We all know that buildings don't always turn out like the renderings. Last-minute changes and real-life materials can all cause discrepancies between the vision and reality of a project. In our weekly Flash Forward Friday feature, we take a look at how different projects stack up.

Dubai boasts more than a few tall buildings and towers on its roster, but the crown jewel of the city is its megatall skyscraper, the Burj Khalifa. Previously known as Burj Dubai, the Burj Khalifa stands at 830 metres, making it the tallest standing structure in the world.

Burj Khalifa rendering, image via Emaar Properties

Plans for this building began when the government of Dubai expressed an interest in shifting from an oil-based economy to a tourism-based one. Wanting to put Dubai on the map to garner more international interest and investment, the idea for a mega-tall building like the Burj Khalifa was born. Developed by government-backed Emaar Properties, it was designed as the centrepiece of a large mixed-use development which included three hectares of parkland, the Dubai Mall, nine hotels, and the 30-hectare man-made Burj Khalifa Lake.

Burj Khalifa completed, image by Flickr user Nicolas Lannuzel via Creative Commons

The Burj Khalifa stayed generally true to its renderings, although the final glazing appears more varied and the initial uniform setbacks within the bundled tube design have been staggered. The design of the building was partially inspired by a spiral minaret, which is a historically Islamic pattern in which the building grows more slender as it grows higher. When seen in plan, the structure has a three-armed Y-shape, which increases interior natural light while maximizing views. As the building grew higher during construction, a series of setbacks decreased the sizes of each ascending arm, allowing for lateral support.

We will return next Friday with another comparison!