Surface Area to Volume Ratio

Question

I know there are some aspects we can try to apply this surface area to volume ratio to say physical chemistry in order to see reactivity of chemicals. However I am very confused in my structural engineering elective course, it states that surface area to volume of high rise tower like structures is very important. I do see that the SA:V ratio of certain shapes in general give a very interesting and neatly simplified expression once computed, but I do not see what the application of SA:V ratio is when building structures of towers (Eiffel tower CN Tower etc...).

Can anyone help me explain the significance of SA:V ratio when building high rise structures (I would appreciate technical details as engineering is not my major of study i want to understand alittle better)?

Answer 1

In high rise design surface area to volume ratio is a significant factor in the amount of energy used to keep the building air conditioned and useable for its design function. The larger the surface the more heat transfers either from the building to outside in the winter or vice versa in the summer.

At the first glance it would seem a cube would have the least surface to volume ratio and be an ideal shape.

However a cube has a big portion of its usable floor are near its core, far away from the exterior windows which provide natural lighting and ventilation. So the core of the building needs continuous lighting and ventilation. which adds to the energy consumption.

The optimal building form factor and SA/V is one which would address all these concerns and find a balance between an energy efficient shell and energy needed for lighting and ventilation, etc.

• Location and angle of orientation of the building with respect to sun rays, wind direction and snow drift.

• The climate. Moderate Climate gives flexibility to have more surface to take advantage of natural light.

• The extreme conditions the building envelope will likely be exposed to.