Last edited 20 Oct 2020



The term 'penthouse' is used to describe an apartment on the top floor of a high-rise building. According to the New York City building code, a penthouse is ‘ enclosed structure on or above the roof of any part of a building, which is designed or used for human occupancy.’ Penthouses are frequently the largest, most luxurious, and therefore the most expensive, apartments in a building.

In architectural terms, a penthouse is a single-occupancy living space built onto the rooftop as an additional floor, set back from the outer walls. These setbacks act as terraces and allow for significantly larger open spaces than cantilevered balconies. Some penthouses may have two or more levels. These might be referred to as a 'duplex', 'triplex' and so on.

Penthouse apartments became popular in New York during the ‘Roaring Twenties', as economic growth created many of the first skyscraper developments. Wealthy Americans equated luxury and prestige with having the best view from a building, and so favoured the top floor apartments.

Penthouses are also characterised by their luxurious amenities which are often not included in the rest of the building’s apartments. Such features might include:

In recent years, the term acquired a broader definition as developers seek to make the most out of their new construction projects. Sometimes the term ‘penthouse’ is used to refer to apartments on one of the uppermost floors of a high-rise building rather than being on the top floor. Buildings can be designed with setbacks on multiple top floors, in an attempt to create more apartments with terrace views that can be promoted as ‘penthouse apartments’. These are sometimes referred to as 'sub-penthouses' and have a lower level of specification than the actual penthouses.

High-rise buildings may also have 'mechanical penthouses' which are structures on the roof deck that enclose mechanisms such as lift equipment and rope descent systems (RDS) for window cleaning.

[edit] Find out more

[edit] Related articles on Designing Buildings Wiki

Designing Buildings Anywhere

Get the Firefox add-on to access 20,000 definitions direct from any website

Find out more Accept cookies and
don't show me this again