Design and build: construction
During the construction stage the contractor takes possession of the site and carries out the construction works. Once the works are complete, a certificate of practical completion is issued and the site is handed back to the client.
 Starting the work stage.
Before work on site proceeds, the client and contractor confirm that that suitable welfare facilities have been provided by the contractor and the contractor (in their role as as principal contractor) confirms that a suitable construction phase plan has been prepared.
The principal designer assesses and gives advice about any additional design information that is prepared by the contractor, specialist contractors or specialist designers (including temporary works) and the contractor updates the construction phase plan and re-issues it as required.
Where there are any proposed variations, procedures for their valuation are implemented (as described in the contract). Where changes exceed the delegated authority of the employer's agent, approval should be requested from the client.
The employer's agent co-ordinates site inspections, issues instructions as required and assesses any claims for extension of time or loss and/or expense (perhaps with advice from independent client advisers).
The contractor prepares interim applications for payment. The employer's agent checks applications for payment and issues payment notices to the contractor of the amount to be paid. The notices must be issued within five days of the dates for payment set out in the contract. If the client intends to pay less than the amount on the notices, pay less notices must be issued giving notice of the amount that will be paid and the basis for its calculation. The client then makes payments to the contractor by the final date for payment.
The employer's agent holds regular construction progress meetings and submits progress reports to the employer's agent. The employer's agent then prepares construction progress reports for the client.
 Preparing for occupation.
If they have not already done so, the client begins preparations for occupation of the development, including the preparation of an operational policy and migration strategy setting out how they will manage the transition into and the operation of the new facility.
The client may have an 'occupation services contract' for delivering and installing equipment, fixtures and furniture (sometimes from other premises). This contract may also pick up small building changes that are considered too costly to be instructed under the main contract.
 Inspections, commissioning and testing.
If it has not already been done, the client appoints an in-house or outsourced engineering team to witness testing and commissioning and to take over the running of the services as soon as practical completion is certified.
The client's engineering team co-ordinates procedures for inspections, commissioning, testing and client training in relation to building services and the client agrees procedures for inspections, commissioning, testing and client training in relation to other aspects of the building with the contractor.
The contractor prepares a draft building owner's manual, building log book and if required by the employer's requirements, a building user's guide. The principal designer completes the health and safety file.
The contractor arranges for final inspection of the works by the building control inspector (or approved inspector) and arranges for the issue of a building regulations completion certificate. NB Within 5 days of the completion of the building, the contractor must notify building control that the works have been carried out in accordance with the specification submitted with the building emission rate (BER) calculations, or the changes that have been made (see emission rates for more information).
The contractor prepares an interim application for payment, including the release of half the retention. The employer's agent checks application for payment and issues the certificate of practical completion and payment notice to the contractor of the amount to be paid. If the client intends to pay less than the amount on the notice, a pay less notice must be issued giving notice of the amount that will be paid and the basis for its calculation. The client makes payment by the final date for payment. This will include the release of 50% of the retention.
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