Water resistance Given the nature of the material, an adequate solution to protect the shelter from water and moisture should be considered as a priority in the design. The most exposed part of the shelter is the roof, that shall preferably have an inclination of 20 to 30째 to facilitate the drainage of rain water. A roof overhang would keep rain water off the walls and prevent the ingress of water at the junction. The overhang could vary between 15 and 30 cm, being limited due to wind loads. The flooring and wall basis in close contact with the ground has to be isolated from water. An elevated foundation or plinth can be used to raise the living area above the level of potential flood water. For this purpose sand bags can be a smart and cheap solution: the empty bag is lightweight and easy to fit in the shelter package, and it allows to fill it locally with available materials. For an additional protection a ground drainage is preferable.
Ventilation & thermal comfort As mentioned earlier the climate can vary heavily in emergency settlements around the world. Also people from different cultures will find different buildings comfortable, and be accustomed to different temperatures or humidities. In many settlements located in tropic areas overheating inside the shelter is a major problem and in some cases shading roof covers together with roof openings are used to create a proper ventilation (Axelsson, 2012). Ventilation gaps shall be designed with possibilities of high air exchange rate to avoid overheating, preferably by using draft and stack effect. Too keep thermal comfort during night the envelope shall be designed as airtight as possible, with possibility to close ventilation gaps. An elevated flooring is a good way to keep away from the moist ground and if closed can create a pillow of warm air. For even colder climates place for installing fireplace & chimney shall be prepared.
Vector control The term vector is used to define any organism or vermin that could carry diseases from one place to another. In case of a shelter two categories of animals should be considered: insects (fleas, mosquitoes, flies, etc.) and small animals (rats, birds, etc.).
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The design of the shelter should prevent the insects to enter: it should be possible to hang up mosquito nets on the windows, at least in the sleeping area, and holes within the material should be avoided if facing outdoor and not filled.
A man digging his own drainage in Lokossa camp, Togo. 50