11 INTERIM PAYMENTS
The Contractor is entitled to payments at intervals during the course of the
works, provided he applies for them in accordance with clause 14.3.
He must submit a Statement to the Engineer or Employer after the end of
the period of payment stated in the contract (or, if none is stated, at the end of
each month).
This Statement must include an estimated contract value of the works and
Contractor ’ s documents produced up to the end of the relevant month. It
must give effectively an account of sums to be added or deducted between the
parties and provide supporting documents necessary for the Engineer or
Employer to verify the amounts claimed. It has also to be accompanied by the
Contractor ’ s progress report (under clause 4.21) for the period to which the
Statement relates.
No payment is to be made until the Employer has received the performance
security.
Thereafter, in the Yellow Book, the basic procedure is that the Engineer,
within 28 days of receiving the Statement and supporting documents, issues
to the Employer an interim payment certificate stating the amount which the
Engineer fairly determines to be due to the Contractor. Payment may be with-
held for defective work or failure to perform obligations under the Contract,
subject to notice to the Contractor.
In the Silver Book, again subject to receiving the performance security, the
Employer is to give a notice to the Contractor within 28 days of receiving the
Statement and supporting documents of items in the Statement with which he
disagrees, with details. Again, the Employer can withhold sums in respect of
defective work or any failure by the Contractor to perform his obligations,
subject to notice.