Bathroom Renovation: Costs & Waterproofing Explained (2026)

The bathroom is small, but it is the room where cutting the wrong corner costs you the most. Get the waterproofing wrong and you are not just retiling – you could be paying to repair the ceiling of the flat below yours. This guide explains what a bathroom renovation actually costs in Singapore, why waterproofing sits at the centre of the whole job, and how to plan the work so it lasts.

Overlay vs hack-and-replace

There are two broad ways to renovate a bathroom. An overlay lays new tiles on top of the existing ones. It is cheaper, faster and less messy, but it has one big limitation: it does not touch the waterproofing underneath. A hack-and-replace strips everything down to the screed, lets you lay a fresh waterproofing membrane, and then retiles. It costs more and takes longer, but it is the only way to renew the waterproofing.

The right choice depends on the state of your bathroom. If the existing waterproofing is sound and you just want a fresh look, an overlay can make sense. If your bathroom is old, leaking, or you are doing a full renovation anyway, hacking down and redoing the waterproofing properly is the safer long-term decision. Note that both hacking and tiling over existing tiles in an HDB flat require a permit and a registered contractor.

Why waterproofing is the most important step

Waterproofing is a membrane applied to the floor and lower walls before tiles go on. In a wet area, it is the layer that stops water from soaking through the screed into the structure below. It is invisible once tiled over, which is exactly why it gets skimped on – and why that is a costly mistake.

Here is the part every HDB owner needs to understand: if water leaks from your bathroom into the unit below, HDB generally holds you, the upper-floor owner, responsible for the repair. That can mean paying to fix a neighbour’s ceiling and redoing your own floor. Proper waterproofing before tiling, with adequate curing and a water-ponding test, is your protection against that scenario. Never let a contractor rush or skip it to save a day.

Tiling and screed

After waterproofing, the floor is screeded to the right gradient so water drains toward the floor trap, and then tiled. Tile choice affects both cost and safety: for wet floors, matte or textured anti-slip tiles are far more sensible than glossy ones. Wall tiles have more freedom in finish. Larger-format tiles look sleek but need a flatter substrate and careful laying, which can raise labour cost.

The gradient matters as much as the tile. Poor fall leaves water pooling, which over time stresses the waterproofing and grout. A competent tiler builds the correct slope into the screed – another reason to use experienced, registered trades.

Grout choice is a small detail that pays off. In wet areas, grout takes daily moisture and can discolour or grow mould over time. A quality grout, and good sealing where needed, keeps the finish looking clean for longer and reduces the chance of water working its way into the joints. It is a modest cost that spares you regrouting a few years down the line.

Sanitary ware, taps and the shower

Sanitary ware is a separate budget line: the WC (toilet bowl), wash basin, and the shower system. Prices range widely, from basic reliable fittings to premium suites. A rainfall shower head, a concealed cistern, or a wall-hung WC all cost more, both for the item and because they need more involved plumbing behind the wall.

Spend where you touch daily – a decent mixer tap and a comfortable shower – and be sensible about the showpiece extras. For standalone fitting and plumbing prices when you are not doing a full renovation, our guide to electrician, plumber and handyman costs in Singapore is a useful reference.

Think about accessories at the same time as the sanitary ware, because towel bars, robe hooks, a mirror cabinet and a shower shelf all need fixing points that are easier to plan before tiling than to retrofit after. Small storage decisions make a small bathroom feel far more usable, and a mirror cabinet often does more for daily life than an expensive designer tap. Decide what you actually reach for each morning, and build the layout around that rather than around a showroom display.

Water heaters and the false ceiling

Your water heater choice affects both the electrical work and where pipes and units sit. Instant heaters are compact and heat on demand; storage heaters hold a tank of hot water and suit households with higher simultaneous demand. The decision changes your plumbing, wiring and space planning, so make it early – our guide on instant vs storage water heaters in Singapore lays out the trade-offs.

Many renovations add a false ceiling in the bathroom to conceal exposed pipes and ducting and to house downlights and an exhaust fan. It tidies up the look and gives you access to concealed pipework, but it is an added cost and lowers the ceiling slightly. In older flats with visible service pipes, it is often worth it.

Rough cost ranges for 2026

Treat the table below as an approximate 2026 guide only. Actual cost depends on overlay versus hacking, tile and sanitary ware choice, whether you add a false ceiling, and your contractor. Always verify current quotes.

Scope	What it includes	Rough cost per bathroom
Overlay refresh	New tiles over old, new sanitary ware, no new waterproofing	Lower – a few thousand and up
Hack-and-replace	Full hack, new waterproofing, retiling, sanitary ware	Mid range, higher per bathroom
Premium	As above plus false ceiling, feature tiles, premium fittings	Upper range

Bathrooms are one slice of a whole-home budget. To see how they compare across the full renovation, read our overview of renovation cost by flat type in Singapore.

Warranty and timeline

Ask for the waterproofing warranty in writing and understand what it covers and for how long – it is common for waterproofing to carry a multi-year warranty, but the exact terms vary by contractor, so confirm rather than assume. Keep the paperwork; if a leak develops, it is your evidence.

On timing, a hack-and-replace bathroom typically runs around one to two weeks per bathroom, because waterproofing needs time to cure and be tested before tiling can begin. Rushing this stage is where problems start. If you have two bathrooms, plan whether they run in sequence or parallel, since it affects both cost and how long you are without a working toilet. For how bathrooms fit into the wider schedule, see our HDB renovation timeline.

The bottom line

Your bathroom renovation cost is shaped by one key fork – overlay or hack-and-replace – and by your sanitary ware and finishes. But the decision that matters most for your wallet in the long run is waterproofing. Because HDB holds you responsible for leaks to the flat below, a properly laid, cured and tested membrane is not the place to economise. Use HDB-registered contractors, secure the correct permits for hacking and wet works, get the waterproofing warranty in writing, and treat every figure here as rough 2026 guidance to verify against current quotes. When you are ready, get matched with vetted renovation contractors below.

Related guides: Bathroom Fittings