1500mm vs 1700mm Bath: Which Size Is Better for an Australian Bathroom?

If you are choosing between a 1500mm bath and a 1700mm bath in Australia, the short answer is simple: 1500mm usually suits compact bathrooms, ensuites and bath-shower combinations better, while 1700mm is the stronger choice for a standard family bathroom where adult comfort matters more.

The right bath size is not just about what looks good in a showroom. It affects how open the room feels, how easily you move around the vanity and toilet, how practical the bath is for children or regular soaking, and whether the final layout feels calm or cramped.

At a glance: 1500mm vs 1700mm

When a 1500mm bath is the smarter choice

A 1500mm bath is often the safer decision when you are trying to make a bathroom work hard without feeling overloaded. It is especially useful when the bath needs to share the room with a toilet, a vanity and a shower screen without squeezing the circulation space.

• You are renovating a compact main bathroom or ensuite.
• The bath will sit inside a bath-shower combination.
• You want to preserve more usable floor area in front of the vanity or toilet.
• The bath is mainly for children, occasional use or resale flexibility rather than long adult soaks.
• You are replacing an older bath and want an easier fit without redesigning the whole room.

In many Australian homes, that makes 1500mm the practical renovation choice. It gives you the function of a bath without letting the bath dominate the room.

When a 1700mm bath is worth the extra length

A 1700mm bath usually makes more sense when you have enough wall length and want the bath to feel like a genuine comfort feature rather than a layout compromise. It is the better option when adults in the household will actually use the bath regularly.

• Your bathroom is a standard family size rather than a tight apartment-style layout.
• You want a better chance of a comfortable adult soak.
• The bath is an intentional part of the design, not just a box to tick.
• You have enough room to keep the surrounding layout balanced.
• You do not want the bath to feel undersized next to a larger vanity, wider tile layout or more open room.

If the space supports it, a 1700mm bath often gives the room a more settled feel. The key is making sure that extra length does not create tighter pinch points elsewhere.

Bath type matters just as much as bath length

The same length can behave very differently depending on whether the bath is freestanding, back-to-wall or inset. That matters when you are comparing real bathroom layouts instead of just product specs.

• Freestanding baths usually ask for more visual breathing room. In a tight bathroom, a freestanding 1700mm bath can look beautiful but still make the room feel busy.
• Back-to-wall baths are often a smarter compromise when you want a cleaner look without giving up as much usable space around the bath.
• Inset baths are often the most practical option in bath-shower combinations and replacement projects because they work more efficiently with walls, screens and existing plumbing positions.

So if you are choosing between sizes, do not compare length alone. Compare size plus bath type plus room layout.

How to measure before you buy

A bath that fits on paper can still feel wrong once the room is tiled, the vanity is installed and the shower screen is in place. Before you commit, measure the room as a finished space, not an empty shell.

1. Measure the actual wall length where the bath will sit.
2. Check what happens to the space in front of the bath once the vanity, toilet and door swing are accounted for.
3. If the bath shares space with a shower, think about where the screen, mixer and shower rose will land.
4. If you are choosing a freestanding bath, allow for cleaning access, visual bulk and how the tapware will be installed.
5. If this is a replacement project, compare the new bath shape with the old one rather than assuming the same nominal length will feel the same.

Simple rule: If a 1700mm bath forces the rest of the bathroom to become awkward, the 1500mm option is usually the better renovation decision. If the room still feels balanced with a 1700mm bath, the extra length is often worth it.

Common mistakes to avoid

• Choosing the longest bath that fits the wall without checking the rest of the room.
• Assuming a freestanding bath and an inset bath use space in the same way.
• Buying around showroom appearance without thinking about daily cleaning and movement.
• Treating the bath as the hero item when the bathroom really needs better balance overall.

Final recommendation

For most compact Australian bathrooms, a 1500mm bath is the more forgiving option. For a standard family bathroom where comfort is part of the brief, a 1700mm bath is usually the stronger long-term choice.

If you are still torn, compare the full layout rather than the bath in isolation. The best bath is the one that keeps the whole bathroom working well, not just the one with the bigger number on the spec sheet.

Planning a renovation? Start with the bath size that suits your room first, then choose the bath style, tapware and shower layout around it.