A notice in relation to which it is declared by any provision of this Act that this section applies shall indicate the nature of the works to be executed and state the time within which they are to be executed.
Subject to any right of appeal conferred by section 102 below, if the person required by such a notice to execute works fails to execute them within the time limited by the notice—
the local authority or the regulator (as the case may be) may themselves execute the works and recover from that person the expenses reasonably incurred by them in doing so, and
without prejudice to that power, he is liable on summary conviction to a fine not exceeding level 4 on the standard scale and to a further fine not exceeding £2 for each day on which the default continues after he is convicted.
This section has effect subject to any modification specified in the provision under which the notice is given.