Promoting collaborative working within the construction industry
Section 3.3.3 'Smaller projects' describes the use of the schedule of work, supported by a reference specification, forming a two-part project specification. Information that is priceable and variable project to project should be included in the schedule of work or the preliminaries. Statements of quality and workmanship that are deemed to be of general good practice, not varying project to project, should be included in the reference specification.
The schedule of work, reference specification and drawings should be structured and drafted to form a single set of co-ordinated production information. The documents should provide clear, comprehensive and unambiguous information that will allow the construction works to be completed efficiently.
The main difference between a specification (as discussed in Section 4) and a schedule of work is that the latter also functions as the pricing document. The structure of the schedule of work should reflect the needs of both specifier and constructor for pricing and valuation in addition to construction and quality control.
As a rule, the more detailed the level of pricing, the more precise the process of estimating and valuation of variations. The schedule of work should therefore identify and describe each and every price-significant item of finished work. Each such work item should be:
Work items will need to specify attributes or properties, which should be given as sub-items. In specifying the attributes it is important to minimise repetition, e.g.:
Constructions consist of work items, grouped together to define clearly recognisable parts of the building (either whole elements or parts of elements) or locations of the building (e.g. repair/renewal work in a certain room). They are cost significant in that they provide a context to aid visualisation of the work involved, and form a price collection structure for the work items. The nature of the constructions and their arrangement will be determined by the nature of the work, particularly whether it is new build or alterations:
The constructor will need to visit the site to assess the work and take dimensions. The constructions should therefore be formulated and arranged by location, room-by-room and elevation-by-elevation (see Figure 5.1). Cross-referencing to previous similar items will avoid excessive repetition of descriptions occurring in several locations.
Figure 5.1 Example construction for alteration work
The constructor will need to correlate the descriptions with the drawings to assess the context and take dimensions. The constructions should therefore be formulated and arranged by elements, as in Figure 5.2. This will allow groups of like types of work to be brought together, significantly reducing the size of the document.
130 Softwood boarding on joists
Timber board flooring (K20)
Softwood floor joists (G20)
Joist hangers (G20)
Solid softwood strutting at partition positions (G20)
Softwood herringbone strutting between floor joists (G20)
Softwood noggings (G20)
Lateral restraint straps (G20)
Total for softwood boarding on joists
Figure 5.2 Example construction for new work
The tendering constructor has the option of pricing each work item or, where the quantity is small and to save time, the whole construction as one lump sum.
Projects may contain both new and alteration work, in which case the schedule of work may, if considered appropriate, be divided into two such parts, starting with the work to existing and followed by the elementally based sections for new work.
Organisation of the schedule of work into constructions arranged by elements and/or locations will facilitate:
Linking between the drawings and schedule of work should operate as follows:
470 Opening in existing cavity wall (see Figure 5.1)
130 Softwood boarding on joists (see Figure 5.2)
To ensure that the construction reference numbers and headings on the drawings are given correctly they should be copied and pasted from the schedule of work. The annotations on the drawings should not duplicate other information contained within the schedule of work.
Appendix S3 gives an example annotated drawing, related schedule of work constructions, and a related section of reference specification.
Section 3.1.2 discussed location information schedules, traditionally regarded as drawings, and proposed that they can and should now be regarded as part of the specification. Section 4.1.4 discussed location information on larger projects.
On smaller projects where a schedule of work is used, the use of drawn location schedules introduces the risk of duplicating the pricing of the work and also the possibility of conflicting description. For example, where a schedule of work priced work item includes the size of a door, to also include the size in a separate location schedule may give rise to a discrepancy. The use of location information schedules is therefore generally best avoided on smaller projects. Where they are used a consistent approach should be followed that provides the information in one place only: the location schedule should not duplicate the descriptive and pricing functions of the schedule of work.
The combinations of specification variant that occur on the project are analysed, and the various 'types' are defined, e.g. the door leaf types, doorframe types, ironmongery 'set' types, etc. To avoid or minimise repetition each type of door leaf, doorframe, ironmongery set, etc is fully described in one priceable work item within the relevant elemental section of the schedule of work (in this example Doors) with references to the relevant door numbers, see Figure 5.3:
TYPE 1 INTERNAL TIMBER DOORFRAMES:
TYPE 2 INTERNAL TIMBER DOORFRAMES:
Figure 5.3 Work items giving location information
On simple projects this information may be sufficient, but if the project is complex a locational schedule can be provided for use during construction, summarising the way in which the types combine - see Figure 5.4. The same principle can be applied to other common types of location schedule, e.g. internal finishes.
DOORS 2, 3, 4, 9 and 14:
DOORS 6 and 8:
Figure 5.4 Location schedule for use with complex information
Each type of work should be fully specified in the first occurring location, e.g. Room 1, Door 1, etc. Subsequent rooms, doors, etc can then be specified at least partly by back reference - see Figure 5.5. In this way each location can be given for separate pricing, without incurring excessive repetition. Where the schedule of work is arranged by locations in this way separate location schedules will obviously be unnecessary.
Figure 5.5 Work item for a particular location