This section applies where a person (the "improving tenant") who is or was the secure tenant of a dwelling-house has lawfully made an improvement and has borne the whole or part of its cost; and for the purposes of this section a person shall be treated as having borne any cost which he would have borne but for a renovation grant or common parts grant under Chapter I of Part I of the Housing Grants, Construction and Regeneration Act 1996 (grants for renewal of private sector housing).
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In determining, at any time whilst the improving tenant or his qualifying successor is a secure tenant of the dwelling-house, whether or to what extent to increase the rent, the landlord shall treat the improvement as justifying only such part of an increase which would otherwise be attributable to the improvement as corresponds to the part of the cost which was not borne by the tenant (and accordingly as not justifying an increase if he bore the whole cost).
The following are qualifying successors of an improving tenant—
This section does not apply to an increase of rent attributable to rates or to council tax.