How do I know if my contract is Joint and Severally Liable?

Whether you are liable for the rent of your housemates depends on whether your contract is for a joint tenancy or single tenancy. If you and the other tenants are all signing the same contract, then you are ‘jointly and severally’ liable – this is a joint tenancy.
   
If you have a guarantor for this type of contract, their agreement also comes under the joint and several liability, so they would also be liable for the entire rent of the whole house.