the same laws of physics, and hence will demonstrate significant similarities in structural forms. Climate One of the most significant influences on vernacular architecture is the macro climate of the area in which the building is constructed. Buildings in cold climates invariably have high thermal mass or significant amounts of insulation. They are usually sealed in order to prevent heat loss, and openings such as windows tend to be small or even absent altogether. Buildings in warm climates, by contrast, tend to be constructed of lighter materials and to allow significant cross-ventilation through openings in the fabric of the building. Buildings for a continental climate must be able to cope with significant variations in temperature, and may even be altered by their occupants according to the seasons. In hot arid and semi-arid regions, vernacular structures typically include a number of distinctive elements to provide for ventilation and temperature control. Across the middle-east, these elements included such design features as courtyard gardens with water features, screen walls, reflected light, mashrabiya (the distinctive oriel window with timber lattice-work) and bad girs (wind-catchers). Buildings take different forms depending on precipitation levels in the region – leading to dwellings on stilts in many regions with frequent flooding or rainy monsoon seasons. For example, the Queenslander is an elevated weatherboard house with a sloped, tin roof that evolved in the early 19th-century as a solution to the annual flooding caused by monsoonal rain in Australia's northern states. Flat roofs are rare in areas with high levels of precipitation. Similarly, areas with high winds will lead to specialised buildings able to cope with them, and buildings tend to present minimal surface area to prevailing winds and are often situated low on the landscape to minimise potential storm damage. Climatic influences on vernacular architecture are substantial and can be extremely complex. Mediterranean vernacular, and that of much of the Middle East, often includes a courtyard with a fountain or pond; air cooled by water mist and evaporation is drawn through the building by the natural ventilation set up by the building form. Similarly, Northern African vernacular often has very high thermal mass and small windows to keep the occupants cool, and in many cases also includes chimneys, not for fires but to draw air through the internal spaces. Such specializations are not designed, but learned by trial and error over generations of building construction, often existing long