Re-opened in 2005, the National Library Building is one of the first structures in Singapore to have its composite steel structure designed using performance-based fire engineering. The building uses heavy shading on its façade to reduce solar heat to improve the comfort of the readers as well as to protect the book collection. To prevent direct sunlight from entering the library, Arup developed sunshades to give a 30 degree solar cut-off shading into the façade. In addition, analysis has been carried out on the window height and shade spacing to optimise the efficiency of the sunshades.

Double-glazed windows have been used on the façade of the building to save energy by containing the air-conditioning within the premises of the building. In addition to the energy-conserving windows, carpets and wooden fixtures have been made out of recycled and sustainable forested local timber to add to the environment-friendly element of the building. The building has been fitted with light sensors that dim the lights according to the intensity of natural sunlight entering the building. Motion sensors activate the escalators when it is required and rain sensors shut of sprinklers when water supply is abundant.