Bats in the belfry, windows are jammed - London flat renting, deposits & landlords

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If the tenancy is a contractual periodic assured shorthold tenancy, the
landlord should follow any notice stipulations set out in the tenancy
agreement. The landlord may need to take legal advice before proceeding.
In the majority of cases in the private rented sector, a periodic tenancy will
be a “statutory periodic tenancy”, i.e. an assured shorthold tenancy that has
run on past its expiry date. In these cases, notices must be given in writing
and must:
• state that possession is required under section 21 of the
Housing Act 1988;
• have a notice period of at least two months; and
• expire on the last day of a period of the tenancy.
For example, if the rent period is from the 11th of the month to the 10th
of the next month, the end of tenancy date in the notice must be the 10th
of the month. If the tenancy is paid weekly the proper notice periods end
in the same way at the end of a period for which rent is paid. For example,
if the rent is paid every Monday for the period through to the following
Sunday, the notice must expire on a Sunday.