My daughter is currently living in Edinburgh and her tenancy agreement is about to expire in early February. Her landlord has told her there is no need to sign a new one because if nobody issues a notice, then the old one just extends itself automatically
Forgive my ignorance but I've never heard of this happening before 
Is it true that the tendency would renew itself and there would be no need to sign a new one? Is any additional documentation required? Also, does the tenancy renew itself for the same period as the original one (ie; one year) or on a rolling basis?