4.2.4.1.

(1) The design of foundations, excavations and soil – and rock-retaining structures shall be based on a subsurface investigation carried out by a person competent in this field of work, and on any of the following:

(a) application of generally accepted geotechnical and civil engineering principles by a person especially qualified in this field of work as provided in this Section and other Sections of this Part,

(b) established local practice where such practice includes successful experience both with soils and rocks of similar type and condition and with a foundation or excavation of similar type, construction method, size and depth, or

(c) in situ testing of foundation units such as the load testing of piles, anchors or footings carried out by a person competent in this field of work.

(2) The foundations of a building shall be capable of resisting all the loads stipulated in Section 4.1., in accordance with limit states design in Subsection 4.1.3.

(3) For the purpose of the application of the load combinations given in Table 4.1.3.2.v1, the geotechnical components of loads and the factored geotechnical resistances at ULS shall be determined by a suitably qualified and experienced person.

(4) Geotechnical components of service loads and geotechnical reactions for SLS shall be determined by a suitably qualified and person.

(5) The foundation of a building shall be designed to satisfy SLS requirements within the limits that the building is designed to accommodate, including total settlement and differential settlement, heave, lateral movement, tilt or rotation.

(6) Communication, interaction and coordination between the designer and the person responsible for the geotechnical aspects of the project shall take place to a degree commensurate with the complexity and requirements of the project.