The first concept of nowadays toilets
The medieval toilet was called latrine but also privy or garderobe as a euphemism. Other names included: ‘privy chamber’ or just ‘privy’, but also draught, gong, siege-house, necessarium, and even golden tower. The term garderobe later came to mean wardrobe in French and its original meaning was because of space which in castle toilets was never bigger than necessary. The medieval toilet was basically primitive, except for castles where one might find a little more comfort than elsewhere but also more privacy and efficient waste disposal. Castle toilets are still easily identifiable because they protrude from exterior walls.
Toilets were usually built into the walls so that they projected out on corbels and any waste could fall below into the castle moat. Sometimes, waste went directly into a river, and some castles, instead, had latrine shafts emptying directly in the courtyard or bailey while still others hung conveniently over a cliff face.
The protruding shaft of masonry that made up the toilet was sustained from below or might nestle in the junction between a tower and wall. Some waste shafts were short while others reached almost to the ground. In the latter case, that might prove a dangerous design feature if there were a siege of the castle.
Another design was to have tiers of toilets on the outside wall where the shafts sent waste to the same collection point. There were also toilets in ground floor buildings and these had stone drainage channels to drain away waste. Waste from such collection points, or from the ditch in general, was likely collected by local farmers to be reused as fertilizer. When castles became larger and more comfortable from the 14th century C.E., the number of conveniences increased accordingly.
From the interior, the toilet was set back in a recess or within a mural chamber. A short narrow passageway sometimes led to a toilet, often with a right-angle turn for greater privacy. Pairs of toilets, separated by a wall, were not uncommon and these might share the same waste chute. The chamber of the castle’s lord and the castle’s priest often had a private latrine including a chamber pot if needed which was an accessory everyone had.
The toilet seat was made of a wooden bench covering the shaft hole in the masonry. The wood was usually cut with a rectangular or keyhole aperture. Hay, grass, or even moss were used as toilet paper. However, these toilets were also a dangerous place because hay might catch fire or people might fall into the shaft.
In addition, some toilets had a window to let in the fresh air, which for the same reason was not shuttered like other windows of a castle. The floor might have been scattered with rushes and aromatic herbs and flowers to deter vermin and offer a more pleasant fragrance. Walls were sometimes whitewashed with a coating of lime-plaster which maximized the light coming from the small window as well as killing off bacteria.
The toilet was cleaned either by a simple bucket of water thrown down the shaft or by diverting the wastewater from the kitchen sinks. More rarely, rainwater was diverted from gutters above the latrine which might also be collected into a cistern and then periodically opened to flush the toilet shaft. Because of the stink, it wasn’t uncommon to hang clothing near latrines since ammonia fumes helped to kill mites.
Lastly, there also were urinals. They were triangular holes built into some tower walls so that defenders did not have to leave their post for very long.
Apparently, the concept of privacy and discretion came right from the noble toilets while common people used to use toilets in groups without problems, indeed, it was also an opportunity for sociability.
Source ancient.eu
