Paragraph 1

The carrying out of any of the following works, that is to say—

(a)

the rebuilding, as often as occasion may require, of any building which was in existence on the appointed day, or of any -building which was in existence before that day but was destroyed or demolished after the seventh day of January, nineteen hundred and thirty-seven, including the making good of war damage sustained by any such building ;

(b)

the rebuilding, as often as occasion may require, of any building erected after the appointed day which was in existence at a material date ;

(c)

the carrying out of works for the maintenance, improvement or other alteration of any building, being works which affect only the interior of the building or which do not materially affeot the external appearance of the building and (in either case) are works for making good war damage,

so long as (in the case of works falling within any of the preceding sub-paragraphs) the cubic content of the original building is not exceeded—

(i)

in the case of a dwellinghouse, by more than one-tenth or seventeen hundred and fifty cubic feet, whichever is the greater, and

(ii)

in any other case, by more than one-tenth.