§ 5-2 The Ministry responds to enquiry on degree of utilisation and protruding building elements

We refer to your e-mail of 31.01.2019. In your enquiry you request our assistance with questions relating to protruding building elements and degree of utilisation. You ask whether a first floor (2. etasje) that overhangs the ground floor (1. etasje) is considered as a protruding building element ("utstikkende bygningsdel"), and if so, whether the overhang would need to be included in the built-up area (BYA, "bebygd areal") calculation, particularly if the height above the terrain is greater than 5,0 m above the terrain.

The Ministry of Local Government and Modernisation is the supreme building authority in accordance with the Planning and Building Act . We provide general guidance and interpretation on how to understand the Act and its appurtenant provisions. We are unable to provide guidance in specific building cases, unless the case is the subject of an appeal to the Ministry. Thus, the following interpretation is only intended to provide general guidance on the understanding of the Act.

The Ministry's assessment

Smaller building elements that overhang the ground floor by less than 1,0 m and are situated lower than 5,0 m above the terrain are not included in the BYA calculation. The overhang of an entire floor is not considered as a portruding building element ("utstikkende bygningsdel").

Further guidance on the relevant rules and regulations concerning built-up area (BYA):

We refer to the regulations on technical requirements for construction works (TEK17, "byggteknisk forskrift") section 5-2 and the guidelines in "Grad av utnytting – Beregnings- og måleregler" (H-2300), page 19, on how to calculate built-up area and portruding building elements. 

TEK17 section 5-2 provides:

"Built-up area is calculated on the basis of Norwegian Standard NS 3940:2012 Area and volume calculations for buildings, though such that parking areas are included in the basis for calculation in accordance with section 5-7. A building plot's built-up area shall be stated in m2 BYA and given in whole numbers."

In the guidelines "Grad av utnytting" (H-2300), built-up area (BYA) is specified as the area in square meters that buildings, overbuilt open areas, and constructions above the ground occupy in the terrain, see figure 2-3 and 2-4 on page 21.

BYA of a plot of land is the sum of the built-up area of all buildings, building parts (1) and constructions above the ground, overbuilt open areas and the necessary areas for parking space on the plot.

BYA of a building is the area that the building occupies in the terrain, including building parts outside of the façade line that impact upon the use of the underlying terrain. Gutters et cetera are not included. To calculcate BYA, measurements are taken from the outside of the outer wall. If the building has a base that extends outside the façade line of the building, the
measurements are taken from the outer edge of the base. Building elements outside the façade line are measued from the outer edge of the construction. These elements include terraces, balconies, staircases, and roof superstructures.

Portruding building elements with a free height above the terrain less than 5,0 m shall be included in the calcualtion of the built-up area. The intention is to ensure that portruding elements that significantly affects the usability of the underlying terrain is included in the calculation. Portruding elements up to 1,0 m from the façade line, on the other hand, shall not be included in the calculation.

Attached is also the document in Norwegian translation (see link on this page). 


Direktoratet for byggkvalitet

(1) Physical part of a building or other structure (usually composed of several product elements), e.g. outer walls, inner walls, surfacing, pillars, beams, cladding and outer roof (SINTEF Byggforsk definition, our translation).