What is common area and how is it split between tenants?
Common area is the part of a building that no tenant rents exclusively — lobbies, hallways, stairwells, elevators, cafeterias, parking garages, and other shared spaces. On the platform, common area is defined on the building record as:
Common Area = Total Area − Rentable Area
When you create a building, you set total_area (the full building footprint) and rentable_area (the sum of all spaces you can lease out). The difference is your common area.
How common area costs are allocated
The standard method — and what most landlords use — is proportional to rented area. Each tenant pays a share of common area costs equal to their rented area as a fraction of the total rented area in the building.
Example
- Building rentable area: 1,000 m²
- Tenant A rents 800 m² (80%)
- Tenant B rents 200 m² (20%)
- Monthly common area costs (cleaning, elevator, lighting): €2,000
- Tenant A pays: 80% × €2,000 = €1,600
- Tenant B pays: 20% × €2,000 = €400
This is the default behavior when you enable "Auto-distribute common area" on the building. The system creates a "Common Areas" cost type in your allocation matrix and automatically calculates each tenant's percentage based on their rented locals.
The only moving part is the tenant. Buildings and locals are relatively static — once you set up the building's locals (units), they rarely change. What changes is which tenants occupy which locals and how much area each tenant rents. When a tenant moves in or out, the allocation percentages automatically recalculate.
Where to see this: Cost Allocation → select your building. The metrics section shows total area, rentable area, and common area. The allocation matrix shows each tenant's percentage per cost type.