Construction management: detailed design

This stage is concerned with developing the detailed design and technical design for the project. It is also likely to include making a detailed planning application and applications for statutory approvals. In this work plan we suggest the construction manager is appointed on completion of concept design. Earlier or later appointment will result in some activities being re-allocated between the consultant team and the construction manager (for example the role of cost consultant).

[edit] Starting the work stage.

The client updates the project execution plan to reflect comments made at the end of the previous stage. The lead consultant co-ordinates a start-up meeting attended by the consultant team, construction manager (if appointed) and the client to issue revised documentation, to pass on comments made at the end of the previous stage and to agree the programme for the stage.

The consultant team, construction manager or the client may identify a requirement to appoint additional consultants, such as an approved inspector or party wall surveyor. Go to work stage: construction management: appointment. If an approved inspector is appointed, the client and approved inspector must jointly issue an 'initial notice' to the local authority. Unless the local authority reject the initial notice, responsibility for verifying that the project complies with the building regulations will then fall to the approved inspector.

[edit] Developing detailed design options.

The lead designer co-ordinates the development of a detailed design based on the approved concept design and co-ordinates consultation about the functional aspects of the detailed design with the client's user panels and champions, and if necessary external stakeholders.

The lead designer co-ordinates consultations with statutory authorities, non-statutory authorities, insurance providers, neighbours etc. The client may need to issue party wall notices and to appoint party wall surveyor(s). Go to work stage: construction management: appointment.

The lead designer co-ordinates development of the detailed design to take on board comments made during consultations and the construction manager (or cost consultant) updates the elemental cost plan and cash flow projection.

[edit] Developing the outline specification.

The lead designer discusses with the consultant team and construction manager the likely scope of specifications that will be required and co-ordinates the development of the outline specification. This might require that:

• The client and construction manager identify requirements for equipment to be provided within the main contract, or equipment with installation requirements to be provided within the main contract.
• The lead designer co-ordinates the sourcing of materials, components and assemblies for approval by the client.
• The lead designer co-ordinates the identification of requirements for design by specialist trade contractors.
• The construction manager investigates opportunities for machining components.

[edit] Developing the detailed design.

The lead designer co-ordinates the consultant team and construction manager to undertake a design review of the detailed design and outline specification and then develop the detailed design and outline specification to take on board comments made. The construction manager (or cost consultant) updates the elemental cost plan and cash flow projection.

The lead consultant presents the final detailed design to the client and requests approval to begin technical design, to appoint specialist trade contractors and if necessary to make a detailed planning application (or reserved matters applications if a previous application was made for outline planning permission) go to work stage: Construction management: planning permission.

[edit] Considering the tendering and construction processes.

The construction manager develops a site logistical plan selecting and positioning site access points, temporary roads, plant and equipment, water, drainage and electricity and other temporary infrastructure requirements, and space allocations for trade contractor facilities.

The construction manager in consultation with the consultant team produces an overall strategy for packaging the work into a series of trade contracts and prepares a draft preliminaries document.

The construction manager prepares draft tender documents and proposed contract conditions for the trade contracts including relevant pre-construction services. This information is circulated to the consultant team and client for comment. This information might need to be used for the early two-stage appointment of specialist trade contractors (see below).

NB. Throughout this stage, the construction manager investigates all opportunities for standardising assemblies and components and maximising off-site prefabrication (where this is practical, economical and assists the programme).

[edit] Appointing specialist trade contractors to assist in the technical design.

The client considers advice from the consultant team and construction manager on the need to appoint specialist trade contractors to assist in preparation of the technical design. NB Appointment of specialist trade contractors may be subject to OJEU procurement rules.

If necessary, the construction manager co-ordinates the preparation of tender documentation for specialist trade contractors.

If appropriate, the client advertises or arranges to have advertised the specialist trade contracts, and prepares or arranges for the preparation and issue of pre-qualification questionnaires. It may be appropriate to hold pre-tender interviews with prospective tenderers. A short list of prospective tenderers is then prepared.

The construction manager issues tender documentation to prospective tenderers and co-ordinates the review of submitted tenders. The construction manager assesses the financial offers of tenderers and carries out financial checks to ensure the contract is within the financial capability of the tenderers (ideally the value of the contract should be no more than 20% of the annual turnover of the tenderer). The designers offer advice where appropriate. Interviews may be carried out if necessary.

If necessary, based on the price of the tenders received, the client may instruct the construction manager to amend the design and seek revised tenders, or to carry out a value management exercise. If necessary the consultant team and construction manager (and perhaps the client) then carry out a value management exercise, amend the design and seek revised tenders.

Once instructed by the client, the construction manager co-ordinates negotiations with the preferred specialist trade contractor(s).

The client appoints the preferred specialist trade contractor(s) to assist in preparation of the technical design and the construction manager organises approval and payment procedures for the specialist trade contractors.

[edit] Preparing the technical design.

If necessary, the lead consultant organises a specialist trade contractors' start-up meeting.

The lead designer co-ordinates the preparation of the technical design including the incorporation of design by specialist trade contractors. They may wish to appoint a design co-ordinator to be responsible for co-ordination and integration of the technical design.

The lead designer co-ordinates the consultant team and construction manager to undertake a design review of the technical design and, if appropriate, arranges visits to the specialist trade contractors' premises to assess samples or mock-ups and to witness tests. Where appropriate, samples are obtained for approval by the client.

The lead designer co-ordinates amendment of the technical design in line with comments made during design review and the construction manager (or cost consultant) develops the elemental cost plan into an approximate quantities cost plan and revises the cash flow projection.

[edit] Preparing a detailed design report.

The lead designer co-ordinates consultations with the statutory authorities to establish submission requirements for statutory approvals. The client may appoint an approved inspector to consider building regulations submissions (rather than making submissions to a local authority inspector). Go to work stage: Construction management: appointment.

The lead consultant co-ordinates the preparation of a detailed design report and issues this to the client. The client reviews the detailed design report and assesses the need for changes to the design or for a value management exercise. If instructed, the construction manager arranges a value management exercise with the consultant team, specialist trade contractors and perhaps the client and directs the consultant team and specialist trade contractors to amend the technical design.

Once the client is satisfied, the lead consultant freezes the technical design and specifications, introduces change control procedures and gives instructions for the lead designer to co-ordinate applications for statutory approvals and other approvals.