(1)References in this Part to adaptations in or in connection with a dwelling to avoid contraventions of section 20 (prohibition of smoke emissions from smoke control area) shall be read as references to the execution of any of the following works (whether in or outside the dwelling), that is to say—
(a)adapting or converting any fireplace;
(b)replacing any fireplace by another fireplace or by some other means of heating or cooking;
(c)altering any chimney which serves any fireplace;
(d)providing gas ignition, electric ignition or any other special means of ignition; or
(e)carrying out any operation incidental to any of the operations mentioned in paragraphs (a) to (d);
being works which are reasonably necessary in order to make what is in all the circumstances suitable provision for heating and cooking without contraventions of section 20.
(2)For the purposes of this section the provision of any igniting apparatus or appliance (whether fixed or not) operating by means of gas, electricity or other special means shall be treated as the execution of works.
(3)Except for the purposes of section 24 (power of local authority to require certain adaptations), works which make such suitable provision as is mentioned in subsection (1) shall not be treated as not being adaptations to avoid contraventions of section 20 of this Act by reason that they go beyond what is reasonably necessary for that purpose, but any expenditure incurred in executing them in excess of the expenditure which would have been reasonably incurred in doing what was reasonably necessary shall be left out of account.
(4)References in this section to a dwelling include references to any premises or part of any premises to which section 26 (grants towards certain adaptations in churches and other buildings) applies.