Environmental Planning and Assessment Regulation 2000
136H Condition relating to shoring and adequacy of adjoining property
(1) A complying development certificate for development must be issued subject to a condition that if the development involves an excavation that extends below the level of the base of the footings of a building on adjoining land, the person having the benefit of the certificate must at the person’s own expense:
(a) protect and support the adjoining premises from possible damage from the excavation, and
(b) where necessary, underpin the adjoining premises to prevent any such damage.
(2) The condition referred to in subclause (1) does not apply if the person having the benefit of the complying development certificate owns the adjoining land or the owner of the adjoining land has given consent in writing to that condition not applying.