Building add-on

The part of the building that delivers relevant services necessary for the tenants’ and the entire building’s operations. Add-on of a building comprises the following areas: primary and secondary lobbies, corridors, including exit corridors, plant rooms and utility rooms, toilets for the whole building, and service rooms. According to the applied standard, various types of […]


This concept is commonly used to determine leasable areas in commercial buildings. GLA consists of tenants’ net floor areas (for their exclusive use) as well as add-on used by different tenants. Add-on is distributed pro rata among all tenants through the application of add-on factor.