A: The Residential Tenancies Act provides in Section 13 that every tenancy agreement must be in writing and signed by both landlord and tenant. However, Section 13C also provides that an agreement which is not in writing shall be enforceable. In other words, a verbal tenancy agreement is also valid and enforceable. By default, if there has not been any written document, the conditons of the Residential Tenancies Act will apply. For the remainder conditions, which are not regulated in the Act (rent, duration, termination etc.), the party enforcing the contract would need to provide evidence for their relevant claims.