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Construction manual for the Bathroom Toilet unit

This presentation is about the construction of the Bathroom Toilet units. It aims at an improvement of sanitation in a rural setting. This method is meant to be used in a communal project where inhabitants of a village can be motivated to build a private bathroom for every family around. To achieve that every family can work on its own bathroom facility at the same time, while sharing experience and guidance, a special construction method is used. With wooden copies of the final concrete parts quickly imprints in most soil can be made in or near the yard of every family. These imprints serve as a mold to cast the concrete in for the parts needed.
Work in a village for this project is split up in eight parts, resulting in eight chapters of this manual:

  1. Make the two wooden copies of the concrete parts of the bathroom/toilet, the slap and the gutter
  2. Make two imprints with the wooden slab-copy in the dirt
  3. Make one imprint with the gutter-copy in the dirt
  4. Add concrete to the imprint of the slab: line with paper or plastic, add concrete, reinforce, compact and finish
  5. Add concrete to the imprint of the gutter: line with paper or plastic, add concrete, reinforce, compact and finish
  6. Prepare for composting: build the sub-structure with two cellars under the slabs
  7. Or prepare for a temporary pit top construction that can be moved when the pit is full
  8. Finalizing the Bathroom Toilet unit and to take it into use

Below follows a short description of each chapter and a link to go there.

It will take some time to finalize this presentation, in a way to be of use as a construction manual. In the meantime comments on this subject are welcome through our discussion page.

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First comes the construction together with the local carpenter and its helpers of the molds to shape the concrete parts. In fact they are replica in wood of the later to be cast concrete parts.


With the woodencopy of the slab two imprints are made with moist dirt. With the latest working method, the top of the slap with its face up, is covered with dirt, that is made flat and compacted. Then the slap is quickley turned over with its face down. Moist dirt is then compacted around the wooden copy to form the sides of the imprint.
Finally with great care the wooden copy is lifted off the imprint. Often little repairs are needed of the imprint, this can be done with mud and something flat.
The imprint of the gutter is made in the same way. Again the top of the wooden copy can be filled with dirt, that is compacted and flattened.
Then the gutter-copy is turned over. Dirt is compacted against the sides of gutter copy, then it is lifted off.
Realize these imprints are easely demaged. Keep small children, goats and dogs at a distance. Also keep moist, cover aganst sun and rain.
Best is to continue immediatelly with casting concrete.
Prepare concrete that is like moist mud, not like watery mud. To achieve this, while mixing add water only with small bits. Before adding concrete cover the surface of the imprint in the mud with oiled paper. This prevents the cement water to seep away in the mud. The concrete is reinforced with scrap.
The same method applies for adding concrete to the imprint for the gutter. When adding scrap to reinforce the concrete, take care these bits of wire or sheet metal are not pushed in so hard, that they stick through the concrete into the dirt of the imprint.
All concrete casts shoud get ample time to set and harden. In the mean time keep them wet and prevent damage by animals.

6. Prepare for composting: build the sub-structure with two cellars under the slabs
With the two slabs and the gutter ready for assembly it is easier to decide where the actual place of use will be situated, in the house of near it. Now decided for composting of the excreta or for collecting them in a deep pit.
For building preparations for the construction of the composting cellars view the related chapter "Composting cabins". Such a double composting cellar is known from sanitation projects in Vietnam and India.
A drain has to be made for the water used in the bathroom, also containing the urine of its users. This spill water could also be collected as fertilizer. It contains essential agricultural nutricians. However prevent stink caused by open collection of urine.

If composting human excreta is not pracital or acceptable for the future users, the Bathroom/Toilet can be assembled over a deep pit. For the construction of the structure above the pit view the chapter "Temporary pit top construction".
Spil water from the Bathroom/Toilet can best be guided to a sink and not directly into the pit. This will reduce stink coming from the pit. Prevent the pit to be dug into groundwater for the same reason. Do not dig a pit close to a water well.
A neat separation has to be made around the slabs and gutter assembly. The entrance is best in the middle, above the gutter.
The opening in the slab for defecation can best be closed with a concrete block, such as also used in the procedure of casting the slabs, see picture.
Make sure future users get proper instruction how to use the toilet.
It is not clear how users should best be instructed of how to use the toilet. The following options are concidered:
Children are instructed at school (preferably the local school takes the lead with improving sanitation). At home it is the task of the mother to instruct and guide the children and female visitors. It is the task of the man at home to instruct male visitors. He should supervise the proper hygienic condition of the toilet. When the feces is to be composted, he should take care of changing from the use of the one container to thet other in time. If feces is not reused, he should plan in time to dig a new pit and plan the move of the bathroom-toilet unit to this new site.
In case the Bathroom-Toilet is used in the way as inspired by the "Twaalf Ambachten"(search for the page "Nonolet") put up this instruction leaflet.