Civil Engineering Project Management (4th Edition)

62 Civil Engineering Project Management
In drawing up the specification it is advisable to plan out beforehand subjects
to be dealt with. An order such as the following might be adopted.
1. demolition, site clearance;
2. excavation;
3. piling;
4. concrete;
(a) in situ;
(b) reinforcement;
(c) formwork;
(d) pre-cast;
(e) pre-stressed;
5. pipe-laying (might be put later);
6. steelwork (structural);
7. brickwork/blockwork/masonry;
8. roofing;
9. cladding (if special);
10. carpentry;
11. finishing trades (as necessary);
12. roads, site restoration, fencing.
It is not advisable to use three or more levels of decimal numbering of sections,
such as ‘2.1.1’, ‘2.1.2’, etc. Only the section headings under each class of work
need be numbered; sub-sections can be un-numbered and identified by a left
hand heading, and paragraphs are not numbered. This permits insertion of late
additions without disturbing any numbering.
When drafting the specification, care should be taken to ensure coverage of
all types of work that appear on the drawings. In civil engineering contracts
the specification sets out all quality requirements so these must be complete.
The items in the bill of quantities only need sufficient description for the item
to be identified for the purposes of payment. If an item in a bill of quantities
appears with extra description which is not in the specification, a contractor
might argue that the item with the added description requires additional payment.
(See Section 4.4 where it is noted that under JCT conditions for building
work the contrary practice applies.)
There have been differences of opinion among engineers as to the merits of
‘method’ as against ‘performance’ types of specification. A method specification
for concrete quotes not only the materials and quantities of them to be used to
make various grades of concrete but also the strengths and other physical characteristics
to be achieved together with requirements for handling and placing.
A ‘performance’ specification would stipulate only the strength and other physical
characteristics to be achieved. This, it is said, leaves the contractor greater freedom
to decide how he will achieve the performance criteria. However, opponents
of performance specification point out that control by testing is only possible
(in the case of concrete) 28 days after placing, and such tests may not provide
sufficient proof that the structure will perform satisfactorily in the long term.
If defects appear later, how is the contractor to be held responsible? Traditional