Bathtub Size Guide 2026

Bathtubs in Australia typically range from 130 cm to 190 cm in length, with small baths (130-150 cm) suiting compact bathrooms, medium baths (150-170 cm) covering most standard renovations, and large baths (170-190 cm) suited to master ensuite or statement bathroom settings. Getting the right bathtub size for your bathroom matters from the start, as the wrong choice affects not just the fit but the plumbing rough-in, floor loading, and how every other fixture in the room sits around it.

Whether you are renovating an existing bathroom or building new, measuring your floor space carefully before you buy is the single most important step you can take.

What Types of Bathtubs Are Available in 2026?

Bathtubs in 2026 come in 4 common installation types:

1. Freestanding baths (sit away from all walls; the bath itself is the feature)
2. Back-to-wall baths (one end or back butts against the wall; plumbing is concealed behind)
3. Inset or built-in baths (recessed into a tiled alcove or surround on three sides)
4. Corner baths (designed to fit into a 90-degree corner of the room)

There are 4 common bathtub shapes:

1. Oval or elliptical (the most popular freestanding shape in Australia)
2. Rectangular (clean-lined; suits contemporary and minimalist bathrooms)
3. Slipper (raised at one or both ends for a reclining soak; single or double slipper)
4. Corner (square or angled; designed to maximise corner floor space)

Below is a guide on the most common bathtub sizes, dimensions, shapes, and materials available in Australia.

Small Bathtub Sizes & Dimensions

Small bathtubs suit compact bathrooms, apartments, secondary bathrooms, and any room where space is at a premium. In Australian homes, small baths are common in older terraces, inner-city apartments, and family bathrooms where floor space is shared with a shower recess and vanity.

A 130 cm to 150 cm bath can work well where a larger model simply would not fit, and back-to-wall or inset installation styles are typically more practical than freestanding at this size.

Rectangular Small Bathtub:

130 cm to 150 cm (length) x 70 cm to 75 cm (width) x 40 cm to 45 cm (height). Weight for acrylic models typically 25 kg to 40 kg; cast stone and cast iron significantly heavier.

Freestanding Small Bathtub:

140 cm to 150 cm (length) x 70 cm to 75 cm (width) x 52 cm to 58 cm (height). Freestanding small baths need at least 10 cm to 15 cm of clearance on all sides for access and cleaning.

Small Inset or Built-in Bathtub:

120 cm to 140 cm (length) x 70 cm to 75 cm (width). Designed to fit into a tiled alcove; confirm the internal usable length (not just the outer footprint) before ordering.

Compact Corner Bathtub:

120 cm to 140 cm (length) x 120 cm to 140 cm (width). Corner baths require more floor area than a rectangular bath of equivalent length; the square footprint takes up significant room in a small bathroom.

Small Clawfoot or Slipper Bathtub:

130 cm to 140 cm (length) x 70 cm to 75 cm (width). Clawfoot and slipper styles at this length are less common but suit heritage-style bathrooms in older Australian homes where a longer model is not practical.

• Length: 130 cm to 150 cm
• Width: 70 cm to 75 cm (rectangular); wider for corner formats
• Height: 40 cm to 58 cm depending on style
• Weight: 25 kg to 40 kg (acrylic); 120 kg to 180 kg (cast stone or cast iron)
• Minimum floor space: Allow at least 10 cm to 15 cm clearance on all accessible sides

The Keeto Back-to-Wall Acrylic Bath 1300mm from Schots is a good example at this size, measuring 130 cm in length with a 177L capacity and a net weight of 37 kg.

Medium Bathtub Sizes & Dimensions

Medium bathtubs are the most commonly sold size in Australian homes and suit the majority of standard bathroom renovations. They work well as the primary bath in a family bathroom or main ensuite, and the 150 cm to 170 cm range gives a comfortable soaking length for most adults.

At this size, all four installation types (freestanding, back-to-wall, inset, corner) are well represented in the Australian market, giving the widest range of style and price options.

Standard Medium Rectangular Bathtub:

160 cm to 170 cm (length) x 70 cm to 75 cm (width) x 38 cm to 45 cm (height). The most common size in Australian bathroom supply stores; suits standard alcove or inset installation.

Freestanding Medium Bathtub:

160 cm to 170 cm (length) x 75 cm to 80 cm (width) x 52 cm to 60 cm (height). Freestanding baths at this size suit a bathroom floor area of at least 2.5 m x 2.0 m to allow comfortable access on all sides.

Medium Inset or Built-in Bathtub:

150 cm to 160 cm (length) x 70 cm to 80 cm (width). Confirm the internal soaking length in addition to the external footprint, as the rim width varies between models and affects how much usable space you actually get.

Standard Corner Bathtub:

150 cm x 150 cm (square format). Corner baths at this size suit a bathroom alcove or corner with at least 1.6 m of clear wall space on each side.

Medium Deep Soaking Bathtub:

150 cm to 170 cm (length) x 75 cm to 85 cm (width) x 55 cm to 65 cm (height interior depth). Deep soaking baths hold significantly more water; factor in structural floor loading for stone or cast iron models above 100 kg.

• Length: 150 cm to 170 cm
• Width: 70 cm to 85 cm (varies by style)
• Height: 38 cm to 60 cm depending on style and material
• Weight: 34 kg to 50 kg (acrylic); 130 kg to 145 kg (cast stone); up to 145 kg (cast iron)
• Water capacity: Approximately 240 L to 300 L depending on depth and internal dimensions

The Marietta 170cm Freestanding Acrylic Bath and the Nero Solid Surface Bath 1550mm from Schots both sit in this category, offering very different weights and aesthetics at similar lengths.

Large Bathtub Sizes & Dimensions

Large bathtubs are the statement piece in a master bathroom or luxurious ensuite. They suit larger floor areas, couples bathing together, or anyone who wants a genuinely generous soaking experience.

At 170 cm to 190 cm, weight becomes a key consideration, particularly for cast iron and cast stone options which can exceed 140 kg empty. Floor preparation and structural loading should be discussed with your builder or plumber before purchasing.

Standard Large Rectangular Bathtub:

180 cm to 190 cm (length) x 80 cm to 90 cm (width) x 40 cm to 50 cm (height). At this length, a dedicated bathroom alcove of at least 190 cm x 100 cm is needed for an inset installation.

Freestanding Large Bathtub:

180 cm to 190 cm (length) x 85 cm to 90 cm (width) x 55 cm to 65 cm (height). A freestanding bath of this size needs a minimum bathroom floor area of approximately 3.0 m x 2.5 m to sit comfortably as a feature without crowding the room.

Large Inset or Built-in Bathtub:

170 cm to 180 cm (length) x 75 cm to 90 cm (width). Large inset baths suit master bathrooms with purpose-built tiled surrounds; allow at least 5 cm to 10 cm of extra length and width in the framed alcove for installation tolerances.

Large Corner Bathtub:

160 cm to 180 cm (length) x 160 cm to 180 cm (width). Large corner baths require a substantial floor area and are best suited to bathrooms designed around them from the planning stage.

Large Clawfoot or Slipper Bathtub:

170 cm to 180 cm (length) x 75 cm to 85 cm (width) x 55 cm to 65 cm (height including feet). Cast iron at this size typically weighs 135 kg to 145 kg empty; confirm your floor loading capacity before installation.

• Length: 170 cm to 190 cm
• Width: 75 cm to 90 cm (varies by style)
• Height: 40 cm to 65 cm depending on style and feet
• Weight: 42 kg to 50 kg (acrylic); 135 kg to 145 kg (cast iron); up to 140 kg (cast stone)
• Water capacity: Approximately 280 L to 340 L or more

The 170cm Double Ended Cast Iron Bath with Feet from Schots is a premium example at 170 cm L x 77 cm W x 57 cm H, weighing 142 kg, suited to a master bathroom with a reinforced floor.

Bathtub Size Comparison at a Glance

Use this table to compare all three size categories before making a purchase decision. All dimensions are typical ranges based on products available in the Australian market.

Which Bathtub Installation Type Is Right for You?

Before choosing a size, most buyers need to settle on the installation type. The four options differ significantly in floor space requirements, renovation complexity, plumbing visibility, and the overall look they produce.

Choose Your Bath Type

Use these quick scenarios to find the right starting point for your renovation.

Choose a freestanding bath if you want the bath to be the centrepiece of the room, you have enough floor area to allow at least 10 cm to 15 cm of clearance on all sides, and you are happy to have the tapware visible beside the bath as a freestanding mixer. Freestanding baths work well in both new builds and renovations where no existing alcove is in place.

Choose a back-to-wall bath if you want a clean, contemporary look with all plumbing concealed but you do not have the floor space for a fully freestanding model. Back-to-wall baths sit against one wall or panel and give the visual impression of a freestanding bath with a smaller footprint. Good for bathrooms where space is moderate but style matters.

Choose an inset or built-in bath if you are doing a full bathroom renovation and want the lowest possible purchase price per centimetre of bath length. Inset baths sit in a tiled alcove and share walls on three sides, which keeps the overall floor impact small. They are the most practical choice for a standard family bathroom where function and budget are priorities.

Choose a corner bath if you have a square or near-square bathroom and want to maximise the bathing area without taking up the full length of one wall. Corner baths suit bathrooms specifically designed around them; retrofitting a corner bath into an existing layout requires more planning and usually more renovation work.

Additional Bathtub Considerations

1. Measure your floor space before ordering. Take the length and width of your available floor space and subtract the clearances you need around the bath. For freestanding styles, allow a minimum of 10 cm to 15 cm on all sides; for inset and back-to-wall styles, confirm the rough-in dimensions required by your plumber. Getting this wrong before tiling is an expensive mistake.
2. Check floor loading for heavy baths. A cast iron or cast stone bath can weigh 130 kg to 145 kg before a single litre of water is added. Full of water, the total load can exceed 400 kg in one area of the floor. Older Australian homes with timber suspended floors may require structural reinforcement; always discuss with your builder or structural engineer before purchasing.
3. Factor in the plumbing rough-in position. The waste outlet position (centred, offset, or end) varies between bath models and needs to align with your existing or planned plumbing rough-in. An off-centre or end waste on a stone bath may require floor preparation before tiling and waterproofing. Confirm this with your plumber before the bath is ordered and paid for.
4. Allow for installation access. Large baths, particularly cast iron and stone models, require careful planning for delivery and installation. A 142 kg cast iron bath through a narrow hallway or up a flight of stairs may need a removalist with equipment. Measure doorways, hallways, and any tight turns on the path from the delivery point to the bathroom.
5. Confirm Australian compliance. The bathtub itself does not require WaterMark certification, but its waste fitting and any connected tapware do, and these must be installed in accordance with the Plumbing Code of Australia and AS/NZS 3500.2. Tapware is separately certified to AS/NZS 3718. Always check product compliance documentation and discuss with your licensed plumber before installation.

Common Bathtub Materials

The material a bathtub is made from affects its weight, warmth, durability, maintenance requirements, and overall appearance. Acrylic remains the most widely sold material in Australian bathroom supply stores, but cast stone and cast iron both offer significant advantages for buyers who are after a premium result.

Acrylic

Acrylic baths are the most common material in Australia and cover a broad range of styles and price points, from compact back-to-wall insets to large freestanding oval baths. Quality acrylic baths use UV-stabilised sanitary-grade acrylic, often reinforced with Lucite MMA, and sit on a built-in steel support frame with adjustable feet.

Acrylic is lightweight compared to stone or cast iron, which makes delivery and installation considerably more straightforward, particularly on upper floors or in homes without direct ground-level access.

Cast Stone (Solid Surface)

Cast stone baths, sometimes listed as solid surface or stone resin, are a composite material made from crushed stone and resin that is cast into bath shapes. The matte white colour runs through the full body of the material rather than being a surface coating, giving it a consistent, high-end appearance that suits contemporary and minimalist Australian bathroom styles.

The key thing to understand dimensionally is weight. Cast stone baths at 155 cm to 165 cm can weigh 130 kg to 140 kg, which has real implications for floor preparation and delivery logistics, particularly in multi-storey homes.

Cast Iron

Cast iron bathtubs are the original premium material and remain a popular choice in Australian homes for their heat retention, durability, and timeless aesthetic. They are typically finished with a vitreous enamel or porcelain interior, which is hard, smooth, and resistant to scratching, and an exterior in a painted or powder-coated finish.

Cast iron is the heaviest bathtub material available, with 170 cm models typically weighing 140 kg to 145 kg. Floor preparation and structural loading must be addressed before installation, and delivery requires a removalist service rather than standard courier.

For most Australian bathroom renovations on standard suspended timber or concrete slab floors, acrylic is the practical and cost-effective choice. Cast stone suits buyers who want a premium contemporary look with better heat retention than acrylic but do not want the full weight penalty of cast iron. Cast iron is the right choice for a statement master bathroom where floor loading has been confirmed and the aesthetic is a priority.

Material Comparison for Purchase Decisions

Top 5 Tips for How to Choose the Right Bathtub Size and Style

Getting the bathtub decision right from the start saves a significant amount of rework, particularly once tiling and waterproofing are underway. Here are the most practical things to confirm before you buy.

1. Measure the floor space, not just the wall length.
   Mark out the bath footprint on the floor with tape and stand in the space around it. For freestanding styles, allow a minimum of 10 cm to 15 cm clearance on all sides for access and cleaning; more is better. For inset and back-to-wall styles, add at least 5 cm to the external bath dimensions when framing the alcove to allow for installation tolerances.
2. Confirm the waste and overflow position before ordering.
   The waste outlet position on a bathtub (end, centre, or offset) needs to match your plumbing rough-in. On cast stone models, an off-centre waste position may require floor preparation before tiling, which must be planned before waterproofing. Always confirm the waste position with your plumber before the bath is ordered.
3. Check the weight against your floor type.
   A 50 kg acrylic bath filled with 200 L of water adds around 250 kg to your floor. A 140 kg cast iron bath filled with 300 L of water adds around 440 kg. Older Australian homes with timber suspended floors often need structural reinforcement for heavier baths; concrete slabs in newer homes typically handle the load without modification, but always confirm with your builder.
4. Match the bath style to the bathroom size, not just personal preference.
   A freestanding oval bath in a 2.0 m x 1.8 m bathroom will dominate the space and leave insufficient room for the vanity, toilet, and door swing. Use a 1:10 scale floor plan (10 cm on paper equals 1.0 m in the room) to lay out the bath position relative to all other fixtures before committing to a style.
5. Plan the tapware position at the same time as the bath.
   Different bath styles require different tapware approaches. Freestanding baths often suit a freestanding bath mixer placed beside the bath. Inset and back-to-wall baths typically use deck-mounted or wall-mounted tapware on the rim or tiled wall. Confirming the tapware approach before tiling, alongside the position of your bathroom vanity and other fixtures, ensures the plumbing rough-in ends up in the right position and avoids costly repositioning later.

Suggested Bathtubs from Schots

Frequently Asked Questions About Bathtub Sizes

What is the standard bathtub size in Australia?

The most common bathtub size in Australian homes is 1500 mm to 1700 mm in length, 700 mm to 800 mm in width, and 380 mm to 600 mm in height, varying by installation style and material. Freestanding baths tend to sit taller than inset models, and cast iron and cast stone baths are typically wider and heavier than acrylic equivalents at the same nominal length.

What size bathtub do I need for my bathroom?

Measure your available floor space first, then subtract the minimum clearances required for the installation style you want. For freestanding baths, allow at least 10 cm to 15 cm on all accessible sides; for inset baths, the bath length should be 5 cm to 10 cm shorter than the alcove length to allow for installation. A 1:10 scale floor plan is the most reliable way to confirm a bath will fit before you order.

How much does a freestanding bath weigh?

An acrylic freestanding bath at 160 cm to 170 cm typically weighs 34 kg to 50 kg empty. Cast stone (solid surface) baths at the same length weigh approximately 130 kg to 140 kg, and cast iron baths at 170 cm typically weigh 140 kg to 145 kg. Full of water, the total load increases significantly, so floor loading must be confirmed for stone and cast iron models before installation.

How much water does a bathtub hold?

Most standard Australian bathtubs hold between 200 L and 340 L, depending on size, depth, and internal shape. A typical medium acrylic freestanding bath holds approximately 240 L to 280 L; deep soaking and large cast iron baths can hold 300 L to 340 L or more. These water volumes add significantly to the floor load, which is why structural assessment matters for heavy baths.

Do I need a plumber to install a bathtub in Australia?

Yes. In Australia, all plumbing work connected to a water supply or waste system must be carried out by a licensed plumber. This includes connecting a bathtub waste, overflow, and any associated tapware. The bath itself does not need WaterMark certification, but the waste fitting and tapware do, and the installation must comply with the Plumbing Code of Australia and AS/NZS 3500.2, as adopted in your state or territory.

Getting the right bathtub for your bathroom renovation comes down to matching the size to your available floor space, confirming the weight against your floor type, and choosing a material that suits your budget and aesthetic. Browse the full Schots baths collection for the current range, or explore our bathroom range including vanities, tapware, and accessories to complete your renovation.

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