Where the local housing authority have given notice of their satisfaction with proposals submitted to them under section 308 and are satisfied—
that it is necessary for the purpose of enabling re-development to be carried out in accordance with the proposals that a dwelling-house let on or subject to a protected tenancy or statutory tenancy (within the meaning of the Rent Act 1977) or let on or subject to an assured tenancy or assured agricultural occupancy should be vacated, and
that alternative accommodation complying with the requirements of this section is available for the tenant or will be available for him at a future date,
they may issue to the landlord a certificate, which shall be conclusive evidence for the purposes of section 98(1)(a) of the Rent Act 1977 or section 7 of the Housing Act 1988 (grounds for possession), that suitable alternative accommodation is available for the tenant or will be available for him by that future date.
The requirements with which the alternative accommodation must comply are—
that it must be a dwelling-house in which the tenant and his family can live without causing it to be overcrowded within the meaning of Part X;
that it must be certified by the local housing authority to be suitable to the needs of the tenant and his family as respects security of tenure, proximity to place of work and otherwise, and to be suitable in relation to his means; and
that if the dwelling-house belongs to the local housing authority it must be certified by them to be suitable to the needs of the tenant and his family as regards accommodation, for this purpose treating a dwelling-house containing two bedrooms as providing accommodation for four persons, a dwelling-house containing three bedrooms as providing accommodation for five persons and a dwelling-house containing four bedrooms as providing accommodation for seven persons.