Penthouse
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.
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:
- 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.
- Fireplaces.
- 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.
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
Featured articles and news
Plumbing and heating for sustainability in new properties
Technical Engineer runs through changes in regulations, innovations in materials, and product systems.
Awareness of the Carbon Border Adjustment Mechanism
What CBAM is and what to do about it.
The new towns and strategic environmental assessments
12 locations of the New Towns Taskforce reduced to 7 within the new towns draft programme and open consultation.
Buildings that changed the future of architecture. Book review.
The Sustainability Pathfinder© Handbook
Built environment agency launches free Pathfinder© tool to help businesses progress sustainability strategies.
Government outcome to the late payment consultation, ECA reacts.
IHBC 2025 Gus Astley Student Award winners
Work on the role of hewing in UK historic conservation a win for Jack Parker of Oxford Brookes University.
Future Homes Building Standards and plug-in solar
Parts F and L amendments, the availability of solar panels and industry responses.
How later living housing can help solve the housing crisis
Unlocking homes, unlocking lives.
Preparing safety case reports for HRBs under the BSA
A new practical guide to preparing structural inputs for safety cases and safety case reports published by IStructE.
Male construction workers and prostate cancer
CIOB and Prostate Cancer UK encourage awareness of prostate cancer risks, and what to do about it.
The changed R&D tax landscape for Architects
Specialist gives a recap on tax changes for Research and Development, via the ACA newsletter.
Structured product data as a competitive advantage
NBS explain why accessible product data that works across digital systems is key.
Welsh retrofit workforce assessment
Welsh Government report confirms Wales faces major electrical skills shortage, warns ECA.
A now architectural practice looks back at its concept project for a sustainable oceanic settlement 25 years on.
Copyright and Artificial Intelligence
Government report and back track on copyright opt out for AI training but no clear preferred alternative as yet.
Embedding AI tools into architectural education
Beyond the render: LMU share how student led research is shaping the future of visualisation workflows.
Why document control still fails UK construction projects
A Chartered Quantity Surveyor explains what needs to change and how.
Inspiration for a new 2026 wave of Irish construction professionals.
New planning reforms and Warm Homes Bill
Take centre stage at UK Construction Week London.


























