8 Best Interior Design & Renovation Firms in Singapore 2026 — HDB BTO, Resale & Condo (Costs + How to Vet)

TYPICAL 2026 BALLPARK RANGES (these vary hugely by scope, materials, carpentry volume, and finish level — treat as a starting reference, not a quote): HDB BTO (new flat, minimal hacking needed): 3-room ~S$35,000-50,000; 4-room ~S$45,000-65,000; 5-room / executive ~S$55,000-80,000. RESALE FLATS: typically 30-50% MORE than an equivalent BTO — because older flats need more hacking, full rewiring, replumbing, possible structural/waterproofing works, and removal of the previous owner's fittings. A 4-room resale can easily run S$60,000-90,000+. CONDOS: highly variable — ~S$60,000-120,000+ depending on size, whether it's new (developer-finished, less work) or resale, and the finish level; high-end condo + landed projects go well beyond. WHAT DRIVES THE NUMBER: (1) CARPENTRY is usually the single biggest line item (built-in wardrobes, kitchen cabinets, feature walls) — more carpentry = more cost. (2) HACKING + masonry (removing walls, re-tiling). (3) Electrical rewiring + additional points. (4) Material/finish tier (laminate vs quartz vs sintered stone, etc). (5) Whether you need new windows, aircon, or sanitary ware. MONEY-SAVING LEVERS: keep existing layout (avoid hacking walls), reduce custom carpentry (use freestanding furniture), choose mid-tier materials, and don't over-spec rooms you'll rarely use. BUDGET BUFFER: always hold back 10-15% contingency for variation orders + surprises (especially in resale flats where hidden issues surface once hacking starts). Get the written quote and compare scope line-by-line across 2-3 firms — the lowest bottom-line number often just means items were left out.

THIS IS THE MOST IMPORTANT PART — renovation horror stories almost always trace back to skipped due diligence. THE VETTING CHECKLIST: (1) HDB LICENSING — for HDB flats, the contractor must be on HDB's Directory of Renovation Contractors (DRC). Hacking + structural-related works require an HDB-licensed renovation contractor; using a non-listed contractor for HDB works can mean penalties + you bear liability. Check the directory on HDB's website. (2) CASETRUST-RCMA ACCREDITATION — look for firms jointly accredited under CaseTrust + the Renovation and Decoration Advisory Centre (RCMA). Accredited firms use a STANDARD RENOVATION CONTRACT, must follow a prescribed deposit-payment structure, and carry deposit performance protection — a major safety net if the firm folds mid-project. (3) QANVAST TRUST PROGRAM — if you source through Qanvast, its Trust Program holds your renovation payments and releases them to the firm by completed milestone (plus insurance coverage up to a cap). This is one of the strongest protections against a firm taking your deposit and disappearing. (4) PAYMENT SCHEDULE — insist on milestone-based payments tied to completed stages; NEVER pay a large lump sum upfront. A common red flag is a firm demanding 50%+ before work meaningfully starts. (5) WRITTEN CONTRACT — every item, material, dimension, and brand spelled out; verbal promises are worthless. (6) REVIEWS + COMPLETED PROJECTS — read recent Google/Qanvast reviews (look for project-management + after-sales complaints, not just pretty photos), and ask to see completed projects in your flat type. (7) THE ACTUAL DESIGNER — at larger firms, your assigned designer matters more than the brand; vet their personal portfolio. RED FLAGS: pressure to sign 'today only' deals, reluctance to put things in writing, no fixed address/showroom, quotes far below everyone else (corners will be cut), and large upfront deposits. Get 3+ quotes minimum.

THEY'RE DIFFERENT THINGS: (1) INTERIOR DESIGNER / ID FIRM — provides DESIGN (concept, 3D visuals, material + layout selection, styling) AND usually manages the build by coordinating contractors on your behalf (design + project management + carpentry). You pay for design expertise + a single point of accountability. Best for: owners who want a cohesive designed result and don't want to manage trades themselves (most BTO/condo owners). All 8 firms in this list are ID firms / design-build outfits. (2) RENOVATION CONTRACTOR — executes the physical works (hacking, masonry, electrical, plumbing, tiling, carpentry) but typically does NOT provide design direction. Cheaper if you already have a clear design + are willing to project-manage + source materials yourself. Best for: experienced owners, simple refreshes, or those on a tight budget who'll do the design legwork. For HDB flats the contractor must be HDB-listed regardless. (3) QANVAST — is NOT a firm; it's a DISCOVERY PLATFORM / marketplace that helps you find + shortlist ID firms, browse real completed projects + reviews, request quotes from multiple firms, and (crucially) use the Qanvast Trust Program for milestone-based payment protection. Think of it as the matchmaker + escrow layer, not the renovator. WHICH DO YOU NEED: most Singapore homeowners doing a full BTO/resale/condo renovation want an ID FIRM (design + build + accountability), and the smart move is to FIND that firm through Qanvast (to compare options + get Trust Program protection). Go direct-to-contractor only if you have the design sorted and the time/expertise to project-manage. PRO TIP: you can use Qanvast to shortlist 3-5 firms, get quotes, then engage the ID firm directly through the platform to keep the Trust Program protection.

RENOVATION DURATION (from works commencing, not from first enquiry): HDB BTO (new flat, minimal hacking) typically 6-10 weeks; RESALE flats 10-16+ weeks (more hacking, rewiring, waterproofing + potential surprises add time); CONDOS vary widely with size + scope. Add buffer time — variation orders, material delays, and defects-rectification routinely push timelines. WHEN TO START ENGAGING FIRMS: begin 2-3 MONTHS BEFORE your key collection / move-in target. The realistic sequence: (1) 2-3 months out — research + shortlist firms (use Qanvast), browse portfolios, read reviews. (2) Get quotes from 3-5 firms + meet the designers (this alone takes 2-4 weeks of back-and-forth). (3) Compare quotes line-by-line, negotiate, choose. (4) Design + 3D + material selection + contract signing (2-4 weeks). (5) Then the build (6-16+ weeks per above). FOR HDB BTO SPECIFICALLY: you can only start renovation AFTER key collection, but you should engage your firm + finalise the design BEFORE keys so works can start immediately — popular firms + designers book out, especially around peak BTO completion waves. Engaging late = either waiting for your preferred designer or settling for whoever's free. ALSO: HDB has rules on renovation timeframes + permitted hours (generally no noisy/hacking works on Sundays + public holidays, and restricted hours otherwise) — your HDB-listed contractor handles the permits, but confirm. PRO TIP: don't sign with a firm before key collection without confirming the contract protects you if your BTO completion date shifts (delays happen) — clarify deposit + scheduling terms for that scenario.