House sharing is more than « several people in one home ». Legally, the way the lease is designed determines who owes what, what happens when one person leaves, and the landlord's room for manoeuvre. Two very different set-ups go by the same common name.
A single lease or separate leases
Two structures exist:
- the single lease, signed by all the housemates together for the whole dwelling. This is the most widespread arrangement. The housemates form a group facing the landlord.
- separate leases, where each occupant rents their room under a distinct contract, with the common areas shared. The landlord then has an individual relationship with each of them.
The choice changes everything: responsibilities, handling of departures, calculation of guarantees. Under a single lease, Wallonia and the Brussels Region also require a sharing pact (pacte de colocation), a written agreement between housemates that governs communal life (splitting of rent and charges, guarantee, maintenance, departure).
The joint-liability clause
This is the point with the heaviest consequences. Under a single lease with a joint-liability clause, each housemate is liable for the entire rent, not just their share. If one fails to pay or disappears, the landlord can claim the whole amount from the others. Joint liability protects the landlord; for the housemates, it turns the choice of a co-occupant into a shared financial risk.
The sharing pact makes it possible to organise the split internally, but it does not bind the landlord: towards him, joint liability prevails as long as it is provided for in the lease.
The departure of a housemate
What happens when one person wants to leave before the others? The regional regimes organise a notice period for the departing housemate and, often, a logic of replacement: the person leaving may be required to propose a replacement, and their full release depends on the agreement of the other housemates and the landlord. Without anticipation, a poorly framed departure leaves the person committed for longer than they think.
The rental guarantee follows the same group logic: setting it up and returning it are handled collectively, something the pact has every interest in detailing.
Three Regions, three regimes
The residential lease is a regional competence: Wallonia, the Brussels Region and Flanders each have their own framework for house sharing, with differences on the pact, joint liability and departures. Before signing, check the regime of the Region of the dwelling with the corresponding official source - it is that regime that applies, regardless of where the housemates reside.