- Project plans
- Project activities
- Legislation and standards
- Industry context
Last edited 30 Apr 2017
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 ‘...an 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.
- A private entrance or lift (without which, it is sometimes argued that the apartment does not in fact qualify as a true penthouse).
- Higher/vaulted ceilings.
- A large floor area.
- Larger windows.
- A swimming pool and jacuzzi.
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.
 Find out more
 Related articles on Designing Buildings Wiki
Featured articles and news
Reminding us what is possible.
Five signs you are at risk.
Biotechnology as it applies to the built environment.
Stopping sound coming through windows.
Government response to the Building a Safer Future consultation.
Energy savings quickly payback any small additional capital investment.
Overbuild and air-space developments.
Airports National Policy Statement and its impact on infrastructure.
Organisations will collaborate on infrastructure initiatives.
Technology informs procurement and planning practices.
BSRIA releases market sector growth projections.