The Complete Guide to Accessible Bathrooms in Perth

What makes a bathroom accessible?

An accessible bathroom is one that a person can use safely and independently - or with the assistance they need - regardless of their mobility, balance, strength or the equipment they rely on. That is a functional definition, not a compliance definition, and it matters because many bathrooms that technically meet a standard are still difficult to use in practice.

The Australian Standard AS 1428.1 sets dimensions and specifications for accessible design in buildings. For residential bathrooms, the relevant provisions cover floor space, doorway width, sanitary fixture heights, reach ranges and the slip resistance of floor surfaces. These are minimum standards; a well-designed accessible bathroom will exceed them in several areas.

What does an accessible bathroom mean for a Perth home? It means a room where someone in a wheelchair can turn around without assistance, where shower entry requires no step, where the toilet height allows comfortable sitting and rising, and where every tap and fitting can be operated with one hand and without grip strength.

Room dimensions and layout

The minimum floor area for a fully accessible bathroom that allows a wheelchair user to turn in place is 1,800 x 1,800 mm of clear floor space. This is separate from any fixed fixtures - the turning space must be clear of the toilet, basin and shower when those items are in their normal position.

In practice, a bathroom with a 1,200 mm x 900 mm shower zone, a wall-hung toilet and a basin on the opposite wall, in a room of approximately 2,400 x 1,800 mm, provides the minimum turning space. Larger rooms allow more flexibility in layout and reduce the precision required in fixture placement.

The relationship between the toilet and the shower matters particularly for transfer - the movement from a wheelchair to the toilet and back. AS 1428.1 specifies a 900 mm clear zone beside the toilet on the transfer side, and the shower entry should be within reach of the toilet transfer position wherever possible.

• Minimum bathroom area: 2,400 x 1,800 mm for a wheelchair user
• Clear turning circle: 1,800 mm diameter, unobstructed
• Transfer space beside toilet: 900 mm wide on the approach side
• Shower zone minimum: 1,200 x 900 mm for a shower chair
• Doorway clear width: 810 mm minimum (a standard 820 mm door gives about 780 mm clear)
• Door swing: outward-swinging preferred, or pocket door, to keep internal space clear

Doorway width and entry

A standard 820 mm internal door in a Perth home provides around 780 mm of clear width when open, because the leaf itself takes up about 40 mm. A manual wheelchair needs at least 810 mm clear to pass through without difficulty. Walking frames (wheelie walkers) typically need 760 mm minimum.

Widening a doorway costs $3,000 to $4,000 per door in Perth as part of a larger job, and $4,000 to $5,000 as a one-off. Perth's double brick construction is the reason the cost is higher ($3,000 to $4,500) because of the lintel work required.

Offset hinges are a lower-cost first step - they swing the door completely clear of the frame and can add 40 to 50 mm of clear width. They cost $150 to $350 installed and work in most door frames without structural changes.

The shower: layout, entry and dimensions

A level-entry shower - no hob, no step - is the foundation of an accessible bathroom. The shower entry is flush with the bathroom floor (or within 10 mm), and the shower floor is sloped to a drain at a gradient of 1:60 to 1:80.

The minimum useful size for a shower used with a shower chair is 900 x 900 mm. For a wheelchair transfer shower - where the person transfers from wheelchair to shower chair inside the shower - a minimum of 1,200 x 900 mm is needed, with the wheelchair parked beside the open entry.

The drain position should allow the gradient to flow naturally from the entry toward the back of the shower. A linear drain along the back or side wall simplifies the gradient to one direction. A central point drain requires the floor to slope from all four sides and is harder to achieve at the correct gradient.

• Entry threshold: flush or maximum 10 mm lip
• Floor gradient: 1:60 minimum to drain (1:80 is the code minimum, 1:60 is recommended practice)
• Shower size minimum (shower chair): 900 x 900 mm clear
• Shower size for wheelchair transfer: 1,200 x 900 mm clear
• Waterproofing: AS 3740 compliance throughout the wet area
• Drain type: linear channel or central point - linear is simpler to gradient correctly
• Slip rating: P4 minimum, P5 recommended for shower floors

Grab rails: position, specification and installation

Grab rails are not accessories - they are structural elements of an accessible shower and toilet. Their positions should be determined by the movements the person makes: stepping in, sitting down, standing up, reaching for soap. The positions in a design guide are starting points; the final positions should be measured against the individual user.

Rail diameter should be 32 mm - the Australian standard for a grab bar. This diameter allows a secure grip for most hand sizes. Larger diameters are harder to grip; smaller diameters provide less mechanical advantage.

Rails must be fixed into wall studs, masonry or purpose-installed blocking. If the wall is plasterboard or fibre cement board with no backing, a backer board must be installed first. The fixing must carry a lateral load of at least 1,100 N (approximately 112 kg force) without pulling out.

• Horizontal shower rail: 840 - 900 mm from floor, minimum 600 mm long
• Vertical shower rail: 900 mm height at the entry, for steadying on entry and exit
• Angled rail beside toilet: 800 mm at the low end, angled upward at 45 degrees
• Horizontal rail behind toilet: 800 - 840 mm, to push up from
• Rail diameter: 32 mm standard
• Wall fixing load rating: minimum 1,100 N lateral load
• Finish: stainless steel or powder coat to match other fixtures

Toilet: height, position and clearance

The accessible toilet pan height is 450 mm from the floor to the top of the seat. This is the height of a standard chair and allows comfortable sitting and rising with less knee and hip effort than a standard 400 mm pan.

The pan should be positioned so that the centreline of the toilet is 450 to 500 mm from the side wall - this allows the user to approach from the front and turn to sit. A 900 mm clear zone is needed on the transfer side (the side a wheelchair user approaches from). If the transfer side is against a wall, the transfer is from one side only; if there is space on both sides, transfer is possible from either.

The cistern type affects rail positioning. A close-coupled cistern (sitting directly on the pan) typically prevents a horizontal rail from being installed behind the toilet at the correct height. A back-to-wall cistern (concealed in the wall) solves this and allows a rail at the correct position. The extra cost of a back-to-wall cistern is $400 to $900.

Basin: height, reach and clearance

The accessible basin rim height is 800 to 820 mm. The basin should provide a minimum 650 mm knee clearance underneath, and 820 mm horizontal clear space at the front for a wheelchair to approach.

Wall-hung basins provide the knee clearance that a pedestal basin does not. The plumbing is concealed in the wall or run to the side. The basin depth should be 150 mm or less so a seated user can reach the tap without leaning far forward.

The tap should be a lever mixer positioned at the front of the basin, within easy reach of a seated user. A long lever arm reduces the force needed to operate it.

Floor finishes and visual contrast

The floor of an accessible bathroom must meet AS 4586 P4 minimum for the dry area and P5 for the shower zone. These are not decorative choices - they are safety requirements. Many attractive bathroom tiles achieve only P3 when wet and are not suitable for an accessible bathroom floor.

Colour contrast between floor and walls assists people with low vision to navigate the space. AS 1428.1 recommends a minimum 30 percent luminance contrast between the floor and wall surfaces. A mid-tone floor against lighter walls, or a darker floor against any wall colour, provides this contrast.

The contrast between the toilet pan and the floor also aids orientation. A white pan on a mid-tone floor has adequate contrast. A white pan on a white floor does not - a contrast bath mat or a floor tile change in that zone is a low-cost fix.

Hot water and temperature control

The WA Plumbing Code sets the maximum hot water delivery temperature from the hot water system at 50 degrees Celsius for residential properties. However, at the shower head, a thermostatic mixer can reduce this to a pre-set 38 degrees, providing an additional safety layer.

For accessible bathrooms used by people with reduced skin sensitivity, a thermostatic mixer is strongly recommended. At $900 to $1,800 installed, it is a moderate additional cost on a full bathroom project but eliminates scald risk entirely.

Tap outlets should also be checked: a tap that takes several seconds to deliver hot water (because the pipes are long) may be set too low in temperature and can support bacterial growth. A plumber can advise on the correct balance between legionella prevention (requiring hot water system temperatures above 60 degrees) and scald prevention at the outlet.

Order of works

An accessible bathroom renovation follows a specific sequence. Getting the order wrong wastes time, causes rework, or results in fixtures being installed before the waterproofing is confirmed, which leads to callbacks.

• 1. Strip: remove existing fixtures, tiles, and wall linings as needed
• 2. Structural: doorway widening, drain relocation, wall blocking for rails
• 3. First fix plumbing: new drain positions, water supply rough-in
• 4. Wall lining: moisture-resistant sheeting, cement board in wet areas
• 5. Waterproofing: membrane application and curing (24 - 48 hours minimum)
• 6. Floor gradient: screed to fall, confirmed with level before tiling
• 7. Tiling: floor first, then walls
• 8. Second fix plumbing: fixtures, tapware, cistern
• 9. Grab rails and accessories: after tiling is complete
• 10. Final inspection and waterproofing certificate

Getting a quote for an accessible bathroom in Perth

An accurate quote for an accessible bathroom requires a site visit. A reputable contractor will measure the room, assess the wall substrate, check the drain position and determine whether doorway widening or structural work is needed before pricing the job.

AccessAble designs and builds accessible bathrooms under one roof in Perth. The whole project - design, plumbing, tiling, rail installation and sign-off - is managed by one team rather than being coordinated between multiple trades. That reduces the risk of specification being lost between contractors and means one point of contact throughout.

You can request a quote at any point, describe what you need, and get a price back at no cost and with no obligation. A $149 home safety audit covers the whole house and provides a written report on the changes that would make the most difference.