By Winfred Quek, Associate Marketing Consultant · CEA R073319H · Crestbrick Pte Ltd (L3010886H) · Published 13 July 2026
Individual unit configurations vary and should be verified against HDB's records for the specific flat. Sources are listed below.
Every so often a resale listing shows a floor area that looks like a typo for the flat type stated. It is not a typo. It is a jumbo flat, a relic of an HDB scheme from decades ago that combined two adjoining flats into one, and it is one of the few genuinely scarce categories of public housing left on the resale market. As an investor minded advisor, I get asked about these often enough that they deserve a proper explainer, separate from the general resale buying guides.
What a jumbo flat actually is
A jumbo flat is the product of an HDB scheme, mainly active in the 1980s and into the early 1990s in a handful of older estates, that allowed two adjoining flats, most commonly two 3 room units, to be combined into a single larger home. HDB physically merged the units by knocking through the shared wall, and the resulting flat was registered as a single unit with a substantially larger floor area than any standard flat type offered at the time.
This is distinct from a modern renovation combining two flats you happen to buy separately today. A jumbo flat was created and registered as one unit by HDB itself, decades ago, and it carries that history in its records, its layout, and often in its remaining lease.
Why the scheme stopped and where jumbo flats still exist
HDB does not offer a scheme to create new jumbo flats today. The flats that exist are concentrated in specific older estates where the combination scheme was offered, and they show up occasionally on the resale market rather than through any current BTO or Sale of Balance Flats channel. Because no new supply is being created, the existing stock of jumbo flats is fixed and, if anything, shrinking as older blocks are eventually redeveloped or their leases run down.
Scarcity also makes valuation harder. There simply are not many comparable transactions to benchmark a jumbo flat against, which makes pricing one, whether you are buying or selling, more art than science compared to a standard flat type with dozens of recent comparable resale transactions in the same block or estate.
The space premium: why jumbo flats sell for more
The premium a jumbo flat commands over a standard flat in the same estate is a straightforward function of floor area. Combining two 3 room flats produces a home meaningfully larger than even a standard 5 room or executive flat of the same era, at a scale that would otherwise require moving to landed housing or a much pricier private unit. For a multi generational family, or a buyer who wants space without leaving the HDB system, that scarcity is genuinely valuable, and buyers have historically been willing to pay for it.
What the premium is not is a guarantee of proportionally faster appreciation. A jumbo flat's value still tracks the same underlying drivers as any HDB flat, location, lease remaining, and estate desirability, layered on top of the size premium rather than replacing those fundamentals. I set out the broader mechanics of what actually moves resale prices in my HDB resale pricing guide, and the same logic applies here, just with a larger unit attached.
The practical realities: utilities, layout and renovation history
Because a jumbo flat began life as two separate flats, some units retain artefacts of that original layout. It is not unusual to find two kitchens, two sets of toilets, or in some cases separate utility meters that were never consolidated into one account after the combination. Whether this is the case for a specific unit depends entirely on how the combination was carried out and whether a previous owner renovated to unify the space.
Renovation history matters more here than in a standard flat, because the quality of how the original wall was knocked through, and whether structural work was done properly and approved by HDB at the time, affects both livability and future renovation flexibility. Ask for any available renovation permits or records from the combination, and e spirit as the checks I recommend in my defects inspection checklist, adapted for an HDB context.
Financing a jumbo flat: lease decay and loan quantum
Jumbo flats were created from flats built decades ago, which means their remaining lease is shorter than a newer flat of comparable size elsewhere in Singapore. That shorter remaining lease affects both HDB loan eligibility and bank loan quantum in the same way it would for any older resale flat: the lease needs to cover the youngest buyer to a certain age for full CPF usage and loan quantum, and the loan amount a bank is willing to extend shrinks as remaining lease falls. Work through the lease decay mechanics in my lease decay impact guide before assuming your financing will stretch as far as the flat's impressive size might suggest.