HDB resale renovation timeline: what to expect, week by week

An HDB resale renovation in Singapore takes 6 to 10 weeks for a 4-room flat, longer for bigger units. This is what actually happens week by week, why some phases are louder than others, and how to plan the move so you're not caught between an ending lease and a half-built bathroom.

The fast version: design and permits take 2-3 weeks in parallel with anything else. The build itself runs roughly 4-7 weeks depending on flat size. Plus a week for snag and handover.

The headline timeline

Based on what most of our resale projects end up running:

• 3-room resale (around 65 m²): 6-8 weeks total
• 4-room resale (around 90 m²): 7-9 weeks — the most common bracket
• 5-room resale (around 110 m²): 8-10 weeks
• Executive (around 140 m²): 9-12 weeks

These assume nothing unusual comes up. We'll cover the common reasons projects run longer further down.

Weeks 1-3: design and permits

This phase runs in parallel — design work happens in your home while permit applications are with HDB. There's no construction work yet, so you can still be living in the old place or visiting prospective fittings shops.

What we do during these weeks:

• Site visit and full measurement of the existing flat
• Floor plan with the new layout drawn up
• Hacking layout submitted to HDB for permit (typically 2-3 weeks processing)
• Electrical single-line drawing for ME05 L1 sign-off
• Material selection — tiles, fittings, paint colours, carpentry finishes
• Final quote sign-off after you've seen physical samples

The permit step is the rate-limiter. HDB takes 2-3 weeks to review and approve hacking applications. There's no way to speed this up — but you can use this time productively to finalise material choices, which means no time is lost when the permit clears.

Permit cost is $50-$200 depending on scope, passed through to you at cost.

Weeks 4-5: the hack phase

This is the loud, dusty, dramatic part. Walls come down. Old tiles come up. Kitchen and bathroom fittings get ripped out. Built-in wardrobes from the previous owner end up in a skip. Ceiling boards come down. By the end of these two weeks, the flat is a bare concrete shell.

What gets hacked:

• Existing built-ins (wardrobes, kitchen cabinets, TV consoles)
• Old wall and floor tiles in wet zones
• Ceiling boards if they're being replaced
• Partition walls being removed per the new layout
• Old kitchen and bathroom fittings completely stripped

Hours and noise are regulated. HDB allows noisy works between 9am and 5pm on weekdays and Saturdays only — no Sundays or public holidays. We notify your neighbours on the floor above and below before we start, which usually keeps complaint levels to one or two across the whole project (we deal with the Town Council directly if anyone escalates).

Important: you cannot live in the flat during the hack phase. Most clients are in the old place or with family. Some rent a short-term stay for these two weeks.

Weeks 6-7: rough-in (the quiet phase)

Once the flat is stripped, the slower technical work starts. This is where the underlying systems get rebuilt before finishes go on. It's much quieter than hack phase — most days it's 2-3 technicians on site doing precise work.

What happens during rough-in:

Electrical. The old distribution board gets replaced with a modern one — 60A or 100A main, with ELCB (earth-leakage) protection on every sub-circuit. Kitchen, aircon, water heater, and general circuits each get their own breakers so they don't trip when running together. New wiring runs through the entire flat — power points, lighting points, aircon points, all to current Singapore code (BS 7671 / SS 638).

Why this matters: HDB units built before 2000 typically have 5-amp main circuits that simply cannot run modern appliance loads. Aircon + induction hob + water heater going simultaneously will trip the old board. Rewiring is non-optional in most resale renovations and adds significantly to the cost vs a BTO — but it's also what makes the flat actually usable for modern life.

Plumbing. Old pipes either get replaced outright (especially if galvanised or showing corrosion) or rerouted to suit the new layout. We typically use copper or PPR. New shut-off valves are installed at the water heater, kitchen sink, and behind every bathroom fitting, so any future repair can isolate locally without shutting off the whole unit.

Waterproofing. This is critical for resale units. Old bathroom membranes leak — by 20-30 years of age, most are compromised, which is why old HDB units often have water seepage into the unit below. We hack down to the structural concrete slab, apply a two-layer cement-based waterproof membrane, then screed and tile on top.

Weeks 8-9: finishing

Now it starts looking like a home again. The visible work all happens in these two weeks.

Tiling comes first — walls and floors in wet areas, plus any feature walls in living spaces. Carpentry follows: kitchen cabinets, wardrobes, TV consoles, shoe cabinets, study tables. Built-in carpentry takes 7-10 days depending on scope. Painting happens after carpentry (so paint can cover any small touch-ups from install), with two coats throughout the unit.

Aircon installation usually happens late in this phase, after ceilings are finalised and walls are painted. We coordinate with the aircon installer — the renovation quote covers the casing and piping work; the units themselves are typically bought separately.

Week 10: snag and handover

Once everything physical is done, the final week is for snag identification and small fixes. We walk through the flat with you, you flag anything that's not quite right, and we address everything within the week.

Common snag items: paint touch-ups, a wardrobe door that needs an adjustment, grout lines being cleaned up, a power point that's positioned slightly off. None of these are structural — they're the kind of things you only notice once everything else is in.

After snag is closed, the 12-month workmanship warranty kicks in.

What can extend the timeline

The 6-10 week ranges above assume nothing unusual. Things that can add weeks:

Asbestos in old vinyl tiles or ceiling boards.Units built between roughly 1970-85 occasionally have asbestos in old materials. HDB stopped using it by the late 80s. If we spot visual signs, we send a sample to an SAC-accredited lab — if positive, we engage a licensed asbestos removal contractor. Adds 1-2 weeks and $2,000-$5,000 to the project. Non-optional for safety.

Customer-supplied materials with long delivery.Tiles from Taobao, designer fittings from overseas, custom carpentry from a specific brand — anything that takes weeks to arrive can hold up the phase that needs it. We can install customer-supplied items at install-only rates, but factor in 1-2 extra weeks of buffer for delivery coordination.

Scope changes mid-project. "Actually, can we move the kitchen island a metre to the left?" — yes, but electrical and plumbing rough-in may already be done, and redoing them adds a week. We're happy to accommodate changes; just understand they have a knock-on cost.

Permit delays. Sometimes HDB takes 4 weeks instead of 2-3. We can't hack until the permit clears, so this directly extends the project.

How to plan the move

The most stressful part of resale renovation in Singapore is often the move logistics — you're selling your old place, the buyer wants completion on a fixed date, and your new place is being renovated.

A few practical tips:

Start design and permits before key collection.You can't physically start the build until you collect keys, but design and permit application can begin once your completion date is set. This shaves 2-3 weeks off the timeline between key collection and move-in.

Build in a buffer week between renovation end and your move-in date. Things sometimes overrun by a few days. Booking the movers for the week after the planned handover, rather than the day after, saves a lot of stress.

Negotiate the completion date with your buyer if possible. If your old place sale completion is just a week after your new place key collection, you'll be homeless mid-renovation. If you can negotiate 3-4 months between completion of old and key collection of new, you'll have time for the build with much less stress.

Why resale renovation costs more than BTO

Briefly, because three things have to happen in resale that don't in BTO:

1. Hacking and disposal — strip-out alone runs $4,000-$8,000 for a 4-room
2. Full rewiring and DB box upgrade — old electrical systems can't handle modern loads
3. Bathroom and kitchen waterproofing — old membranes are compromised and must be redone from the slab up

Net effect: a resale renovation typically costs 30-50% more than a BTO of the same flat size. A 4-room BTO at $40,000-$55,000 compares to a 4-room resale at $50,000-$80,000.

The short version

For an HDB resale renovation in Singapore, plan for:

• Weeks 1-3: design + permits (you can be elsewhere)
• Weeks 4-5: hack phase (loud, dusty, no living in it)
• Weeks 6-7: rough-in — electrical, plumbing, waterproofing (quieter)
• Weeks 8-9: tiling, carpentry, paint, aircon coordination
• Week 10: snag and handover

Bigger flats add 1-3 weeks at the rebuild end. Asbestos, scope changes, or delayed customer-supplied materials can add more. Start design and permit work before key collection if you can — it's the easiest way to shave time off the total.