Do You Really Need a Separate Toilet? The Pros and Cons
Almost every family home I walk into in Australia has one, and almost every new plan I’m sent has quietly deleted it. The separate toilet — the little room with a pan, a door, and not much else — has gone from standard to optional to slightly embarrassing in about two decades. And now people ask me about it in a lowered voice, as though wanting one is a bit daggy.
It isn’t. But it also isn’t automatically right. This is one of the few layout decisions where I actually change my answer depending on who’s asking, and I’d rather explain how I decide than hand you a verdict that doesn’t fit your house.
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The short answer, before I talk you around
If more than two people share one bathroom, keep the separate toilet. If it’s you and one other person, or you and a partner with an ensuite already, you almost certainly don’t need it and that floor area is worth more somewhere else.
That’s the rule I use, and it holds up about ninety per cent of the time. The rest of this post is the ten per cent, because that’s where people get it wrong and where the money gets wasted.
What you’re actually buying is capacity, not privacy
People describe the separate toilet as a privacy thing. It isn’t, really — a door is a door. What you’re buying is capacity: the ability for two things to happen at once.
One person on the toilet in a combined bathroom takes the entire room offline. Nobody brushes their teeth, nobody showers, nobody gets a child into the bath. In a house with four people and one bathroom, that single fact shapes every weekday morning. It’s the reason the separate toilet became standard in Australian family homes in the first place, and it’s a better reason than nostalgia.
The second thing you’re buying is guest comfort. A visitor who needs the toilet in a combined bathroom is walking past your shampoo, your damp towels and whatever is on the vanity. A separate toilet with a small hand basin lets you keep the rest of the house’s mess to yourself. If you entertain even occasionally, that’s worth more than it sounds.
And the third — the one nobody lists — is smell and steam separation. A toilet in its own compartment with its own exhaust is a different daily experience from a toilet sitting a metre from a hot shower. Two fans doing one job each beats one fan doing two.
The 1.2 metre rule that explains why yours feels wrong
Here’s the bit that catches people out, and it’s the reason so many separate toilets feel like a cupboard with a bad attitude.
Under the National Construction Code, a fully enclosed toilet compartment has to do one of two things: either the door opens outwards, slides, or can be readily removed from outside, or there’s a clear space of at least 1.2 metres between the pan and the doorway. It’s a safety provision — if someone collapses in there, you have to be able to get to them.
In practice, almost nobody has 1.2 metres of clear floor in front of the pan. So the door swings out. And an outward-swinging door in a hallway is the single most common reason a separate toilet annoys everyone who lives with it — it blocks the corridor, it clashes with the bathroom door opposite, and someone eventually gets hit by it.
The fix is almost always a cavity slider. It costs a bit more, it needs a stud wall with nothing in it, and it removes the problem permanently. If you’re building or moving a wall anyway, decide this at frame stage — retrofitting a cavity slider into a finished wall is a miserable job.
On size: I plan separate toilets at around 900 × 1500mm as a comfortable minimum. You can go smaller and it will still comply, but you’ll feel your knees against the door every time, and a room you resent using isn’t worth the walls it took to build.
What it costs you — and I don’t just mean money
A separate toilet is not free floor area. At 900 × 1500mm you’ve committed about 1.35 square metres, plus the wall thicknesses either side, plus a door and its swing. In a small home that is a linen cupboard, or the difference between a 900mm shower and a 1200mm one, or the walk-in robe you actually wanted.
It’s also a second wet area. Second exhaust fan, second light, second lot of waterproofing at the pan, second door hardware. None of it is expensive on its own and all of it adds up — and if the toilet sits away from the existing stack, you’re paying to run waste pipe to it as well. Moving a toilet is the most expensive plumbing change in a bathroom, comfortably ahead of moving a basin or a shower.
The less obvious cost is what it does to the room next door. Carving a separate toilet out of a bathroom leaves the bathroom narrower, and narrow bathrooms are where bad layouts come from. I’d far rather have one well-proportioned bathroom with a proper vanity run than a cramped bathroom and a cramped toilet sharing the same footprint. Splitting a small room in two doesn’t create two rooms. It creates two problems.
The households where I’d fight to keep it
Three or more people sharing one bathroom. Non-negotiable. This is the whole argument and it doesn’t need a second one.
A family with school-aged kids. Mornings are a scheduling problem, not a design problem, and the separate toilet is the cheapest scheduling fix available.
Anyone with no powder room and a living area guests actually sit in. If your only toilet is inside the family bathroom at the end of a bedroom corridor, every guest walks through the private half of your house. A separate toilet near the living zone solves that for a fraction of what a full powder room costs.
Anyone planning to stay put for twenty years. Households change. Kids arrive, parents move in, someone works from home. Capacity you don’t need today is capacity you’ll be glad of later, and you can’t add a toilet room to a finished house cheaply.
Multi-generational homes. Obvious once you say it, routinely forgotten at plan stage. If an older parent is going to live with you, a toilet they can reach without crossing the house matters enormously.
The households where I’d take the wall out
Two adults with an ensuite. You already have two toilets. A third in its own room, in an apartment or a small house, is floor area doing nothing. Take the wall out, give the bathroom a decent vanity, and stop apologising for it.
Anyone whose separate toilet is so small it’s unusable. Plenty of 1970s and 80s homes have a toilet room that’s about 800mm wide with a door that opens into your shins. That room isn’t giving you capacity, it’s giving you a bad twenty seconds twice a day. Absorbing it into the bathroom usually buys a proper double vanity or a bath you can actually get into.
Anyone chasing a bath. If a freestanding bath is the thing you’ll love about your bathroom, and the only way to fit it is to absorb the toilet room, do it. I’d rather you use the room daily than preserve a layout on principle.
Single-occupant homes, always. There is nobody to queue behind you.
One caveat before you swing the sledgehammer: removing a separate toilet from a three or four bedroom family home does slightly narrow your buyer pool when you sell. Not fatally, and not enough to keep a room you hate — but if you’re renovating with resale in mind rather than your own comfort, weigh it.
The option most people should be looking at instead
The debate is usually framed as separate toilet versus combined bathroom, and that framing hides the answer.
The three-way bathroom — vanity in one compartment, shower and bath in another, toilet in a third, all under one roof — is the highest-functioning family layout there is, and it’s criminally underrated. Three people, three tasks, no negotiation. The vanity compartment can open to the hallway and double as a general hand-washing station, which takes a surprising amount of pressure off the room.
It costs more in walls and doors than one open room. It repays that every single morning for the life of the house. The catch is that each compartment needs its own light and ventilation plan — the internal compartments can’t borrow the window — so it’s a layout you have to design properly rather than draw and hope.
If you have the width for it, this is the version of “separate toilet” I’d push you toward. It gets you the capacity without stranding a toilet on its own out in the hallway.
A project where the toilet was the actual problem
On a project I called Fourty-one, the ensuite had a layout that was all over the place. The toilet sat right at the door — the first thing you saw walking in. There was a large window cutting straight through the middle of where all the utilities needed to go, and the shower was jammed into a corner, hard to get to and dark.
The instinct with a room like that is to make it bigger. We did the opposite. We made the ensuite smaller on purpose and gave the space back to the walk-in robe, which the client actually needed. The result was a smaller room with a layout that finally made sense.
I bring it up here because it’s the same decision in reverse. The question was never “how much room does the toilet get” — it was “where does this toilet belong, and what is the space around it doing for us”. Most bathroom problems I’m sent are that question wearing a different hat.
Keeping it? Then make it earn the room
If the separate toilet is staying, a handful of things turn it from a compliance box into a room people don’t mind being in.
Put a hand basin in it if the plumbing allows. This is the single biggest upgrade. Hands get washed where they need to be washed, and the room stops depending on the bathroom next door. A wall-hung basin at around 300mm deep is plenty — you’re washing hands, not filling a bucket — and it keeps the floor visually open, which matters enormously in a room that small. The Blue Space is where I send people for compact wall-hung basins and slimline toilet suites; anyone shopping through my link gets a discount, and the amount varies by product, so it’s worth going through the link rather than straight to their site.
Give it a real exhaust fan. A toilet room with no window and no fan is how these rooms got their reputation. This is not the place to save eighty dollars.
Sort the door properly. Cavity slider if the wall allows it, outward swing if it doesn’t, and check what the door hits when it’s open before you commit. Draw the swing on the plan. Everyone forgets to draw the swing.
Let it be the bold room. A separate toilet is small, briefly occupied and visually self-contained, which makes it the safest place in the house to do something you’d never commit to across a whole bathroom. On one of my projects we tiled every wall of the powder room in Japanese mosaic, and that single idea is the entire room. Deep colour, a patterned tile, a dark ceiling — it’s a small dose and everyone’s only in there for a minute.
Don’t forget storage. A shallow niche or a narrow cabinet above the cistern holds the spare rolls and stops the floor becoming a staging area. Two minutes of planning, permanently better room.
If a bathroom renovation is on the cards rather than happening this month, it’s worth saving that link somewhere — the discount comes through the link itself, there’s no code to type in, and bathroom decisions tend to take a while.
My rule of thumb
Count the people, not the bedrooms. A four-bedroom house with two occupants doesn’t need a separate toilet. A two-bedroom house with four occupants desperately does.
Then ask what the space would do instead. If the honest answer is “a slightly bigger bathroom that I’d use the same way”, keep the toilet. If the answer is “the linen cupboard this house has never had” or “a shower I can turn around in”, take it out. The separate toilet isn’t sacred and it isn’t outdated. It’s a capacity decision, and capacity decisions are answered by counting.
And if you’re staring at a plan and can’t tell which side of that line you’re on, that’s precisely the kind of thing a fresh set of eyes sorts out in an afternoon. Fix My Floor Plan is $297 a room and exists for this — you send the plan and the problem, I send back a layout that works. If the whole bathroom is up for grabs and you’d rather talk it through, a design consultation is ninety minutes of straight answers, online, wherever you are.
Still not sure what’s right for your own place?
That’s the part I do — and there are two ways in, depending on how much you need sorted.
Fix My Floor Plan — $297 a room. Send me your floor plan and a few photos. I’ll tell you what I’d change: where the furniture goes, what’s making the room feel awkward, and the practical next steps to fix it. Back with you in 5–7 business days, and there’s not a single meeting involved.
Or a Design Consultation — $550. Ninety minutes on your whole space: layout, colours, materials, joinery, storage, or just a second opinion before you commit to something expensive. Online, wherever you are in the world.
