The main contractor undertakes to carry out and complete the works for a specified price.

The main contractor may employ sub-contractors to carry out some of the works. Usually, specialist trade sub-contractors can do a better and cheaper job than the main contractor themselves.

Thus, the main contractor can spread their risk to sub-contractors.

Sub-contracts should be “back-to-back” with the main contract.

The main contractor is responsible for all the works, including defaults by his or her sub-contractors, but he can claim such defaults from their sub-contractors, or join them into any proceedings brought by or against the employer.

Sub-contractors may be “domestic” or “nominated”.

Main contractor require indemnity to nominate sub-contractors.

The site insurance policy should include sub-contractors.

Domestic sub-contractor: A sub-contractor selected by the main contractor.

Nominated sub-contractor: A sub-contractor who the main contractor is instructed to employ for a particular works-package.

CAR: Contractor's All Risk Policy.

FIDIC: The International Federation of Consulting Engineers, who produce standard forms of contract for the construction and engineering sectors, including the Red Book.

Red Book: FIDIC Conditions of Contract for Construction for Building and Engineering Works designed by the Employer, 1999 Edition.