Our picks for HDB interior design in Singapore in 2026 are Weiken, Carpenters and Starry Homestead, followed by Space Factor, Rezt+Relax and 9 Creation. We ranked them on HDB contractor registration, CaseTrust accreditation, safety and quality certification, years in business and warranty terms. HDB says you should engage contractors from its Directory of Renovation Contractors for renovation in your flat.
Facts come from each firm’s own website and from HDB, checked on 3 October 2026. No firm paid to be listed. Confirm any firm’s HDB registration on HDB’s e-service before signing.
At a glance
| # | Business | Best known for | Price |
|---|---|---|---|
| 1 | Weiken | CaseTrust Gold, ISO 45001 and BCA and HDB builder registration, operating since 1996 | On enquiry |
| 2 | Carpenters | HDB flats from 2-room Flexi to older resale, with permit-aware planning and itemised quotations | On enquiry |
| 3 | Starry Homestead | BTO, resale and HDB kitchen work from showrooms in Paya Lebar, Balestier and Boon Lay | On enquiry |
| 4 | Space Factor | A published HDB contractor number, HB-06-5311A, and CaseTrust-RCMA accreditation, in Eunos | On enquiry |
| 5 | Rezt+Relax | A lifetime carpentry hardware warranty that transfers to the next owner, with a dedicated BTO service | On enquiry |
| 6 | 9 Creation | A smaller HDB design studio at Tradehub 21 in Boon Lay, with 2020 HomeTrust awards | On enquiry |
What HDB renovation rules should I know before hiring a firm?
HDB says you should engage contractors from its Directory of Renovation Contractors (DRC) for renovation in your flat. Some works, such as demolishing walls, need HDB approval, and the renovation contractor submits the application with a floor plan of the proposed work.
HDB publishes separate guidelines for building works, window works, electrical works, aircon installation, and plumbing, sanitary and gas works. Window works use BCA-approved window contractors, which HDB lists through the same e-service. In practice this means your interior design firm should either be a DRC-registered contractor itself or work with one, and should handle the permit application. Ask the firm which works in your plan need a permit and who will submit it. Do not let work that needs approval start before the permit is granted.
How did we rank these interior design firms?
We gave most weight to stated HDB contractor registration: firms that state it come first. Within each group we then weighed CaseTrust accreditation, bizSAFE or ISO certification, years in business and a written warranty, all signals a homeowner can check. Design style is personal, so review portfolios of HDB projects similar to your flat.
- HDB registration: stated DRC or HDB registered contractor status.
- Consumer protection: CaseTrust or CaseTrust-RCMA accreditation stated on the firm’s site.
- Safety and quality: bizSAFE, ISO or BCA registration.
- Track record and warranty: founding year and stated warranty.
| # | Firm | Founded (stated) | HDB registration stated | CaseTrust | Other certification |
|---|---|---|---|---|---|
| 1 | Weiken | 1996 | BCA and HDB builders (2011) | CaseTrust Gold (2026) | bizSAFE STAR, ISO 45001 |
| 2 | Carpenters | 2010 | Listed in HDB’s DRC | CaseTrust-RCMA | BCA registered, bizSAFE Level 3 |
| 3 | Starry Homestead | About a decade | HDB-approved | CaseTrust Gold | BCA registered, RCMA member |
| 4 | Space Factor | Not stated | HDB registered contractor HB-06-5311A | CaseTrust-RCMA | Not listed |
| 5 | Rezt+Relax | 2000 | Not stated on page checked | CaseTrust-RCMA | ISO, BCA, Singapore Quality Class |
| 6 | 9 Creation | Not stated | Not stated | Not stated | HomeTrust awards (2020) |
How much does an HDB renovation cost?
None of the six firms publishes fixed renovation prices. Cost depends on flat size, whether it is a new BTO or an older resale flat, the amount of hacking and carpentry, and materials. The lowest budget option on enquiry forms is under S$30,000 at Weiken and S$40,000 at Space Factor.
An older resale flat may need old finishes, wiring or plumbing replaced, which a new BTO flat usually does not. Ask each firm for an itemised quotation that separates hacking, masonry, carpentry, electrical, plumbing, painting and design fees, so you can compare like for like. Ask how the deposit is protected and when progress payments are due.
Why is each firm on the list?
Each write-up summarises what the firm publishes and who it suits. Positions reflect our judgement against the criteria above.
Best known for: CaseTrust Gold, ISO 45001 and BCA and HDB builder registration, operating since 1996
Weiken has operated since 1996 and lists CaseTrust Gold accreditation for 2026, ISO 45001, bizSAFE STAR and registration as BCA and HDB builders since 2011. It designs HDB, BTO, condo, landed and commercial spaces from showrooms at Tradehub 21 in Boon Lay and CT Hub 2 on Lavender Street. Suits owners who want a long-established firm with full paperwork.
- Services
- Interior design and renovation for HDB, BTO, condo, landed and commercial spaces; space planning; project management
- Credentials
- CaseTrust Gold (2026); ISO 45001; BCA and HDB Builders (2011); bizSAFE STAR (2012)
- Address
- 18 Boon Lay Way #01-134, Tradehub21, Singapore 609966
- Founded
- 1996
Best known for: HDB flats from 2-room Flexi to older resale, with permit-aware planning and itemised quotations
Carpenters, founded in 2010, says it is listed in HDB's Directory of Renovation Contractors, CaseTrust-RCMA accredited, BCA registered and bizSAFE Level 3. Its HDB work covers new 2-room Flexi to 5-room BTO flats and older resale flats, with permit-aware planning and itemised quotations. Showrooms are in Ubi and Boon Lay. Suits HDB owners who want a firm focused on flats.
- Services
- HDB BTO and resale renovation, space planning, custom carpentry, permit-aware planning
- Credentials
- Listed in HDB Directory of Renovation Contractors; CaseTrust-RCMA; BCA registered; bizSAFE Level 3 (as stated)
- Address
- 62 Ubi Road 1, #01-01, Oxley Bizhub 2, Singapore 408734
- Founded
- 2010
Visit website: CarpentersCall +65 8774 8495Full profile: Carpenters
Best known for: BTO, resale and HDB kitchen work from showrooms in Paya Lebar, Balestier and Boon Lay
Starry Homestead describes itself as CaseTrust Gold accredited, HDB-approved, BCA-registered and an RCMA member, and lists QanVast SuperTrust awards from 2016 to 2026. It handles BTO and resale flats and HDB kitchens, with showrooms in Paya Lebar, Balestier and Boon Lay. Suits owners who want a showroom near home.
- Services
- BTO and resale flat renovation, HDB kitchen design, interior design
- Credentials
- CaseTrust Gold; HDB-approved; BCA-registered; RCMA member (as stated)
- Address
- 18 Boon Lay Way, #01-101, Tradehub 21, Singapore 609966
Visit website: Starry HomesteadCall +65 6778 6866Full profile: Starry Homestead
Best known for: A published HDB contractor number, HB-06-5311A, and CaseTrust-RCMA accreditation, in Eunos
Space Factor publishes its HDB registered renovation contractor number, HB-06-5311A, and lists CaseTrust-RCMA accreditation. It offers HDB interior design from its office at Richfield Industrial Centre, Eunos. Publishing the registration number makes it easy to check. Suits owners who want to verify credentials quickly.
- Services
- HDB interior design, renovation
- Credentials
- HDB Registered Renovation Contractor HB-06-5311A; CaseTrust-RCMA (as stated)
- Address
- 122 Eunos Avenue 7 #08-02/03, Richfield Industrial Centre, Singapore 409575
Visit website: Space FactorCall +65 6746 0082Full profile: Space Factor
Best known for: A lifetime carpentry hardware warranty that transfers to the next owner, with a dedicated BTO service
Rezt+Relax, founded in 2000 and based at T-Space in Tampines, lists CaseTrust-RCMA accreditation, ISO certification, BCA certification and the Singapore Quality Class award. It offers a lifetime warranty on carpentry hardware mechanisms that it says transfers to the next owner, and has a dedicated HDB BTO service. Suits buyers who care about after-sales cover.
- Services
- Interior design, HDB BTO renovation, lifetime warranty on carpentry hardware
- Credentials
- CaseTrust-RCMA; ISO certified; BCA certified; Singapore Quality Class
- Address
- 1 Tampines North Drive 1, #01-08, T-Space, Singapore 528559
- Founded
- 2000
Visit website: Rezt+RelaxCall +65 6348 7787Full profile: Rezt+Relax
Best known for: A smaller HDB design studio at Tradehub 21 in Boon Lay, with 2020 HomeTrust awards
9 Creation, at Tradehub 21 in Boon Lay, has a dedicated HDB interior design service and displays 2020 HomeTrust awards for design, workmanship and customer service. Its site did not list HDB registration or CaseTrust when we checked, so ask for both. Suits owners in the west who want to compare a smaller studio.
- Services
- HDB interior design, renovation
- Address
- 18 Boon Lay Way, Tradehub 21, #01-98A, Singapore 609966
Visit website: 9 CreationCall +65 9199 9533Full profile: 9 Creation
Frequently asked questions
Does my interior designer need to be HDB-registered?
HDB says you should engage contractors from its Directory of Renovation Contractors for renovations in your flat. If your designer is not registered, ask which registered contractor will carry out the work.
Do I need a permit to renovate my HDB flat?
Some works do, such as demolishing walls. The renovation contractor submits the application to HDB with a floor plan of the proposed work. Check HDB’s renovation guidelines for each type of work.
What is CaseTrust-RCMA?
It is a CaseTrust accreditation scheme for renovation firms. Several firms on this list state they hold it. Ask the firm for its current certificate and how your deposit is protected.
How many quotes should I get?
Get itemised quotes from at least two or three firms using the same floor plan and scope, so differences in price reflect the work, not the brief.
How did you rank these firms?
We weighed HDB registration, CaseTrust, certification, track record and warranty, using only what each firm publishes. We update the list when those facts change.