What HDB Sellers Must Disclose in 2026: Unauthorised Renovations, Leaks and the 8-Week Fix Window

Expert takeaway: HDB resale is a buyer-beware deal, but that does not let sellers off: any unauthorised renovation must be rectified before completion, which lands about 8 weeks after HDB accepts the resale application. Sellers who find and fix problems before listing protect both their timeline and their asking price.

Most HDB sellers worry about the price. Fewer think about what is behind the feature wall, under the hacked kitchen floor or above the stained bathroom ceiling. In 2026, what HDB sellers must disclose comes down to one practical point: HDB checks for unauthorised works before completion, buyers check for everything else, and anything either side finds late becomes a bargaining chip against you. This guide sets out the official rules, the timeline and the fixes worth making before your flat goes on the market.

What HDB Sellers Must Disclose: The Official Rules on Renovations

The official answer is that the seller must rectify all unauthorised alterations and additions in the flat before resale completion, while the buyer carries the duty to verify that renovation works are authorised. HDB's resale procedures state that the purchase is on a caveat emptor basis, and that the buyer is responsible for any irregularity discovered after purchase, including unauthorised renovation works done by the seller.

That split looks like it favours sellers. In practice it does not, for three reasons drawn from HDB's resale rules:

• Completion is conditional. Sale completion requires the seller to rectify all unauthorised alterations or additions. A seller cannot hand over a flat with unapproved works and walk away.
• HDB inspects. An HDB Branch inspection checks for unauthorised renovation works that may damage HDB property and affect the structural stability of the flat or building.
• HDB has legal powers. Under the Housing and Development (Renovation Control) Rules, HDB can require an owner who carried out unauthorised works to remove them and reinstate the flat to its prior condition, or carry out specified repairs. Where HDB allows unauthorised work to be retained, the owner pays an administrative fee; check the current amount with HDB.

Equally important is what the inspection does not do. HDB states that the resale inspection does not ascertain the value of the flat, the condition or safety of renovation works, or compliance with legislation on fittings and fixtures such as window legislation. A seller should not read a clean HDB inspection as a certificate that the flat has no defects, and a buyer will not either.

Leaks and defects HDB does not inspect

Leaks, ceiling stains, cracked tiles and faulty fittings fall outside HDB's unauthorised-works check, so the buyer's own viewing and inspection is where they surface. Because the sale is caveat emptor, the rules put the onus on the buyer to look. But a buyer who spots water damage after the Option to Purchase is granted has 21 calendar days, ending at 4pm on the 21st day, to decide whether to exercise, and that is ample time to come back asking for a lower price. Answer buyer questions truthfully and in writing; whether a specific statement creates legal liability is a question for your lawyer, and our guide to what a conveyancing lawyer does in a resale explains where that advice fits.

The HDB Resale Timeline Leaves About 8 Weeks to Fix Problems

Completion takes place about 8 weeks after HDB accepts a complete resale application, according to HDB's resale process, and HDB will not bring the completion date forward. Any unauthorised works must be rectified inside that window, which is why the cheapest time to deal with them is before you list.

Worked timeline: a 4-room sale in late 2026

Take a seller whose complete resale application HDB accepts on 2 November 2026. On the approximate durations above, the documents to endorse would be ready around 23 November and completion would fall around 28 December 2026. If the seller only learns in mid-November that an extended kitchen counter or a removed wall needs reinstatement, they have roughly six weeks to engage a contractor and finish the work, over the year-end period. Moving completion later is possible only with every buyer and seller signing a written request within a week of HDB's acceptance letter. If you are also buying your next home, our guide to negotiating an extension of stay shows how fragile these dates become.

There is a second trap. HDB's rules state that no renovation works shall be carried out to the flat pending resale completion, and if they are, seller and buyer are jointly and severally liable for any resulting damage and must rectify it to HDB's satisfaction. Agreeing to let a buyer's contractor start early, or doing a cosmetic refresh yourself mid-sale, exposes you to liability you did not need.

Fixes That Protect Your HDB Sale Price

The fixes that protect your price are the ones a buyer would otherwise use as leverage: unauthorised works HDB will make you reverse anyway, and visible water damage that invites a low offer. Sort issues into three groups before you list.

Practical steps, in order:

• Gather renovation records. Find the approvals and contractor paperwork from your own renovation, and any you received from the previous owner. Gaps tell you where to look harder.
• Walk the flat as a buyer would. Check bathroom ceilings, the area under sinks, window frames and any hacked or extended areas.
• Fix before listing, not after the OTP. Completing works before the Intent to Sell avoids the ban on renovations pending completion and keeps the 8-week window clear.
• Disclose what you fixed. A short written record of repairs reassures buyers and narrows the room for renegotiation.

Before you price the flat, check what your flat is likely to fetch so you can weigh repair costs against the price you expect. For context, the PropertyNet 2026 price table puts HDB resale 4-room flats at $550,000 to $850,000 and 5-room or executive flats at $700,000 to $1.2M (verified Sep 2026). On a $650,000 4-room, a buyer who finds a leak during the OTP risks only the $1 to $1,000 option fee by walking away. That is a weak lock-in for the seller.

Opportunities and Risks for HDB Sellers

The opportunity is that a seller who resolves renovation and leak issues upfront can hold firm on price, while the risk is that late discoveries cost time, money and negotiating position.

Opportunities:

• A documented, defect-free flat stands out to buyers who already hold an HFE letter and want certainty.
• Clearing works early leaves the about-8-week completion period for moving out, not for contractors.
• Your cash proceeds arrive in your bank account by the next working day after completion, and HDB refunds your CPF within 7 to 14 working days of the appointment, so a smooth completion keeps your next purchase on schedule.

Risks:

• HDB can require removal and reinstatement of unauthorised works, which may cost more than the original renovation.
• Works carried out pending completion make seller and buyer jointly and severally liable for damage.
• A buyer can walk away during the 21-day OTP. If you must sell within 6 months to get an ABSD refund on a second home, your flat counts as sold only when the buyer exercises.
• You can only sell on the open market after the minimum occupation period: 5 years for Standard flats, 10 years for Plus and Prime flats, 20 years for Fresh Start flats. Confirm your position on HDB's eligibility page for selling a flat.

Repairs also come out of the same pot as your CPF refund. On sale you refund the CPF principal used plus accrued interest at the 2.5% Ordinary Account rate, going to your OA if you are under 55 and first topping up your Retirement Account to the required retirement sum from 55, as set out in CPF's home ownership rules. Work out your own CPF refund and cash proceeds before budgeting for works, and see our breakdown of HDB sale proceeds, costs and cash. If your next move is a private home, browse our new launch condo reviews once your sale timeline is clear.

Every flat has its own renovation history, and the right call between fixing, disclosing and repricing depends on your timeline and your next purchase. If you would like an independent view of your flat's value, the works worth doing before you list and how your sale dates fit your next move, reach out to PropertyNet.SG for personalised advice.