The general aims at this stage are as follows:

• Translation of sketch ideas into viable forms of construction.
• Selection of appropriate and economical forms of construction and materials.
• Preparation of essential detailed information needed for costing, measurement and construction.
• To control the development of detailed design work in accordance with agreed initial budgets and cost planning.
• To maintain communication between all the members of the design team co-ordinating detailed design development work.
• Incorporation of all mandatory statutory requirements.
• Work towards maintaining the design development programme.

File material could include the following:

Notes, letters and minutes

• Recording exchanges of information between the members of the design team, including sketches of construction ideas and preliminary framework drawings.
• Details of discussions with statutory authorities reflecting requirements or changes to the design as detailed work proceeds.

Checklists

• Question and answer lists exchanged between members of the design team to confirm revised details and specifications.
• Details of client approval to detailed information incorporated into final design work.
• Details of costs of proposed design details and materials, including evaluation of relative economy and implications of changes to design as work proceeds.

Working drawings

• Examples of location, component and assembly plans, elevations and sections showing exactly how elements of construction are to be handled.
• Site layouts for surfaces, drainage, services, external lighting, signage, landscaping and planting, parking arrangements, walls, fences and boundary treatments.
• Floor plans showing location grid and space referencing, floor levels, dimensions, foundations, forms of construction, fixtures and fittings, sanitary goods, fire safety measures, stairs and lifts, services arrangements for heating, power, lighting and communications, internal drainage and plumbing, etc.
• Elevations showing lengths and heights, openings, gutters and downpipes, pipework, extract grilles, overflow pipes, materials such as brick, block, cladding and glazing.
• Sections showing internal dimensions, methods of construction and details of abutments and overlaps.
• Examples of superseded drawings retained for historical reference only.

Specifications

• Examples of comprehensive description of materials, products and assemblies including sizes, qualities, colours and workmanship.
• Reference sources for quality assurance, BSs, CPs, etc.
• Examples of colour schemes and specialist layouts such as ceiling tiles, floor tiles or wall finishes.

Schedules

• Examples of schedules for repetitive elements such as doors, windows, ironmongery and manholes.

Details of drawings issues

• Lists of principle drawings needed for tendering, details of drawings and documents supplied to nominated subcontractors and suppliers for estimates to be included as PC or provisional sums.
• A register of all drawings prepared by the building designer and other members of the design team including, structural information, power, lighting, heating and ventilation and communications.
• An example of a drawings issue slip sent to members of the design team to confirm transfer of information.

Measurement

• Details of information supplied to the QS for inclusion in the BQs including full specifications, Prime Cost Sums, provisional sums and contingencies.
• Query sheets from the QS requesting clarification of points of information.
• A preliminary BQ for approval prior to printing.
• A BQ ready to be sent out to tender.

CDM issues

• Risk assessments for elements of the design.
• Risk assessments for materials and construction processes.