Pre-Contract Procedures

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Transcript Pre-Contract Procedures

Pre-Contract Procedures

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Pre-contract Stages

• • • • • • Inception Feasibility – Scheme Design Outline proposals – Detailed design Production information Bills of quantities Tender action constructionsite

Inception

• • • What is the purpose of the building Why it needs to be build What is to be built constructionsite

• • 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

• • • • • • Inception Feasibility – Scheme Design Outline proposals – Detailed design Production information Bills of quantities Tender action constructionsite

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 constructionsite

• • 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 constructionsite

Considerations

• • • • • • •

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. constructionsite

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 constructionsite

Methods of Assessing Construction Costs

• • • • Elemental Cost Analysis Cost per unit area Approximate Estimating Bills of Approximate Quantities constructionsite

Elemental Cost Analysis

• • 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. constructionsite

Pre-contract Stages

• • • • • • Inception Feasibility – Scheme Design Outline proposals – Detailed design Production information Bills of quantities Tender action constructionsite

Scheme Design

• Produced from the Design Brief given to the architect by the client constructionsite

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

• Objectives must be set by the study with regard to: The function of the building: 1. The persons using the building 2. Budgetary constraints 3. Life cycle of the building 4. Site considerations. constructionsite

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 constructionsite

• • Outline Detail

Scheme design

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Pre-contract Stages

• • • • • • Inception Feasibility – Scheme Design Outline proposals – Detailed design Production information Bills of quantities Tender action constructionsite

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 constructionsite

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

• • • • • • • Form of Tender Preliminaries Preambles Measured work section Dayworks Prime cost and Provisional sums Final summary constructionsite

Preliminaries

• • • Referred to as Prelims, these are found at the commencement of the BofQ.

General items Provides extra information to contractors constructionsite

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 constructionsite

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. constructionsite

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 constructionsite

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. constructionsite