Areas
These are floor areas according to DIN 277 (usable area, service area, circulation area, net floor area, construction area, gross floor area) as well as areas of building components (foundation, exterior walls, interior walls, ceilings, roof, other).
Building age
The building age is defined as the year in which a building was constructed. In data on the construction sector provided by Germany’s Federal Statistical Office, domestic buildings are classified by building age. The age classes applied here are practically the same as those established by the Statistical Office to analyse the stock of domestic buildings.
Built area
The built area is the portion of the plot area that is built over or covered by a structure above the ground surface or underbuilt below the ground surface (DIN 277:2021-08).
The built area corresponds to to the gross area of the ground floor or the so-called building floor area and is frequently termed the building footprint.
Circulation area
The circulation area is the portion of the net floor area that serves the horizontal and vertical traffic circulation of the building (DIN 277:2021-08).
Construction area
The construction area is the portion of the gross floor area that includes the floor areas of the rising building structures of the building (DIN 277:2021-08).
Construction volume (CV)
The construction volume is the portion of the gross volume that comprises the volume of the building's structures (DIN 277:2021-08).
DIN 277
The different areas and volumes determined here are based on DIN 277:2021-08 “Areas and volumes in building construction”. It has been in force since August 2021 and regulates the division of the areas of a building. Accordingly, the gross floor area (GFA) of a building is made up of the net room area and the construction floor area, whereby the net room area includes the usable area, the technical area and the traffic area (DIN 277:2021-08).
The definitions of the individual areas and volumes (gross floor area, net room area, construction floor area, usable area, technical area, circulation area, gross volume) are each listed separately.
Gross floor area (GFA)
The gross floor area GFA is the total area of all floors or or a section of a building. The gross floor area is made up of the net floor area and the construction area (DIN 277:2021-08).
Gross volume
The gross volume is the total volume of a building or storey. It includes the net volume and the construction volume (DIN 277:2021-08).
Net volume
The net volume is the portion of the gross floor area that comprises the volume above the net floor area (DIN 277:2021-08).
Net floor area (NFA)
The net floor area is the portion of the gross floor area that includes the usable area, the technical area and the circulation area (DIN 277:2021-08).
Material
Materials are determined individually and specified in aggregate form for building components and material groups as well as total masses. The table on building materials classifies the individual materials to material groups.
Representative building
A representative building (whether a real or invented building) is a typical example of a building group (here age classes). It presents all characteristic features of these groups. Synthetic building These are derived from diverse numbers of real domestic buildings – so-called representative buildings – and reflect the average building and dwelling sizes, the structural designs as well as the employed materials in each respective building period.
Service area
Service areas are those areas where a building’s technical equipment is housed. According to DIN 277-2: 2005-02, Table 1, No. 8, these are areas dedicated to heating and hot water production, the supply of electricity or telecommunications.
Synthetic building
These are derived from diverse numbers of real domestic buildings – so-called representative buildings – and reflect the average building and dwelling sizes, the structural designs as well as the employed materials in each respective building period.
Usable area (UA)
The usable area is the portion of the net floor area that serves the purpose of the building (DIN 277:2021-08).
Depending on the purpose, seven different uses are distinguished: UA 1 - Living and residence, UA 2 - Office work, UA 3 - Production, manual and machine work, research and development, UA 4 - Storage, distribution and sales, UA 5 - Education, teaching and culture, UA 6 - Healing and care, UA 7 - Other uses (e.g. storage rooms, bicycle rooms, sanitary rooms, changing rooms, etc.) (DIN 277:2021-08). Uses UA 1 to UA 6 reflect the main use of a building (the predominant purpose of use). UA 7 describes other uses that are also present in the building in addition to the main use. In DIN 277 versions prior to 2016, they were summarized under the term “residual usable areas” (Nebennutzfläche).
For residential buildings, the usable area is usually made up of UA 1 and UA 7; for non-residential buildings, it is usually made up of UA 2, UA 3, UA 4, UA 5 and/or UA 6 and UA 7.
Volume
This is the gross interior volume of a building according to DIN 277:2021-08.