An architect's house in the heart of Paris

Flat roof terrace

Flat roofs may be used for purposes other than those traditionally associated with a roof. If properly designed, they can help create more space and facilitate outdoor living. Transforming a roof into a terrace can be an effective solution for those who live in city centres, where it is not always possible to increase the space and where outside areas, such as balconies, are often not available.

Converting a roof into a habitable terrace is an option often considered also in more modern commercial buildings. The absence of outside space in high-rise structures could be addressed by converting flat roofs into recreational areas. In some situations, it is worth considering whether, in addition to a terrace, a garden or sports area can be created to enjoy during work breaks.

In the event it is decided to convert an existing roof, the administrative and procedural aspects related to converting the total volume of the building must be considered. Additionally, if the roof terrace is installed in replacement of a pitched roof, a static test must be performed for the purposes of understanding the static condition of the building. This will detect any changes in the gravitational load and the foundations and will check the building's seismic resistance.

Other decisive factors to consider when choosing a terraced roofing system is the presence or otherwise of inhabited spaces underneath the roof, which will inform decisions regarding insulation and waterproofing and the choice between warm roof and inverted roof solutions. The choice of warm roof or inverted roof defines the composition of the roofing system both with regard to its components and the sequence in which they are installed.

To complete the design of the roof terrace, a decision must be made regarding which type of parapet and flooring to install. Apart from the aesthetic aspect, both of these elements affect the security and durability of the roof.