History of Permapreta®

Permapreta® is the result of 25 years of research and prototypes developed, tested, and studied in the bathrooms of different Permaculture projects run by the UIP (International University of Permaculture), including the Gaia Ecoaldea, in the province of Navarro, Argentina, as well as in different parts of the world.

After studying the double chamber and compost models, it was analysed and investigated, looking for a new dry toilet model to avoid the problems that these caused.

Currently, Permapreta® is manufactured in Spain from where it is exported all over the world.

What ideas move Permapreta®

There are 2.4 billion people in the world who do not have access to a decent bathroom and who are forced to use unhygienic, dangerous and polluting systems. Water pollution is one of the biggest triggers of diseases. For instance, infant diarrhoea causes 1,800,000 deaths per year.

At Permapreta®, we believe that decent and safe bathrooms are a right of every human being and must be accessible to all people, regardless of social class. For this reason, our project proposes a socially acceptable system, easily accessible, economic, and beneficial for nature.

Permapreta® System


Permapreta® dry toilet and compost systems offer innovation in the transformation of waste. This system is based on the keeping of a bed of worms (E. foetida). It is a continuous flow

vertical management method. This was developed for the optimal functioning of the bathroom with an efficient ventilation system, which also includes: a double system of grids for the separation of the layers of substrate and humus and perfect aeration, to which we add a periodic contribution of pyrolytic carbon, microorganism culture, and we also take into account humidity correction factors and levelling of the carbon/nitrogen ratio.

Why choose Permapreta®


Quick and easy installation. Can be incorporated into the construction of houses, buildings, etc. Permapreta® is the first composter and dry toilet system with a patented humus discharge system through the upper part of the chamber.


The volume and work of emptying are reduced considerably if it is compared with other systems. For example, an average family that generates 1200 kg of faecal matter, paper and aggregate, in a year the amount to be processed would result in only 8 kg of humus with the Permapreta® system.


Dry toilets usually require the cooperation and work of users to avoid odours. It is difficult to achieve sometimes. Permapreta® has a ventilation system that eliminates this problem.


Due to its materials, design and ease of installation, this system is one of the most economical waste management infrastructures on the market, as well as guaranteeing first-class technical quality.


Permapreta® requires minimal maintenance, without the need to add materials such as lime, ash or sawdust, commonly used in the maintenance of traditional dry toilets.

Safety against pathogen

Due to Permapreta® own characteristics of the continuous flow worm humus, the faecal wastes into pathogen-free organic matter. This matter is safer than that obtained from double chamber or single chamber dry toilet.

Free of animals

Permapreta®, being a compact and hermetic system, makes the intrusion of insects and rodents impossible.


Permapreta® can be installed at ground level, and so it is fully compatible with accessible bathrooms for people with reduced mobility.

Projects that have choosen Permapreta®

IACC - Barcelona

In 2019 we collaborated with the Institute of Advanced Architecture of Catalonia (IAAC) to develope an EcoHouse for the final Master project (Master In Advanced Ecological Buildings) at Valldaura Labs. There we met with the architect students of the project, who came from different parts of the world. We help them to assemble the bathroom and photovoltaic system of this ecological and self-sustainable Tiny House

Biosur Insectarios

Another project that has opted for Permapreta® in its waste management is Biosur Insectarios, where a Permapreta® dry toilet complete with urinal and sink has been installed for the use of its workers.

ARQUITERIA – okambuva

The Okambuva training centre (Coop. Bioconstrucción) opted for a Permapreta® dry toilet to place it where training cycles in bio construction are carried out. Besides being used as a toilet, it is a sample of efficient and sustainable waste management methods for green buildings.

Find Us:

Polígono el Pont.
Avenida España nave 32

Call Us:

(+34) 629034278
(Jose Vicente)

(+34) 642330223

Mail Us:


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