10 things to know about Designing a Multi-storey Building

1. Most of the buildings in Indian cities have ground plus three floors. The recent trend is to construct buildings with at least 10–15 storeys so that the massive housing and commercial needs are satisfied.

2. Most of these buildings are made of reinforced concrete (RC). Mass of concrete floor slabs, beams, and columns of RC construction is higher than that of comparable steel construction.

3. This results in larger earthquake-induced bending moments and axial forces. As the height of building increases, the behavior of the structure becomes more complex.

4. Such buildings are more sensitive to wind and earthquake loads and hence, need to be very carefully designed and detailed.

5. The Wind influences the design of the structural system of tall buildings as well as their shape and form.

6. Since the day-lighting design has a large impact on the sustainability of the design, the facade may be one of the most important factors in controlling the daylight and shadow that enters a high-rise structure.

7. The latest trend is the use of double skin, and occasionally triple skin, facade with ventilation systems. Double glazing with argon-filled cavities, triple-glazing, and glass coating can increase U-values.

8. With careful design, high-rise structures can be aerodynamically designed to resist high wind speeds and to simultaneously utilize them, by using strategically placed wind turbines, thus producing more energy with no risk to the safety of the building’s users.

9. Multi-storey buildings are often analysed, designed, and detailed using a commercially available software. The commercial software packages available in the market include STAAD.Pro, SAP 2000, ETABS, SAFE, Nastran, Midas NFX, ANSYS, and STUDS. Many of these programs have analysis and design capabilities.

10. Linear analysis is considered sufficient for buildings having 15 storeys, whereas dynamic analysis is preferred for regular buildings in high seismic zones and having a height greater than 40 m, irregular buildings, and slender buildings subjected to heavy wind loads.

BONUS: AutoCAD is the most preferred detailing tool.