A variation, also known as a change order or change directive, refers to any modification, addition, or omission to the original scope of work specified in the contract. Variations can arise for various reasons, including changes in project requirements, design modifications, unforeseen site conditions, or employer-requested alterations to the original specifications.

Key points regarding variations in construction contracts include:

1. Nature of Changes:
   Variations can involve changes to the design, specifications, quantities, or the overall scope of work. They can be initiated by the employer, the architect, the engineer, or other parties involved in the project, subject to the terms of the contract.
2. Contractual Mechanism:
   Construction contracts typically include provisions outlining how variations are to be managed and processed. This may involve formal procedures for initiating, documenting, and approving variations.
3. Variation Orders:
   A variation order is a formal document issued by the employer or contract administrator instructing the contractor to proceed with a specific change in the scope of work. It outlines the details of the variation, including the nature of the change, any adjustments to the contract sum or completion date, and other relevant information.
4. Valuation of Variations:
   The contract may specify how variations are priced. This could include a predetermined formula, rates, or a mechanism for negotiating the cost of the variation. Valuation may cover additional costs or, in some cases, result in a reduction in the contract sum.
5. Impact on Time and Cost:
   Variations may impact the project timeline and budget. Depending on the nature and complexity of the variation, it may lead to an extension of time for completion and adjustments to the contract sum to account for additional costs or savings.
6. Contractual Notice Requirements:
   The contract often includes requirements for the contractor to provide formal notice when encountering circumstances that may lead to a variation. This notice is crucial for the timely processing and approval of variations.
7. Employer Approval:
   Variations typically require approval from the employer or contract administrator before the contractor proceeds with the changed work. This ensures that the employer is aware of the implications on cost, time, and other project considerations.
8. Record Keeping:
   Proper documentation is essential for variations. Both the employer and the contractor should maintain detailed records of variation orders, including the reasons for the changes, the impact on the project, and the agreed-upon adjustments.

Variations are a common aspect of construction projects and are often managed to accommodate evolving project requirements and unexpected challenges. Proper communication, documentation, and adherence to contractual procedures are essential for effectively managing and implementing variations while maintaining project integrity.