1. 8 1.89 refers to the usable area of the house where you live, that is, bedroom, living room, etc.

Second, 8.68 square meters, because you bought a flat, so-called sharing, the shared floor area of commercial housing mainly includes two aspects, one is elevator shaft, pipeline shaft, stairwell, garbage chute, power distribution room, equipment room, public hall, aisle, basement, guard on duty, and * * for the whole building.

Extended data

Do not calculate the building area range.

1. Components, fittings and artistic decorations that highlight the wall surface, such as columns, cribs, footholds, steps, pillar-free awnings, etc.

2. Outdoor ladders for maintenance and fire fighting.

3. The technical height is less than 2.2m..

4 structures, such as independent chimneys, flues, oil tanks, water towers, oil (water) storage tanks, silos, circular warehouses, underground civil air defense trunk lines, etc.

5. Operating platform, feeding platform inside and outside the building and platform for placing boxes and cans in the building space.

6. Roof water tank without enclosure structure. Overpass and platform, stage and backstage are hung with curtains and scenery.

7. Single-storey rooms such as operation room, control room and instrument room separated in a single-storey building.

8, height less than 2.2 meters deep foundation underground overhead layer, inclined building hanging scaffolding overhead layer.

References:

Baidu Encyclopedia: Calculation Rules of Building Area