Traditional homes in Iranian desert towns are usually built around a central courtyard with windows, doors, arches and other architectural features facing in, rather than out.
Traditionally, activities in the house change location with the seasons.
In winter, the family would gather in the south-facing side of the house which has larger windows to make the best of the winter light. Then in summer, more activities would take place in the north-facing side where the windows were smaller.
Height and depth are also put to good use. On a flat, open desert plain, the only place to escape from the sun is to go underground and so traditional Kashani houses are typically built on four levels, two of which are below ground. On both sides of the courtyard steep steps lead down to a sardab which is kept cool by permanent shade and fresh breezes wafting through vents in the walls. The difference in temperature is just as if you had walked into an air-conditioned room.
One level deeper still is the kande (dug-out) which is a small chamber cut from the very earthen foundations of the house. This room makes the perfect natural refrigerator.
By taking the trouble to harness wind and water the architects of Kashan built air-conditioning systems without the benefit of electricity and plumbing without the aid of pipes. Sadly, these days, with the perceived benefits of technology, little importance is given to the old, organic ways. Take a walk along the rooftops of the bazaar and you'll see many old houses that are rapidly returning to the dust from which they came.
A small number of traditional Kashani houses have been restored and opened so that the public can see their ingenuity. After visiting them you wonder why the whole city can't return to the elegance of the old ways.