingency for unexpected issues such as hidden leaks or extra electrical work.
  3. Ask for a detailed quotation that lists materials, brands and quantities.
  4. Prioritise what is hard to change later, such as wiring, waterproofing and built-in carpentry. You can add furniture and décor over time.
  5. Think about how you live. A design that suits your daily routine avoids expensive changes later.

If you are paying through a renovation loan, remember that it counts towards your monthly debt commitments under the TDSR framework. It is sensible to check your repayment comfort before signing.

Ideas for Making a 4-Room Flat Feel Bigger

A well-planned layout can make a 4-room flat feel more spacious without extra cost. Light colours, built-in storage and smart zoning all help. For practical inspiration, these living room design tips for a 4-room HDB BTO show how to balance style, storage and comfort in a compact space.

Warm minimalism, curved details and a hidden home-office corner are among the most popular looks for 2026. All three suit smaller HDB homes well.

How Long Does a 4-Room HDB Renovation Take?

Most full renovations take around 10 to 14 weeks, from design approval to completion. Resale flats with heavy hacking may take longer. Delays usually come from late material deliveries, permit timing or mid-project design changes, so a clear scope from day one saves time.

Working With a Renovation Specialist

A good partner makes the process smoother and helps you spend wisely. Homescape Pte. Ltd. is a Singapore interior design and renovation firm with over 30 years of experience and more than 500 clients. Its in-house team handles design, masonry, carpentry, electrical works and tiling, with weekly progress updates throughout the project.

If you are comparing options for home renovation in Singapore, Homescape’s interior design and renovation services are worth exploring, and you can book a free consultation to get a clear, itemised quote for your flat.

Conclusion

A 4-room HDB renovation in Singapore can cost anywhere from S$40,000 to S$90,000 or more in 2026. The final figure depends on whether your flat is a new BTO or a resale unit, how much hacking and rewiring is needed, and how detailed your carpentry and finishes are. Knowing these factors early helps you set a realistic budget instead of being surprised halfway through the project.

Frequently Asked Questions

How much does a 4-room BTO renovation cost in Singapore in 2026?
Most homeowners spend about S$ 40,000 to S$65,000, depending on carpentry, materials, and design choices.

How much does a 4-room resale HDB renovation cost?
Typically S$55,000 to S$90,000. Resale flats cost more because of hacking, rewiring and waterproofing.

What is the difference between a BTO and a resale HDB flat?
A BTO flat is a new flat sold directly by HDB and built for you, while a resale flat is an existing flat bought from its current owner. BTO flats are usually cheaper to renovate because they need little hacking or repair.

Is a renovation loan available for HDB flats?
Yes, many banks offer renovation loans. Check the interest rate, tenure and your TDSR before committing.

Do I need HDB approval to renovate?
Some works, such as changing wet areas or altering certain structures, need a permit and an approved contractor. Always follow the HDB renovation guidelines.