Designing for equity: Gender-responsive restroom policy in Phnom Penh’s public spaces

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By Top Viphallin

IPF

Future Forum's junior research fellow, Top Viphallin, has published a new commentary on gender-responsive restroom policies in Phnom Penh’s public spaces. Check out the full article below!

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Modern urban development often masks a systemic failure: the "invisible queue" that hinders true inclusivity. By prioritizing geometric floor-area equality over functional reality, architectural planning ignores the compounding "time tax" imposed by biological and social factors. This commentary addresses how traditional design fails to provide gender-responsive facilities, advocating for a shift toward outcome-based equity in the built environment.

Policy issue

In the rapidly developing urban landscape of Phnom Penh, modern skyscrapers, and sprawling shopping malls are reshaping the city’s skyline at an unprecedented pace. While male and female public restrooms are often allocated equal floor space or a 1:1 ratio of rooms, women consistently experience significantly longer wait times, often stretching out into corridors and public walkways.

This disparity is not a matter of personal efficiency or a "cliché" of social behavior; it is a structural failure of architectural and policy-based gender bias. To achieve true urban equity, Phnom Penh’s public space policies must pivot from the outdated concept of "equal floor area" toward a model of functional equity and equity of outcomes. This requires mandating a significantly higher ratio of female-to-male fixtures and the integration of universal family spaces that acknowledge the social reality of caregiving in Cambodia.

Currently, Cambodia’s Ministry of Land Management, Urban Planning, and Construction provides broad guidelines for wastewater and sewage (such as Sub-decree 235) but lacks a specific, publicly–accessible municipal code that mandates fixture ratios for gender parity. In the absence of local mandates, developers in Phnom Penh often default to a 1:1 area ratio. This "geometric equality" ignores the empirical reality that women require more time and different facilities than men.

International standards, such as the ASEAN Public Toilet Standard, emphasize cleanliness and safety but stop short of prescribing exact gender-based ratios. For a city like Phnom Penh, which aims to be a modern regional hub, relying on vague international cleanliness standards is insufficient for managing the density of its growing population.

The empirical case for the "equity ratio"

The argument for increasing female restroom capacity is rooted in a combination of biological science, behavioral psychology, and architectural efficiency. To understand why "equal space" is inherently unequal, one must examine the specific factors that contribute to the "Time Tax" paid by women in public spaces.

The biological "time tax"

Research consistently shows that women take significantly longer to use a restroom than men. Studies cited by The Guardian (2018) and TIME Magazine indicate that women take 90 seconds on average, compared to 40 seconds for men—a 2.25x time difference. This is not a choice; it is a biological necessity.

Women face unique requirements including menstruation management, which involves additional time for sanitization, changing products, and disposal. Analytical queuing is a function of both duration and frequency. Biological factors like menstruation and pregnancy necessitate longer, more frequent visits, creating a multiplier effect on occupancy load. This increasing demand generates a structural "time tax," where increased service times and arrival rates mathematically guarantee systemic bottlenecks for women. As a result, without a 2:1 or 3:1 fixture ratio, women will be taxed for their biology through lost time and physical discomfort.

The geometric inefficiency of stalls vs. urinals

A major flaw in the 1:1 floor area design is the difference in fixture density. A male restroom of 50 m² can accommodate a high number of urinals alongside a few stalls. Urinals are space-efficient and allow for a high throughput of users. Conversely, a female restroom of the same 50 m² must consist entirely of enclosed stalls.

Stalls require more square footage for doors to swing, for privacy partitions, and for the user to navigate the space. Therefore, if a male and female restroom are the same size, the male restroom will almost always have a higher number of functional stations. To achieve throughput parity, the female restroom must physically be larger or contain more fixtures to match the speed at which the male restroom clears its queue.

The caregiver burden and social load

In the Cambodian socio-cultural context, women are disproportionately the primary caregivers for children, the disabled, and the elderly. When a mother takes two children into a stall, the user load on that single fixture triples, and the time spent inside doubles or triples as she assists them. This is what urban planners call "social load." Current designs in Phnom Penh’s older markets and even some newer malls do not account for the fact that a female stall is rarely serving just one person.

Implementation: A proposed solution for Phnom Penh

To address these disparities, the Phnom Penh Municipality should adopt a comprehensive implementation framework that moves away from "one size fits all" public facilities.

A. Mandate a 2:1 or 3:1 fixture ratio

Drawing from Singapore’s Code of Practice on Environmental Health, which is widely considered the gold standard in the region, Phnom Penh should update its building permits to require that for every 10 fixtures in a male restroom (e.g., 7 urinals and 3 stalls), the female restroom must provide at least 20 stalls. This ratio compensates for the 2.25x time difference and ensures that the "wait time" for both genders is mathematically equalized.

B. Include gender-neutral or family restrooms

Implementation must include the mandatory provision of a gender-neutral "family restroom." According to the International Plumbing Code (IPC) updates, family restrooms are essential for modern urbanity.

In Phnom Penh, where multi-generational outings are common, a family restroom allows a father to change a baby’s diaper or a daughter to assist an elderly father without entering a gender-segregated space. This removes the burden of childcare from the female restroom, significantly reducing the "caregiver queue" and making the city more accessible for fathers who wish to participate in caregiving.

Moreover, gender-neutral restrooms provide essential safety and privacy for LGBTQ+ individuals, particularly transgender and non-binary citizens who face harassment in binary facilities.

By implementing high-privacy, all-gender stalls, the municipality ensures that public infrastructure respects the dignity of every resident, regardless of their family role or gender identity.

C. Menstrual hygiene management (MHM) infrastructure

Policy must move beyond just "stalls" to "amenities." Implementation should require all public restrooms to include:

• Sanitary napkin disposal units in every stall

• Toilet seat cleaning wipe or spray

• A shelf or hook for bags (to keep items off potentially unsanitary floors)

D. Economic incentives and "equity certification"

The city can implement an "Equity Certification" for commercial buildings. Research suggests that inadequate facilities lead to "situational avoidance," where women shorten their stays in commercial areas or avoid certain markets altogether to avoid the discomfort of long queues.

Implementation responsibility

The Ministry of Land Management, Urban Planning, and Construction mandates the 2:1 fixture ratios within national building codes. The Ministry of Health establishes hygiene and Menstrual Hygiene Management (MHM) standards. The Ministry of Women’s Affairs oversees gender-neutral restroom designs for caregivers and non-binary people. Finally, the Ministry of Economy and Finance provides tax incentives for "Equity Certified" developers, while the Phnom Penh Municipal Administration enforces these regulations during the local permit approval process.

Counterargument: The cost of space

The primary opposition to these changes is the economic cost of floor area. In premium real estate areas like Daun Penh or BKK1, every square meter counts. Developers argue that increasing restroom size reduces "leasable area," thereby lowering the building's net operating income.

This is a short-sighted economic view. Recent mathematical simulations in Management Science (2025) demonstrate that converting a small portion of male-only space into unisex or female-priority space can lead to a Pareto Improvement, a scenario where the overall efficiency of the building increases.

Furthermore, the public health cost of inadequate sanitation is a hidden drain on the economy. Inadequate access for women leads to higher rates of urinary tract infections (UTIs) and decreased public participation. According to UN Women, inclusive infrastructure is a prerequisite for women’s economic empowerment; if women cannot navigate the city comfortably, they cannot participate in the economy fully.

Parting message

As Phnom Penh continues its journey toward becoming a "smart city", we must remember that a city is only as smart as its most basic infrastructure. Moving from "equality" to "equity" in restroom design is a small change in a floor plan that creates a massive change in the quality of life for half the population.

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