Toilet Buying Guide Australia: S-Trap vs P-Trap, Set-Out & Toilet Styles

Most wrong toilet purchases happen for one reason: people pick the style first and the plumbing second. Flip it. The right toilet is not just the one that looks good. It is the one that suits your trap type, set-out, inlet position and bathroom layout before anything else.

This Australian toilet buying guide walks through the order that actually works: confirm the trap type, measure the set-out, choose the toilet style, then look at seats, cleaning features and comfort upgrades. Once you know what your bathroom can take, you can compare suitable options in our range of toilets.

The Order That Saves Mistakes

Toilet shopping gets much easier when you make the decisions in the right order. The plumbing fit comes first. The look comes later.

1. Confirm trap type: S-trap, P-trap, skew trap or universal trap.
2. Measure set-out: the number that makes or breaks compatibility.
3. Choose the style: close coupled, back-to-wall or wall-hung.
4. Check the practical details: projection, footprint and inlet position.
5. Then choose features: rimless, comfort height, soft-close and quick-release seats.

Toilet Buying Checklist at a Glance

Step 1: Know Your Trap Type

Trap type tells you where the toilet waste goes. It is the first thing to identify before ordering, because it decides whether the new toilet can connect to the existing outlet.

S-Trap Toilets

S-trap toilets discharge through the floor. Look for the waste pipe disappearing down into the tiles or floor behind the pan.

P-Trap Toilets

P-trap toilets discharge through the wall. Look for the waste pipe going straight back into the wall behind the pan.

Skew Trap Toilets

Skew trap toilets suit outlets that are offset to the left or right. This is the classic "my waste is not centred" scenario. If skew is involved, confirm left-hand or right-hand as you face the toilet.

Universal Trap Toilets

Many modern toilet suites are sold as universal or uni-trap, meaning they can often be configured for either S-trap or P-trap installation with the correct connector. Useful, yes. Magic, no. You still need to confirm the measurement range, inlet position and physical fit.

For the deeper version, read the full guide to S-trap vs P-trap vs skew trap toilets.

Step 2: Measure Toilet Set-Out Properly

Set-out is the measurement that decides whether a toilet will physically line up with your outlet. This is where a lot of wrong orders happen, especially when people mix up horizontal and vertical measurements.

S-Trap Set-Out

S-trap set-out is horizontal. Measure from the finished wall to the centre of the floor waste.

P-Trap Set-Out

P-trap set-out is vertical. Measure from the finished floor to the centre of the wall waste.

Always measure from finished surfaces like tiles, not bare framing, bare slab or unlined wall positions. In a renovation, that difference can be enough to throw the install off.

For the step-by-step version, read how to measure toilet set-out in Australia.

Step 3: Choose the Toilet Style That Matches the Job

Once trap type and set-out are clear, style selection becomes much easier. The style should match both the bathroom and the install reality.

Close Coupled Toilets

Close coupled toilets are the classic pan and cistern setup. They are usually best for simple replacements, straightforward installs and easy maintenance access.

Back-to-Wall Toilets

Back-to-wall toilets give you a sleeker look where the pan sits tight to the wall. They suit modern bathrooms and make cleaning around the back of the pan easier, but measurements matter more.

Wall-Hung Toilets

Wall-hung toilets mount to an in-wall frame and float above the floor. They suit full renovations, premium bathrooms and maximum floor cleaning, but they are not usually a simple swap.

For the full breakdown, read back-to-wall vs close coupled vs wall-hung toilets.

Step 4: Rimless, Comfort Height and WELS Checks

Rimless Toilets

Rimless toilets usually make the bowl easier to access for cleaning because the internal rim is simplified. The "worth it" part comes down to how much you value easier cleaning day to day.

Comfort Height vs Standard Height

Comfort height can feel better for taller users or anyone who wants an easier sit and stand. Standard height can feel more natural for children, shorter users or people who prefer a lower seat position.

WELS Star Rating in Australia

Check the WELS star rating if you want to compare water efficiency between toilet suites. It is not the only buying factor, but it can help you compare water use over time.

Projection and Footprint

Projection is how far the toilet extends into the room. Footprint is the base shape that sits on the floor. Both matter, especially when replacing an older toilet where floor marks, silicone lines or untiled patches may be exposed once the old pan is removed.

Step 5: Toilet Seats, Shape and Features People Regret Not Getting

Even if you are buying a full toilet suite, the seat still matters. If you are replacing just the seat, it matters even more.

The Two Big Seat Mistakes

• Wrong shape: D-shape, oval and round seats are not automatically interchangeable.
• Wrong fixing type: top-fix and bottom-fix seats suit different pans and hinge access.

Features That Are Actually Worth It

• Soft close: stops the slam and feels better day to day.
• Quick release: makes proper cleaning much easier.

If you are replacing just the seat, start with toilet seats, then use the toilet seat replacement guide to check shape, hinge spacing and fixing type before ordering.

Quick Decision Cheat Sheet

• If you are not renovating and want a simple swap, a close coupled toilet is often the easiest path.
• If you want a modern clean look without going full in-wall, back-to-wall is usually the sweet spot.
• If you are doing a full renovation and want maximum cleanability, wall-hung is the premium option.
• If you are unsure on compatibility, trap type and set-out come first, always.
• If the pan and cistern are fine but the seat is tired, a replacement toilet seat may be all you need.

Once your measurements are clear, compare options across the main toilet categories:

• Toilets
• Close coupled toilets
• Back-to-wall toilets
• Wall-hung toilets
• Toilet seats

More Toilet Buying Guides

If you are still working through the right toilet setup, these guides cover the other decisions that usually come up before ordering.

• S-Trap vs P-Trap vs Skew Trap Toilets
• How to Measure Toilet Set-Out
• Toilet Seat Replacement Guide
• Replacing a Toilet Without Moving Plumbing
• Back-to-Wall vs Close Coupled vs Wall-Hung Toilets

Frequently Asked Questions

How do I choose the right toilet in Australia?

Start with the plumbing fit before the style. Confirm the trap type, measure the set-out from finished surfaces, check the projection and water inlet position, then choose between close coupled, back-to-wall or wall-hung toilet styles.

Can I replace a toilet without moving plumbing?

Often yes, if you match the existing trap type, set-out, projection, footprint and water inlet position. Like-for-like toilet replacements are usually the smoothest option.

What is the difference between S-trap, P-trap and skew trap toilets?

An S-trap toilet discharges through the floor, a P-trap toilet discharges through the wall, and a skew trap toilet suits an outlet that is offset to the left or right.

What is toilet set-out?

Toilet set-out is the measurement from a finished wall or finished floor to the centre of the waste outlet. For S-trap toilets it is measured horizontally from the finished wall to the floor waste centre. For P-trap toilets it is measured vertically from the finished floor to the wall waste centre.

Which toilet style is easiest to replace?

Close coupled toilets are usually the easiest replacement path because the pan and cistern setup is familiar, serviceable and common in Australian bathrooms.

What is the easiest toilet to keep clean?

Back-to-wall and wall-hung toilets usually make floor cleaning easier because there are fewer awkward gaps around the base. Rimless toilet bowls can also make inside-bowl cleaning simpler.

Are toilet seats universal?

Not always. Toilet seat fit depends on pan shape, hinge spacing, fixing type and the specific seat design. Measure and check the pan before ordering a replacement seat.