Civil Engineering Reference
In-Depth Information
Chapter 13
Variations
13.1 Introduction
Use of the word 'variations' in building contracts usually refers to a change
in the works instructed by the architect, contract administrator or the em-
ployer as the case may be (but see the quite different 'variation of contract'
considered in Chapter 4, section 4.3). There are clauses permitting variations
in all standard form contracts. If there was no such clause in lump sum
contracts, the contractor could not be compelled to vary the works and he
could insist upon completing precisely the work and supplying precisely
the materials for which he has contracted. No power to order variations
would be implied
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. Although standard contracts contain a clause permit-
ting variations, the power is not unfettered. A variation may not be ordered
if it changes the whole scope and character of the works. To determine
whether this has been done in any particular case, reference must be made
to the recital which sets out the work to be done. As a broad rule of thumb, if
the variation does not invalidate the description in the recital, it is unlikely
to be a variation which changes the whole scope and character of the works.
To a large extent the point is academic, because a contractor will usually
welcome the opportunity to carry out additional work and thereby earn
money in the valuation of the variation and possibly in the formation of a
claim for disruption or prolongation.
Variations are a fact of life in building contracts. There can only be a
minority of contracts of any size in which the subject matter when com-
pleted is identical in every respect with what was contemplated at the
outset.
Variations are inevitable in even the best-planned contracts simply be-
cause, in a matter as complicated as the construction of a building, it is
virtually impossible for the building owner and his design team to foresee
every eventuality. However, variations often arise quite unnecessarily,
simply because the building owner had been unable to make up his mind at
the design stage about precisely what he does want or because of lack of
foresight on the part of the design team or perhaps, more commonly, because
the design team have allowed themselves to be pushed towards a start date
which is not realistically achievable. On hospital projects, for instance, med-
ical science advances so rapidly that it is often necessary tomakemajor design
