[BIFE ENG ver.] History of the facade 4/4

Eiffel Tower, Paris, 1889

The appearance of curtain wall buildings shares the context with the mass production of steel in the 19th century. Since then, steel has rapidly emerged as a new building material. For example. the Eiffel Tower (1889) is a famous building made during this period. Opposition to the Eiffel Tower in the early days was tremendous; however, it is now a symbol of testing the possibility of new building material - steel, and representing the era of this material.

 

High-rise building made of stone is too heavy

Steel is about eight times stronger than stones but weighs much lighter. Therefore, the building's load could be effectively tolerated with much less material, as a result, the weight of the building could be much lighter. The reason why the high-rise building could not be built during the time of stone construction was because of the weight of the building itself. To bear their own weight of the stone, the walls had to be extremely thick in the bottom part. This makes the use of land very inefficient. No building owner wants half of the land to be filled only with walls.

 

Steel column and steel structure high-rise buildings

There are structural problems as well as efficiency of land use. At this point, the ground that finally supports the weight of the building can sink as the weight of the building exceeds the structural capacity of the ground. However, with the advent of steel, people were able to weave steel or build steel columns to build high-rise buildings. Now, rather than a thick wall structure, a steel column-beam building has become a trend.

 

The structural characteristic of curtain walls

After building such a tall building, how can we cover it? This is the background of the curtain wall, the concept of covering the building in the most effective and light way. The curtain wall is derived from the meaning that the outer skin of the building wraps around the building like a curtain. In the cross-section diagram above, the facade (blue line) is suspended from the architectural structure(slab). The load on the curtain wall is not digested inside the curtain wall but is transferred to the architectural structure. It's like a curtain hanging from the structure of a building. Therefore, all curtain wall buildings have support from the architectural structure - columns, beams, slabs, etc. - to fix the facade.

 

Facade as a non-structural element

The structural characteristics of the curtain wall allow physical adventure because it does not digest any load within itself. In fact, the unique design of the architect is boldly revealed in the relatively unrestricted facade area.

 

However, at the same time, reducing the weight of the building and using mass-produced materials will be necessary to create efficient, inexpensive facades. This need created many curtain wall materials on the market. Typical examples are stone panels, aluminium panels, steel panels or glass panels. The buildings with glass facades that we commonly see as we pass through the streets are glass curtain wall buildings.