Some Salas are more complex looking because of two projecting additions from the long sides of their rectangular plan, forming in this way a cross plan. ln general, this kind of Salas has no pyramidal superstructure, but in some cases, for example the Salas at the Royal summer residence of Bang Pa-In. do have the universal pyramidal roofs.
Salas have always been built also for civil purpose,for example along roads or canals where people pass and like the chance to rest for a while. Nowadays small simple Salas, stand along major highways and serve as bus stops.
In the old day, Thai Pavilion function for many activities but in present time it is more like representative of Thai architecture. Basically, Thai pavilion serves as a shelter to give shade from sun and rain for public use. The construction is similar to Thai houses but an obvious difference is that Thai Pavilion does not consist of wall, only columns with open space.