Civil Engineering Reference
In-Depth Information
quantities should be valued. The valuation of as-built quantities is distinct from the
valuation of variations (though the same valuation rules may apply).
4.5.2 Variations under the SBC, the SBC/DB and the NEC3
In the SBC, the term 'Variation' is defined in detail in clause 5.1 and there are two
distinct parts to the definition:
First, it means the alteration or modiication of the design, quality or quantity of the
works. his includes the addition, omission or substitution of any work; the alteration
ofthekindorstandardofanyofthematerialsorgoodstobeusedintheworks;or
theremovalfromthesiteofanyworkexecuted,orSiteMaterials,otherthanwork,
materials or goods which are not in accordance with the Contract.
Second, it means the imposition by the Employer of any obligations or restrictions
in regard to four specified matters or the addition to, or alteration or omission of,
any such obligations or restrictions imposed by the Employer in the Contract Bills or
Employer's Requirements (for any Contractor Designed Portion) in relation to these
matters. The four specified matters are: (1) access to the site or use of any specific
parts of the site; (2) limitations of working space; (3) limitations of working hours;
and (4) the execution or completion of the work in any specific order. In the SBC/DB
clause 5.1, the term 'Change' is used in place of 'Variation'. he meaning is essentially
the same as in the SBC, but the alteration or modification in the design, quality or
quantityoftheworkscanonlybemadebyachangetotheEmployer'sRequirements.
There is no provision for making a change to the Contractor's Proposals.
The Architect's powers in respect of Variations under the SBC are set out in clause
3.14. 3.14.The Architect is expressly given the power to issue instructions requiring a Vari-
ation and any instruction issued by him in this regard is subject to the Contractor's
right of reasonable objection under clause 3.10.1, where the instruction relates to a
Variation under clause 5.1.2, i.e. the imposition of any obligations or restrictions in
regard to any of the specified matters. Similar powers in respect of a Change are given
to the Employer under clause 3.9 of the SBC/DB. In addition to the Contractor's right
of reasonable objection under clause 3.9.2 where the instruction relates to a Change
under clause 5.1.2, clause 3.9.1 of the SBC/DB provides that the Employer may not
effect a Change which is, or which makes necessary, an alteration or modification
in the design of the Works without the consent of the Contractor, which is not to be
unreasonably withheld or delayed. here is an equivalent provision of sorts in the SBC
clause 3.10.3 insofar as the instruction 'injuriously affects the efficacy of the design of
the Contractor's Designed Portion', which allows the Contractor to give notice of such
injurious effect, in which event the instruction shall not take effect unless confirmed
by the Architect.
Under the SBC the Architect also has the power to issue instructions to expend
provisional sums included in the Contract Bills or in the Employer's Requirements
(clause 3.16). A similar power is given to the Employer under clause 3.11 of the
SBC/DB. It should be noted that the NEC3 does not contain any provisions for
provisional sums. The Architect is empowered to sanction in writing any Variations
made by the Contractor otherwise than pursuant to an instruction of the Architect.
