Part 3.1.1 Earthworks
Appropriate Performance Requirements
STATE AND TERRITORY VARIATIONS
STATE AND TERRITORY VARIATIONS
Except for Table 184.108.40.206 as referenced by Figure 220.127.116.11 and except for Clause 18.104.22.168(b) for determination of a normal site as referenced by Clause 3.2.1, Part 3.1.1 does not apply in New South Wales.
Note: In New South Wales requirements for shoring and adequacy of excavation works are a prescribed condition of development consent. In addition consent authorities can place specific controls on siteworks associated with the construction of a building, by imposing further conditions of development consent. Information addressing siteworks can be found in the Department of Planning and Environment – Act and Regulation note "Health, safety and amenity during construction".
Acceptable construction practice
The work is undertaken in normal site conditions.
For the purposes of this Part, normal site conditions are defined by the following parameters—
moisture conditions on site are as a result of seasonal and climatic changes; and
large trees have not been recently removed from the site; and
soil moisture conditions have not been significantly modified by the removal of buildings or other structures; and
drainage on the allotment is maintained.
The provisions described in Part 3.1.1 will enable earthworks to be carried out safely and avoid potential damage to adjoining structures and property through the soil collapsing or subsiding during building works. Exceptional site conditions (including the effects of torrential rain) may need special consideration and additional advice from appropriately qualified people should be considered.
State and Territory legislation may also have requirements that affect the excavation, especially in relation to adjoining property and notification to owners of that property. Advice should be obtained from the appropriate authority before commencement of works.
Excavation and fill utilising unprotected embankments can be undertaken in accordance with—
Table 22.214.171.124 for general earthwork; or
126.96.36.199 for excavation adjacent to vacant adjoining property; or
188.8.131.52 for excavation adjacent to existing buildings; or
184.108.40.206 for fill adjacent to adjoining property.
220.127.116.11 Excavation adjacent to vacant adjoining property
Excavation work, using unprotected embankments, adjacent to another allotment can be undertaken provided—
there are no buildings or structures on the adjoining allotment within 3 m of the allotment boundary adjacent to the excavation; and
the excavation commences at the allotment boundary and is within the area defined as being suitable for excavation in Figure 18.104.22.168; and
the slope of the unprotected embankment of the excavation complies with the appropriate soil classification slope described in Table 22.214.171.124.
126.96.36.199 Excavation adjacent to existing buildings
Excavation work for footings, drainage trenches or other similar works, adjacent to existing buildings can be undertaken provided—
the angle to determine the safe area for excavation is taken from the bottom of the shallowest point of the existing footing in accordance with Figure 188.8.131.52; and
the excavation is within the area defined as being suitable for excavation in Figure 184.108.40.206; and
the slope of the unprotected embankment of the excavation complies with the appropriate soil classification described in Table 220.127.116.11; and
for footing excavation adjacent to existing footings—
the footing is placed as soon as practicable after exposing the existing footing; and
the existing footing, where on an adjoining property, is completely isolated from the new footing by means of a flexible bond breaker not less than 10 mm thick; and
the adjoining footing is not left exposed at the completion of works.
|EXCAVATION AFFECTING ADJOINING PROPERTY|
|Note: The angle for line A–A is defined in Table 18.104.22.168.|
|EXCAVATION ADJACENT TO EXISTING BUILDINGS|
|Note: Line A–A is defined in Table 22.214.171.124 and taken from the bottom of the shallowest point of the existing footing.|
Filling works may be carried out provided—
where the fill is deeper than existing soil level, the gradient of the fill complies with Table 126.96.36.199; and
where the fill is to be used to support footings or slabs, it is placed and compacted in accordance with Part 3.2.
(*see Part 3.2.4 for material description)
|EMBANKMENT SLOPES H:L|
|Compacted fill (see Part 3.2)||Cut|
|Stable rock (A*)||2:3||8:1|
|Soft clay||Not suitable||2:3|
|Soft soils (P*)||Not suitable||Not suitable|
1. Retaining walls or other types of soil retaining methods must be installed where—