(Правовое руководство по составлению строительных контрактов)
As used in the Guide, the term "variation" refers to a change in an aspect of the construction of the works from that required under the contract documents. During the course of construction of the works, situations may be encountered which make it necessary or advisable to vary certain aspects of the construction. It is advisable for the contract to contain provisions setting out the circumstances under which a contractor is obligated to implement a variation. In formulating contractual provisions concerning variations, the parties should attempt to strike an appropriate balance among various interests (paragraphs 1 to 4).
The parties may wish to consider three basic approaches to variations sought by the purchaser. Under the first approach, the contract would obligate the contractor to implement a variation ordered by the purchaser, so long as the variation ordered met certain criteria set forth in the contract. Under the second approach, the contract would obligate the contractor to implement a variation ordered by the purchaser unless he objected to it upon reasonable or specified grounds. Under the third approach, a variation would require the written consent of the contractor. The contract could incorporate one or any combination of these approaches. It would be useful for the contract to contain provisions concerning the settlement of disputes between the parties as to whether the purchaser was entitled to order a variation (paragraphs 5 to 7).
The parties may, in some cases, consider it appropriate to provide in the contract for reasonable adjustments to be made in the contract price and in the time for completion by the contractor in the event of a variation. In such a case, the contract may contain a mechanism for the contractor to inform the purchaser of the contractor's contentions concerning the impact of the variation on the contract price and time for completion in order to enable the purchaser to consider whether, in view of the likely impact, he wishes to insist upon the variations. Whether or not such a mechanism is contained in the contract, the contract may obligate the parties to attempt to settle between themselves the amounts of the adjustments to be made in accordance with criteria set forth in the contract, and entitle either party to refer for settlement a dispute as to the amount of an adjustment (paragraphs 8 to 11).
With respect to variations which the contractor is obligated to implement, the parties may wish to consider restricting the scope of such variations (paragraphs 12 and 13). With respect to variations to which the contractor may object, the contract may entitle the contractor to object on reasonable grounds, or may specify particular grounds upon which he may object (paragraph 15). The contract may contain procedures with respect to the ordering and implementation of both of these categories of variations (paragraphs 14 and 16 to 18).
With respect to variations which require the consent of the contractor, the contract may provide that variations requested by the purchaser must be implemented by the contractor only if he consents to them in writing (paragraph 19). It would be in the interest of the purchaser if variations proposed by the contractor were not to be implemented unless they were agreed to in writing by the purchaser (paragraphs 20 to 22).
The contract may contain particular provisions dealing with changes in construction in cases of unforeseeable natural obstacles and changes in local regulations (paragraph 23).
For cases in which a variation is to result in an adjustment of the contract price, it is desirable for the contract to provide that the adjustment is to be by a reasonable amount. It would be useful for the contract to contain guidelines to assist in the determination of what amount of adjustment is reasonable. These guidelines may vary depending upon the type of contract (paragraphs 24 to 32).