In the Planning (Listed Buildings and Conservation Areas) Act 1990 after section 26G insert -
"Buildings in England: certificates of lawfulness
26H Certificate of lawfulness of proposed works
(1) A person who wishes to ascertain whether proposed works for the alteration or extension of a listed building in England would be lawful may make an application to the local planning authority specifying the building and describing the works.
(2) For the purposes of this section works would be lawful if they would not affect the character of the listed building as a building of special architectural or historic interest.
(3) If on an application under this section the local planning authority are provided with information satisfying them that the works described in the application would be lawful at the time of the application, they must issue a certificate to that effect; and in any other case they must refuse the application.
(4) A certificate under this section must -
(a) specify the buildin
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