EZL first prototypes
Designing the Easy Latrine

Before we launched the Easy Latrine, the existing latrine options for Cambodians consisted of open defecation, dry pits, and expensive concrete bathrooms. Each of these options presented serious barriers to the adoption of rural sanitation. iDE set out to design a marketable toilet that could be manufactured by local producers. We aimed for a sustainable latrine: one that will not collapse, will not degrade year after year, will not fill up prematurely, and will not be abandoned. We recruited Jeff Chapin, while he was on sabbatical from IDEO, to design the latrine.

Using the Human-Centered Design (HCD) approach, we identified the unique needs, desires and barriers of users and produced a product that households wanted to buy and businesses wanted to sell, creating a sustainable solution that can be scaled across the country.

Insight: The patience to save money and invest is remarkable. Villagers will save for a lifetime to build a house and may save 3-6 years to build a latrine.

The Design Process

The design effort began with in-field contextual observations and interviews with the key stakeholders involved in latrine manufacturing, installation and use. The learnings from the observations were distilled and synthesized into a framework that illustrated the potential opportunities for the design offering and showed where it fit into the greater sanitation marketing effort. From there, multiple rounds of brainstorming, prototyping and user testing were undertaken to develop the latrine designs. From the multiple iterations, a design direction emerged that addressed user needs as well as marketing thoughts around how to position the benefits and costs of latrine ownership.

Insight: Children who have emigrated to the city or work in a factory with latrines often motivate their parents to build a latrine and may help finance the latrine.

Prototype Reviews

In the course of the design project, iDE took four trips to the field after the initial user research to review prototypes with stakeholders – villagers, masons, ring producers and retailers. In all cases, a number of 2D and 3D prototypes were shown.

Easy Latrine innovation picture_Fig2

A Complete Product

The Easy Latrine is sold as a packaged do-it-yourself product; customers can purchase, install and use it in the same day.

The Easy Latrine has been recognized by Fast Company, International Design Excellence Awards (IDEA), World Toilet Hall of Fame, the Lipman Family Prize, and the Dubai International Award for Best Practices to Improve the Living Environment.

Read the final design report.


Next Shelter_2
Removing barriers to immediate installation and use
  • 62% of latrines are installed by 6-12 months post-purchase
  • 95% are installed at 15 months
  • 0.2% abandonment rate

While the sales efforts have successfully gotten households to making the first step towards latrine usage, i.e. purchase, it is falling short of instilling a sense of urgency to immediately install and use the latrine. However, from the Pilot Project’s End-of-Project evaluations, it is known that most households do end up installing their latrine eventually. At 450 days (15 months), installation rates are around 95% with a continuing upward trend. This indicates that the vast majority of latrines that are purchased are installed, which is as expected since the latrine cost is a significant cash outlay for a rural household and is not likely to be abandoned. This is confirmed by the most recent SMSU household survey, which shows that abandonment is very low with only 0.2% of households visited having abandoned their latrines.

Despite the eventual installation, there still remains for the household many barriers preventing immediate installation and use. Noteworthy is the strong preference of Cambodian households to build a concrete shelter. Households will wait to install the latrine until they have all the materials and labor ready to install the entire concrete shelter. From a health perspective, it is the underground components that are important for public health, but from the household perspective, it is the superstructure that meets their needs for status and convenience.

In order to decrease the gap between the sales and installation rates, a two-pronged approach would be recommended:

1) Remove the main barrier preventing households from immediate installation and use by developing a packaged shelter product that is easy to purchase, build, and use;

2) Improve behavior change communication interventions to stimulate a greater sense of urgency for the households to install and use.

Next HCD_2
Designing and commercializing a hand washing device

Hand washing is considered one of the most effective ways to reduce diarrheal diseases. Yet there are few commercial hand washing devices for rural Cambodians.  Currently, the most common device used is a ladle and user research indicates ladles are cumbersome and often inconveniently placed far from the site of defecation.

iDE Sanitation Marketing and Scale Up (SMSU) 2.0 program intends to broaden its focus by designing and commercializing a hand washing device. The device will be integrated into iDE’s new latrine shelters and aims to be affordable, desirable, and feasible for local manufacturers. Over the remaining two years of the program, SMSU 2.0 intends to oversee the distribution of 5,000 shelters featuring the integrated hand washing device. In collaboration with its in-house design lab inCompass, iDE will take the following steps:

  • Conduct extensive qualitative field research to identify current practices, beliefs systems, potential behavior change triggers and aspirations associated with hand hygiene rural Cambodia.
  • Create product design guidelines and craft a series of device prototypes soliciting user feedback to test desirability and product functionality.
  • Develop the manufacturing manual and training materials for latrine business owners to produce the device.

To help ensure the efficacy of the product, iDE will conduct user surveys to measure its impact on hand washing habits, hand hygiene beliefs, and the reduction of diarrheal disease.