Every project includes one
Interior
Report.
Photoreal 3D, every working drawing, and live milestone tracking — agreed before any work begins, so the price can't creep, the design can't drift, and you're never renovating on trust alone.
= every detail matters
Accredited & protected
Renovation is one of Singapore's most complained-about industries — the reason CaseTrust exists. This is what protects you here:
CaseTrust Accredited
Standard contract · deposit protected · dispute resolution
bizSafe Level 3
Workplace safety & health management certified
The Interior Report
Every detail, drawn before we build.
Photoreal 3D of your finished home, plus the full set of working drawings that builds it — every material, dimension and fitting decided up front, so nothing is improvised on site. Improvisation is where budgets blow and disputes begin — we remove it before the first tile is laid.
Photoreal 3D — the finished home, before we build.
Built from real drawings
More than a mood board — the concept, fully drawn.
01Proposed layout — every wall, door and built-in, dimensioned to the millimetre.
Real project · client details redacted
Start to finish
See every stage as it happens — not just the finished home.
Vanishing contractors, surprise costs, a final bill that outgrew its quote — every renovation risk lives in the gap between what was promised and what was written down. We close that gap in writing, three times:
From first sketch to handover:
Report — aligned
Photoreal 3D and the full drawing set land first. You approve the home on paper — while changing your mind still costs nothing.
Build — tracked
Every milestone, site photo and payment, live in your private portal. You see what we see — no radio silence, no surprise bills.
Handover — checked
We snag every defect with you, then hand over the home that matches the report — not one that's “close enough”. Settle by PayNow.
During the build, you're never guessing:
- Design & quotationdone
- Hacking & masonrydone
- Carpentry installationin progress
- Defect check & handoverupcoming
The team
The names on your drawings are the people who build your home.
Founder
Benjamin Mah
Leads the studio's vision — a meticulous eye for detail and an uncompromising standard for every space.
Co-Founder
Ken Wong
Bridges design and execution — an architectural mind with a feel for structure and proportion.
Instant estimate
See what your home should cost.
Your estimate
HDB 4-room · bto / new · standard reno
$36,000–$50,000
Free and itemised · no obligation
Ranges are benchmarked against published 2026 Singapore renovation cost guides — MoneySmart, Qanvast, Design Authority — and calibrated from our own completed projects. They're an honest ballpark, not a fixed quote — your itemised quote stays close to this range.
Selected work
Homes we've solved
Homeowners
What they say after moving in.
Common questions
Answers before you ask.
How long does a renovation take?
A normal renovation takes about 8 to 10 weeks, depending on the scope of work — a cosmetic refresh is faster than a full hack-and-rebuild. You can follow every milestone, site photo and payment live in your private project portal.
Do you handle both HDB flats and condominiums?
Yes. The Interior Formula designs and renovates HDB flats (BTO and resale) as well as private condominiums and apartments across Singapore.
Is your pricing transparent?
Every quotation is fully itemised line by line with no hidden costs, and our quotes are not subject to GST. You get a free, exact quote after a short consultation — and our instant estimator shows an honest range upfront.
What is the Interior Report?
Every project includes an Interior Report: photoreal 3D renders, the complete set of working drawings, and live milestone tracking — one source of truth agreed from the first concept through to handover.
How much does it cost to renovate an HDB flat in Singapore?
As a guide, a standard renovation for a 4-room HDB BTO starts from around S$36,000; 5-room and Executive flats cost more, and resale flats more again because of hacking and rectification work. A new-launch condominium fit-out typically runs S$30,000–60,000. Use the free instant estimator on our homepage for a range tailored to your home, then get an exact itemised quote after a short consultation.
Is the quote and consultation really free?
Yes. The consultation and the full itemised quote are free, with no obligation to build. You only commit once you've reviewed and signed the quotation.
Is The Interior Formula accredited?
Yes — The Interior Formula is CaseTrust accredited and bizSafe Level 3 certified, and serves homes across Singapore from our studio at APEX@Henderson.
How do I avoid hidden costs and renovation disputes?
Insist on a fully itemised quotation before work starts, a CaseTrust standard contract with deposit protection, and a written record of every change. That is how The Interior Formula runs every project by default — each line item priced upfront, every milestone and payment tracked in your private portal, and defects snagged together before handover.
Start here
See your home before you commit a cent.
Free, itemised, no obligation to build — or browse a real sample report first.