Weather resistance is a material's ability to hold up against deterioration from exposure to harsh elements. This may include strong sun, wind, rain, humidity, snow or extremely hot and cold temperatures. Manufacturers of materials for homes, cars and even clothing may incorporate the idea of weather resistance into their products. For example, the paint finishes of automobiles are often made to prevent rusting by being resistant to the cumulative effects of water, sun and salt.
Some climates are harsher than others and present unique challenges. Homes may need to be built according to certain building codes that make it less likely for structures to sustain damage due to high winds or cold winters. For example, siding materials may provide protection against repeated exposure to wind by containing stronger, more durable material. The material may also be more able to withstand colder temperatures than other forms of siding.
Material with weather resistance may be manufactured to endure several different elements. In some areas there is the problem not only of high temperatures, but also high humidity. This type of climate can lead to problems with mold development and deterioration, which can cause severe damage to a building's structure.
Often the weather resistance of manufactured materials will be tested according to a ratings system. The degree of weather resistance to certain elements is determined by simulating exposure to adverse weather elements such as water, high temperatures, a salty atmosphere, and solar radiation. If a material has a very strong ability to withstand exposure, it will most likely be given one of the highest ratings. The inability to endure exposure will most likely result in a low rating or a rating that indicates the material is not weather resistant.
Although a material may be determined to be weather resistant, this does not mean that it will not incur any damage. Given enough time, even the most highly rated material will eventually wear out. Examples of this can be seen on the exterior of cars that are older than ten years. Manufacturers of weather resistant materials will usually give a time range for expected performance, such as a ten year rust free guarantee.
Clothing manufacturers also incorporate the idea of weather resistance. Certain materials are effective at blocking out repeated exposure to rain and cold. The material is almost pore less in the sense that it does not absorb water, but rather repels it. This prevents the material from becoming wet on the interior. Some coats that are used by outdoor enthusiasts contain this type of material.