Common items to be specified

 

Drawings and models

Drawings and models are content to be referred to in contract-specific specifications. The WSR schedules ask for relevant drawing or model reference(s) and may ask for information that is shown on drawings for example widths or heights.

Asking for information that is typically shown on drawings and models, hence producing the same information in multiple places, is not considered to be good practice. However, tabular information is important to support machine readability and in future it will be easily extracted by models, which can be used to derive both drawings and schedules. We are in a transition area now and we do not want to inhibit future trends including better management of asset data information.

As a general principle, information should not be duplicated. Where information is more practical to be provided on drawings and models, it will be provided in that way. Where possible, information should also be provided in a tabular format.

What if:

  • An entire table is to be replaced by a drawing: this case should rarely apply; in such circumstances, share this feedback with the technical author using our feedback form.
  • Only selected cells are to be replaced by a drawing: Use the following text: ‘Refer to drawing xxx’ or similar.
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Contractor design elements

DMRB documents give design requirements regardless who undertakes design. In doing so, it allows for (i) traditional route where design output is communicated to constructors through WSR template and (ii) other procurement arrangements such as design and build etc.

What if:

  • Something is always contractor design: the updated MCHW clearly provides contractors with information on what they have to design, using the phrase ‘Contractor design’. The specifier would not have access to that information when preparing the specification, hence there is no reference to WSR in the relevant SHW requirement in these circumstances. What the MCHW would typically provide is:
    • a requirement on documentation submission by the contractor, rather than specific information to be filled in by the specifier through the WSR;
    • a reference to relevant design standards – the DMRB would then clarify the outcomes and/or provide performance characteristics and the proof needs to come as documentation submission from the contractor;
    • the contract specific information contractors need in order to do the design (i.e. design input criteria and data). 
  • Something is sometimes contractor design and sometimes it is not: The updated MCHW clearly provides contractors with information on what they have to design using the phrase ‘Contractor design’, as well as a reference to the WSR. What the MCHW would typically provide is:
    • the individual items to be contractor design, which are detailed in the relevant WSR;
    • a reference to relevant design standards – the DMRB would then clarify the outcomes and/or provide performance characteristics and the proof needs to come as documentation submission from the contractor;
    • the contract specific information contractors need in order to do the design (i.e. design input criteria and data).

See also GC 101 covering Contractor design. Whilst the above does not change current practice, it is an area where inconsistencies have been found due to confusion on the approach to be taken.

As a general principle, the specifier shall leave the text blank if there is nothing to convey. Not all fields in all schedules have to be specified all the time if not needed, the options are there for when the information is available.

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Manufacturers product information

There may be instances where the contract-specific specification requires information that is understood to be provided by manufactures / installers, and the designer may not have this information available at design stage to pass on the specifier to complete the WSR templates. This can create confusion over the status of the specification (sometimes seen as a ‘live’ document) and specific roles and responsibilities.

The contract-specific specification is not a live document. Any change after contract award are treated as compensation events. Moreover, there are only two parties in the contract: client and contractor. Therefore, manufacturers are not a relevant party unless they are the contractor. Similar to contractor designed elements, what the updated MCHW provides is a requirement on documentation submission by the contractor, rather than specific information to be filled in by the specifier through the WSR template. If in doubt, share your feedback with the technical author using our feedback form.

As a general principle, the specifier shall leave the text blank if there is nothing to convey. Not all fields in all schedules have to be specified all the time if not needed, the options are there for when the information is available.

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