Toilet Bowl, Basin and Shower Mixer for an HDB Bathroom: Name the Model Before the Plumbing Days, and Skip the Cheapest Brand

Guide · By Larry Hoo, HDB Licensed Renovation Contractor · 5 Nov 2026

Pictured above: the shower wall in a bathroom from our project archive (140BB). A concealed mixer plate sits on the tiled wall, the spout comes out below it, a hand shower hangs on its hose beside the glass screen, and the floor drain is set into the floor tile. Where each of these sits was fixed inside the wall before a single tile went up.

"Can I just choose the toilet, basin and mixer later, when the tiles are done?" is a question we hear at the bathroom site visit. The honest answer is that the fitting is late but the decision is early. This guide sets out why, what our published pages say about brands, and what to put on the quotation.

It gives no price for any toilet, basin or mixer. We do not publish one, because it depends on the model. The only figures here are the ones already on our bathroom page.

The short answer

Name the model before the plumbing days. On our published bathroom programme the plumbing and electrical re-routing is days 3 to 5. Sanitaryware is installed on days 15 to 17. The choice is needed about two weeks before the fitting.
The mixer and rain shower heights are fixed inside the wall. Our plumbing guide says they are set at first fix and should be decided with the actual fittings in hand. "Standard height" is not a standard across products.
Skip the cheapest brand. Our bathroom page lists "cheap mixer and toilet brands" as a common mistake and recommends mid-range brands, naming the entry lines of Grohe, Roca and Hansgrohe.
A model name on the quotation beats "as per discussion". A line that reads TBC is a future decision, and a late decision costs time.
If you supply your own, you still need the model early. You may not need to have bought it, but the contractor needs the model number and its installation sheet before the pipes move.

Why the fitting is late but the decision is early

A bathroom job runs in a fixed order. On our published bathroom process:

Days 1 to 2: hacking. Days 3 to 5: plumbing and electrical re-routing, with new soil and waste pipe positions, water heater wiring and the exhaust fan rough-in.
Day 6: waterproofing. Days 7 to 8: the 24-hour ponding test.
Days 9 to 14: floor screed, wall and floor tiling, grouting.
Days 15 to 17: sanitaryware, vanity, mirror and accessories. Days 18 to 20: false ceiling, lighting, final fittings, cleaning and handover.

The pipes are laid on days 3 to 5, the wall is closed and tiled after that, and the toilet bowl, basin and mixer are only connected on days 15 to 17. Whatever is connected has to meet the pipe where the pipe already is. If the model is not chosen when the pipes go in, the positions are guessed, and a guess inside a wall is paid for twice: once to open it, and again to make good the waterproofing and the tile.

That is why our plumbing guide says rain shower and mixer heights are fixed at first fix inside the wall, and should be decided with the actual fittings in hand. We make the same point about the water heater in our guide to the instant or storage heater and where it goes before tiling: the heater, the mixer and the shower rail are one layout, not three separate purchases.

What our bathroom page says about brands

Our bathroom page names cheap mixer and toilet brands as a mistake to avoid. It says sanitaryware is one place where saving $200 today costs you $600 in replacement labour three years later, and that we recommend mid-range brands, naming the entry lines of Grohe, Roca and Hansgrohe, over the cheapest options.

Read that as our rule of thumb, not a measured study, and not a promise about any one product. The logic is the one in the sentence: the fitting is the small part of the cost and the labour to replace it is the large part. A cheap mixer that drips behind a tiled wall is not a $200 problem, because the wall has to be opened to reach it.

Three fittings, and what to settle for each

The toilet bowl

Floor-standing or wall-hung. Some of the bathrooms in our project archive, 140BB for one, have wall-hung bowls. A wall-hung bowl is a different installation from a floor-standing one, with the cistern and its support built into the wall behind it. That is a plumbing-days decision, not a fitting-days one.
Where the outlet meets the pipe. The bowl has to line up with the soil pipe. If you are moving the toilet at all, read our guide to what the pipes and floor allow before hacking first.
Ask for the installation sheet. The model's own sheet shows the dimensions your contractor needs to set the pipe.

The basin

It follows the vanity. Our bathroom page lists under-counter and vessel basins with custom vanity cabinets, and the basin tap and waste position depends on which one you pick. Our guide to the vanity and mirror, and the basin pipe position before tiling goes through it.

The shower mixer

Concealed or exposed. A concealed mixer, like the one in the photo above, puts the valve body inside the wall and only the plate and handle outside. It looks cleaner, and it is exactly the part you cannot reach once the wall is tiled. That is the strongest reason to choose a model with parts your contractor can still get in future.
The whole shower set, as one. The mixer, the rain shower head, the hand shower and the floor trap are all positioned at the plumbing stage. Our guide to the shower screen in an HDB bathroom shows how the screen and the mixer constrain each other.
Heights from the actual fitting. Do not set a height from a drawing alone. Ask your contractor to mark it on the wall from the product in hand.

Spare parts: the question nobody asks at the showroom

Anything with an unusual cartridge, an obscure spare part or a long lead time turns a breakage into a void week. We say so in our guide to renovating a flat to rent out, and it applies to an owner-occupier too, because you also need a working shower on the morning after something fails.

So before you fall for a particular mixer, ask two things at the shop or of your contractor: can a replacement cartridge or hose be bought locally, and how long would it take?

If you want to supply the fittings yourself

This is allowed and often sensible for the last items to go in. Our guide to buying your own materials sets out the rule: it works when a late delivery does not hold up a trade and no dimension depends on the item. Sanitaryware fails the second test, because the pipes depend on it. Our single-bathroom guide adds that owner-supplied sanitaryware moves the risk of late, damaged or wrong-size items to you.

So if you are buying the toilet, basin or mixer yourself, send your contractor the model number and the installation sheet before the plumbing days, open and inspect every box on delivery, and photograph the item and its packaging before it is handed over.

What to put on the quotation

Our bathroom quotations itemise the waterproofing, tile cost per square metre, sanitaryware, vanity, accessories and labour separately, so the sanitaryware line is the place to look. We cover reading the other lines in our guide to comparing a bathroom quotation line by line.

Brand and model for the toilet bowl, the basin, the tap and the mixer, not "toilet set" or "mixer, as per discussion".
Whether each is a fixed item or a provisional sum, and what happens to the price if you change the model.
The date by which each choice must be made. Our variation-orders guide puts it this way: a decision made before its date is free.
Who supplies each item, you or the contractor, written against each line.

Questions to put to your contractor

Which model is this line for? Ask for the brand and model, not a category.
By what date do you need my choice? It should be before the plumbing days, and the date should be on paper.
Which fittings change a pipe or wall position? A wall-hung bowl, a concealed mixer and a rain shower do.
Can I see the installation sheet for the model? The sheet carries the dimensions the pipe depends on.
Can the cartridge, hose or other spare parts be bought locally? Ask how long a replacement takes.
If I supply the item, who answers for a chip or a wrong size? Get the answer before you order.
Will I get photos of the pipework before the wall closes? It is the one view you will not get again.

A checklist to take to the site visit

Toilet bowl, basin, tap and mixer chosen by brand and model, written on the quotation.
Choice date set before the plumbing days, which are days 3 to 5 on our programme.
Floor-standing or wall-hung decided, and any wall build-up for a wall-hung bowl agreed.
Concealed or exposed mixer decided, together with the rain shower and hand shower, as one set.
Heights marked on the wall from the actual fitting, not from a drawing.
Spare-part availability asked about, for the cartridge and hose.
Supplier named for each item, with the installation sheet sent early if it is yours.
Photos of the concealed pipework promised before the tile goes up.

Choosing the toilet bowl, basin and shower mixer for your bathroom? WhatsApp us on 9107 2601 with your flat type, your estate and whether it is the common or master bathroom, and we will go through the models and the plumbing positions at a site visit. Any price follows that visit. The full bathroom process is on our bathroom renovation contractors page, and you can see more of this home in our project photos.

Live jobs

Frequently asked questions

When do I have to choose the toilet, basin and mixer?

Before the plumbing days. On our published bathroom programme, plumbing and electrical re-routing is days 3 to 5 and sanitaryware is installed on days 15 to 17, so the choice is needed about two weeks before the fitting. Our plumbing guide says rain shower and mixer heights are fixed at first fix inside the wall.

Which brands do you recommend for a bathroom?

Our bathroom page recommends mid-range brands, naming the entry lines of Grohe, Roca and Hansgrohe, over the cheapest options. It says saving $200 on sanitaryware today can cost $600 in replacement labour three years later. That is our rule of thumb, not a price for any model, and we do not publish prices for named models.

Can I buy my own toilet bowl, basin and mixer?

Yes, but the contractor needs the model number and its installation sheet before the plumbing days, because the pipes depend on it. Owner-supplied sanitaryware also moves the risk of late, damaged or wrong-size items to the owner, so open and inspect every box on delivery and photograph the item and its packaging.

Why does a concealed mixer need an early decision?

The valve body sits inside the wall, so its position and height are fixed when the pipes go in and cannot be changed after tiling without opening the wall. Decide the mixer, rain shower and hand shower as one set, and set heights from the actual fitting.

What should the sanitaryware line on the quotation say?

The brand and model for each item, whether it is a fixed item or a provisional sum, who supplies it, and the date by which the choice must be made. A line that reads "as per discussion" is a decision still waiting to be made.

Larry Hoo — HDB Licensed Renovation Contractor (HB-09-5667H)

Larry Contractors Pte Ltd · 15+ years · 500+ projects · own carpentry factory in Singapore. Read more about Larry →

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