Transcript Pre-Contract Procedures

Pre-Contract Procedures
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Pre-contract Stages
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Inception
Feasibility
Scheme Design
– Outline proposals
– Detailed design
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Production information
Bills of quantities
Tender action
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Inception
• What is the purpose of the building
• Why it needs to be build
• What is to be built
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• The client appoints architect to oversee the
design and construction of the project.
• After the signing of an agreement between the
client and the architect recommends the Q.S.
and Structural Engineer.
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Client clarifies
• The Required time scale – date for commencement
and completion.
• The nature of the project – size and type of facilities
required.
• The site location and topography.
• Financial limits/method of financing.
• Specific requirements – materials, standards.
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Pre-contract Stages
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Inception
Feasibility
Scheme Design
– Outline proposals
– Detailed design
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•
•
Production information
Bills of quantities
Tender action
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Feasibility
• Design team examines the clients proposals to make
sure that there are no major problems or constraints
relating to the proposed type of building and the
selected site.
• Confirmation that:
• the development be able to fulfil its proposed
function
• the technical problems of the project be overcome
economically
• the financial constraints are acceptable
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• investigations carried out in relation to the site
topography, sub soil conditions and the legal
constraints.
• Outline Planning Permission (OPP) applied for.
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Feasibility
• Looks at the potential of the project being
viable
• A number of factors must be Considered
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Considerations
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Financial consideration
Other developments
Competition
Need
Opposition
Support
Planning Controls
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Roads, Traffic Flow and Densities
Availability of land
Site Access
Ransom Strips
Parking Space
Tenure of Land
Restrictive Covenants, Easements and
Rights of Way
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• Tree Preservation Orders
• Preservation Notices
• Archaeological Areas and Ancient
Monuments
• Conservation areas
• Sites of Special Scientific Interest
Population and Socio-economic grouping
• Customer Requirements and Behaviour
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Land availability
• The cost of land is related to its availability. Costs,
therefore, vary widely in different parts of the country.
• Cost depends also on the economic climate and supply
and demand
• In some areas it is becoming increasingly the case that
the choice may be restricted to difficult sites which may
be contaminated, e.g. old gas works sites which have
chemical residues in the ground. Alternatively, they may
be land fill sites which require more expensive
substructures than ‘normal’ sites.
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Ground conditions
• The type of subsoil will affect the ground
works and the choice of foundation and
ground floor construction.
• A comprehensive site investigation is required
to determine the ground water conditions to
ensure that the correct type of foundation is
used and economically designed.
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Site location / access
• The site location may be important in relation
to the availability of labour and materials.
• The size and shape of the site may affect the
design layout and the progress of site
operations during construction.
• Access into the site may also restrict the size
of plant and components or the type of
construction.
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Finacial Considerations
• The Client will probably have a fixed budget for any
particular project and the design team must produce a
satisfactory solution within these cost constraints.
• The cost of any building must consider both capital and
maintenance costs (Cost in use).
– capital costs - these include all the costs associated with the
initial construction of the building and associated works.
– maintenance costs - these include:
– regular maintenance - E.g. window cleaning, re painting etc.
– periodic maintenance - E.g. replacing central heating boiler,
repointing masonry etc.
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• Running costs must be considered i.e. costs of
lighting, heating and air conditioning.
• An outline cost can be estimated by the Quantity
Surveyor at an early stage by the following methods
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Methods of Assessing Construction
Costs
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Elemental Cost Analysis
Cost per unit area
Approximate Estimating
Bills of Approximate Quantities
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Elemental Cost Analysis
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This is based on historical data from
completed projects with the costs broken
down into the elements of construction and
shown on a metre squared basis.
Data for the calculation of costs can be
obtained from a number of sources i.e. the
Royal Institution of Chartered Surveyors
quarterly review of building prices.
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Cost per unit area
• Based on historical data obtained from similar
completed projects on a cost per metre squared
basis.
• Information may be obtained from the developers
own projects or from other developers.
• Easy method to calculate though it is not very
accurate. Best used on simple offices or car parks.
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Approximate Estimating
• Requires detailed information about the design
requirements of the project.
• Cost obtained by taking off quantities and building
up an estimate.
• Data on costs is obtained from sources as Spon’s or
Wessex (these provide up-to-date pricing
information for building work) or from the use of a
number of computer software programmes which
are available.
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Bills of Approximate Quantities
• This method is time consuming in comparison
to those listed above.
• Method requires a Bill of Quantities being
produced before an estimate can be
obtained.
• Most accurate and can be used for tendering.
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Pre-contract Stages
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Inception
Feasibility
Scheme Design
– Outline proposals
– Detailed design
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Production information
Bills of quantities
Tender action
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Scheme Design
• Produced from the Design Brief given to the
architect by the client
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Purpose of the Design Brief
is to provide the design team with as
much information as is possible in
order to ensure that a building
appropriate to the clients needs and
requirements is produced.
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Sketch Plans - Outline Proposals
• Architect prepares proposals to meet Clients
brief.
• These include:
– Outline drawings showing design
– Explanations of what assumptions and main
decisions have been made.
– Forecast of costs and time scale.
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Scheme design
The design developed to include:
– Investigation of individual room requirements.
– Methods and materials to be used.
– External requirements – colours, textures, styles
• The Structural Engineer will require layout drawings
identifying space requirements and idea of services
layout.
• Section sizes for all the main structural elements are
determined.
• Detailed cost plan, report, outline specification and
scheme drawings are produced.
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Detail design – Working Drawings
• The agreed scheme plans / elevations etc. will be
finished and passed onto the Structural and Services
Engineer.
• Architectural and structural detailing work carried out.
• Architect co-ordinates the design process and ensure
that all the interested parties receive the relevant
information as and when required.
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• All drawings checked by the Q.S. to ensure
compliance with the cost targets.
• All the drawings and structural calculations
submitted for Building Regulations Approval and
Full Planning Permission (FPP)..
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Methods of providing a design brief
• Specific Requirements
– This provides a list of specific requirements.
– They are frequently produced on a room to room
basis and are often used by local authorities and
health authorities.
– Although it does not lend itself to
misinterpretation it can restrict the design due to
the requirements being too rigid.
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• Performance Specification
– This gives the designer the standards of performance
which the building is to obtain.
– It is then up to the designer to ensure that these
standards are met, the way that this is done is left to the
designer.
– This method allows the designer some flexibility as to the
design and the materials which are chosen.
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• Open Ended Brief
– This type of brief is often used in conjunction with 'fast
track' techniques, where the project is frequently
designed as work proceeds.
– This gives the design team a certain amount of latitude,
which may work if the project is of a standard type which
is to be disposed of on completion, though is not
recommended for buildings for a specific use.
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User requirements study
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Objectives must be set by the study with
regard to:
The function of the building:
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The persons using the building
Budgetary constraints
Life cycle of the building
Site considerations.
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Design Considerations
• Type of building – Steel, concrete frame
• Cost and availability of materials,
components and labour
• Site conditions
• Location and access to the site
• Amount of area available – type, car parking
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Scheme design
• Outline
• Detail
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Pre-contract Stages
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Inception
Feasibility
Scheme Design
– Outline proposals
– Detailed design
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Production information
Bills of quantities
Tender action
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Production Information.
• Once Building Regulations approval is obtained, a
detailed cost estimate is obtained remainder of
production information produced.
• This includes :• All working drawings – Architectural / structural /
services etc.
• All schedules – door / window / drainage /
reinforcement etc.
• Specifications – construction methods / materials.
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Pre-contract Stages
•
•
•
Inception
Feasibility
Scheme Design
– Outline proposals
– Detailed design
•
•
•
Production information
Bills of quantities
Tender action
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Bill of quantities
• Quantity Surveyor prepares the Bill of Quantities
(BOQ) by taking all the material requirements off
the working drawings.
• This lists, item by item, all the materials and
components which are required to construct the
project.
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BOQ Contains
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Form of Tender
Preliminaries
Preambles
Measured work section
Dayworks
Prime cost and Provisional sums
Final summary
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Preliminaries
• Referred to as Prelims, these are found at the
commencement of the BofQ.
• General items
• Provides extra information to contractors
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Preambles
• Form the specification for materials and
workmanship. The object is to specify all
materials in such a way as to leave no doubt in
the contractors mind - specify BS numbers.,
catalogue reference numbers, manufacturer
etc.
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Measured Quantities
• Relate to the work section and consists of
precise measurements and description of
work. Items are quantified according to the
nature of the work ie metres run, metres
square etc
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Provisional Quantities
• Covers items in the BOQ for work that was not
known at the time of tender, ie rock, water
etc.
• Would be measured or omitted on
completion.
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Prime Cost Sums (PC Sums)
• A sum allocated for work to be done or
materials delivered by nominated
subcontractors, suppliers, the amount being
provided by them.
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Provisional Sums
• Not to be confused with provisional
quantities.
• This relates to a sum which is provided for in
circumstance which cannot be entirely
foreseen, but which it is known is likely to be
required.
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Pre-contract Stages
•
•
•
Inception
Feasibility
Scheme Design
– Outline proposals
– Detailed design
•
•
•
Production information
Bills of quantities
Tender action
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Tender action
• Architect will select method of tendering to be used
and produce all the tender documents.
• Documents sent to builders so that they can estimate
the price for which they are prepared to do the work.
• The tenders must be submitted by a specified time and
date.
• On the specified date the tenders will be opened and
the Architect / Client will select the builder that they
think most suitable, who then becomes the Contractor.
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