INTRODUCTION TO QUANTITY SURVEYING PDF

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DAR 1205 QUANTITY SURVEYING I Introduction:   History and Development of Quantity Surveying.  Personnel in Building Contracts and Their Responsibilities.  Functions of a Quantity Surveyor in Building Contracts. Use of Dimension Paper; Setting out, order of Dimensions, side notes, waste  calcula...

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INTRODUCTION TO QUANTITY SURVEYING laki emmanuel nelson

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DAR 1205 QUANTITY SURVEYING I Introduction:    

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History and Development of Quantity Surveying. Personnel in Building Contracts and Their Responsibilities. Functions of a Quantity Surveyor in Building Contracts. Use of Dimension Paper; Setting out, order of Dimensions, side notes, waste calculations and use of schedules Use of Bill of Quantities. Use of Standard Method of Measurement.

1.01 QUANTITY SURVEYING This is the quantification/estimation of works for a construction project and costing them. 1.02 A QUANTITY SURVEYOR This is a trained person in construction works’ quantification and costing and contract procedures. 1.03 ROLES OF A QUANTITY SURVEYOR  

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Prepares the bills of quantities Approximates the estimate of costing in every stages of the formation of the building project. He plans for the client so that he gets the best value of his/her money for any construction projects to be carried out ( cost planning) Examines, the tenders and prices of the BOQ and reports his findings to the architect Negotiates with the contractor the desired amount to pay to him for the contract Advices the client on the selection of the contracton Values work in progress and recommends payment to be made to the contractor.( valuation) Advices on financial aspects of the contract valuation( Cost advise) Prepares the final account when the contractor finishes the work He prepares the tender documents Advises on the form of contract

1.04 ESSENTIALS OF A GOOD QUANTITY SURVEYOR 

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He must be able to describe clearly, fully and precisely the requirement of the architect and arrange the BOQ in such a way that the works can be quickly and accurately cost. Must be able to write in clear technical language that will not be miss-understood

1|Quantity Surveying notes prepared By Mr. Zzigwa Marvin Email:[email protected]; Tel No 0775984782

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Must have sound knowledge of the building materials, construction techniques and of customs prevailing in the industry Must be able to accurately interpret construction drawings Must be careful and accurate in making calculations Must have a systematic and orderly mind to be able to visualize the drawings and details Must have good knowledge of the construction prices ( to be able to offer cost advise) Must have ample knowledge of the law of contract Must be competent to conveyor to the person who is to price the BOQ, the quantity and quality of the materials required and the nature of labour to be applied during the construction of the structure.

2.0 TYPES OF BUILDING CONTRACTS (WITH AND WITHOUT QUANTITIES) 2.1.0 Contracts without Quantities These contracts are normally restricted to minor works and the contract documents comprise of drawings, specifications and form of agreement.  Drawings include plans, elevations, sections and large scale details of proposed work.  The specification is prepared by the architect to supplement the drawings. In the specification, the mixes of concrete, types of bricks and quantities of any other work are stated and methods of work are normally stated.  A form of agreement is a legal agreement signed by both parties which states the builder’s contract to erect the structure in accordance with the drawings and specifications and the client agrees for his part to pay the contract sum.

Formally contractors would simply study the drawings and specifications and would rely on past data to quote the contract sum. As competition grew keener, it became difficult to use it. It became necessary to take off measurement and prepare quantities of work involved. Applying prices to these quantities, one would come up with the total estimate of the work. The quantities prepared were not only those of materials but specific elements in the structure like walls, roof, e.t.c. Examples 2.1.1 Cost Based Contracts (Happens under negotiated tenders) A cost REIMBURSEMENT/ COST PLUS CONTRACTS Here a contractor agrees that his expenditure on labour and materials will be met by the client (thus cost reimbursed) on top of which he will charge a fee on an agreed basis, to cover his profits and overheads This type of contract encourages wastes and extravagancy 2|Quantity Surveying notes prepared By Mr. Zzigwa Marvin Email:[email protected]; Tel No 0775984782

Reasons for their use i. ii. iii. iv. v.

Emergency on repair works where time is no available to allow the traditional process to be used. When new technology is being used Contracts where high quality work is required Contracts where cost is not important but where the client wants control over the methods of executing of projects Where a special relationship exists between the employer and the building contractor

Main Benefits i. ii. iii. iv. v.

Great flexibility of design changes Easy client participation Permits earlier Start of the project Low risks to the contractor Full knowledge of the costs

Dis-advantages i. ii. iii. iv. v.

The client cannot forecast the total cost of the project with high degree of certainity No incentive for the contractor to reduce costs Encourages wastes and extravagancy High caliber client management skills are required Difficulty in evaluation of competitive tenders

Types a) Cost Plus Percentage In this type of contract, the contractor charges a certain agreed percentage on the amount spent on the materials, labour and plants, for his profits and overheads The major disadvantage is that the greater the cost, the higher the fee to the contractor. 1) Cost Plus Fixed fee In this form the contract, the contractor is paid the actual cost of work plus a fixed lump-sum, which has been previously agreed upon and which does not fluctuate with the cost of the job 2) Cost Plus Fluctuating Fee Here the contractor is paid the actual cost of work plus a few, with the amount of the fee being determined by the reference to the allowable cost of works, the lower the actual cost of the works, the greater will be the fee that the contractor receives. It encourages the contractor to carry out the work as quickly and cheaply as possible 3|Quantity Surveying notes prepared By Mr. Zzigwa Marvin Email:[email protected]; Tel No 0775984782

2.1.2

Schedule contracts

Types a) Schedule of rates Here, expected items of work to be done are listed (without their quantities) for the contractor to price. It is used where it is not possible to pre-determine the nature and full extent of the proposed work. It is difficult for the contractors to price the schedule realistically in absence of quantities. It is commonly used on repair works, agent works, etc. b) Schedule of materials This is alternative to the schedule of rates. Here a list of all materials to be used for the expected works is given and the contractor attaches the price on each. The contractor may then add a percentage of the total sum for the materials for hos labour, profit and overheads. (Cost for running the contract) 2.1.3 Package Deal/ Design and Construct/ All-In Contract With this type of contract, the employer gives his requirement in broad outline to the contractor who submit full detail of the design, construction and cost of the project It is suitable for specialized work The contractor can commit himself to a price and completion date at an early stage In case of competitive tendering, prices are based on different designs which makes evaluation hard 2.1.4 Direct labour The client employs labour, buys materials and engages sub-contractors on the items that require so. The client does all the organization of the work and bears all the risks. The client may employ a technical adviser 2.1.3 Lump- Sum Contracts In a lump sum fixed price contract, the contractor undertakes to carry-out the contract work for a fixed sum of money. The details of the contract are normally shown on the drawings and described in the specifications but no BOQ is supplied. It is often used where: The job is reasonably certain in nature and small in extent 2.2.0 Contracts with quantities These contracts are normally prepared for major works and they are based on BoQ. The BoQs are prepared by the quantity surveyor on behalf of the client. Several copies of BoQs are repaired and sent out to the contractors who are interested in doing the work to enter in their prices or rate for the execution of the work. When the contract is signed, the BoQ and prices become part of the contract agreement and will be used in preparation of the final accountability and in the settlement of variations. The revision 4|Quantity Surveying notes prepared By Mr. Zzigwa Marvin Email:[email protected]; Tel No 0775984782

of BoQ leads to accurate tendering as all those tendering have identical conditions on which to work and this considerably reduces the cost of estimating. Examples 2.2.1 Price In Advance Under this type of contract, the contractor agrees to carry-out his obligation for the sum of money agreed upon in advance. The contractor is responsible for all the labour, materials, and plants. Etc. This type of contract gives the client almost no control over the detail of methods of neither work programming nor expenditure. The contractor bears all the risk Types a) Contracts based on BOQ This is generally the soundest form of contract. It is suitable for all projects, provided all planning and design work has been completed at tender stage. The scheme is designed and a number of contractors are asked to submit in Lumpsum tenders based up on the pricing and totaling of the BOQ prepared on the behalf of the client Standard qualitative and quantitative information enables tenders to be compared on the price alone Is the most common type of contract used for all major construction projects Provides the client with good degree of control over financial aspects of the project It does not provide for contractor participation at the design stage The prices BOQ provides are the basis for valuation of variation 2.2.2 Target Cost Contracts In a target contract a basic fee is quoted as a percentage of the agreed target estimate obtained from a priced bill of quantities. The target estimate may be adjusted for variation in the quantity and design and fluctuations in labour and material costs. The actual fee paid to the contractor is determined by increasing or reducing the basic fee by an agreed percentage of the savings or excess between the actual cost and adjusted target estimate, It discourages wastes There is an incentive to the contractor to complete the work speedily and economically as possible

5|Quantity Surveying notes prepared By Mr. Zzigwa Marvin Email:[email protected]; Tel No 0775984782

3.0.0 TENDERING This is the submission of a quotation. A quotation is a price that a firm charges to offer a good or service. 3.0.1 Taking a decision to tender Against corporate plan, senior managers will take the decision to bid for a specific contract. Decisions are taken; During the pre-selection stage After careful examination of the contract documents After the estimate has been prepared and tender is ready to submit 3.0.2 Factors considered while taking the decision to tender Potential contribution of the contract to the company’s turnover in a particular sector; the overheads recovered and the anticipated profits The likely demands of the contract on the company’s financial resources The company’s resources available e.g the working capital and human resources Type of work The location of the project The type of client Contract deal 3.1.0 Tendering Procedures or Methods / Contract Procurement Mechanisms 3.1.1 Open tendering/contracting The procedure is to advertise in the press inviting any firm that wishes to do so to submit a tender; bid or offer. The advertisement will give an outline detail of the type of work, the scale program and any other key features. Any interested firm applies for the tender documents and there are usually no formalities other than a little fee for the tender documents and discourage those who are not interested in the job or idle curiosity. This system is commonly used by public bodies. e.g. local governments, public services although it is also used by private institutions. It’s usually stated in the advertisement and in the tender document that the employer does not bind himself to the lowest offer as the advertisement does not bid the employer in any way but it is merely an invitation to person or firms to make an offer and any offer made should be unconditionally accepted. Merits It gives a chance of tendering to a firm which wishes to do so. Since there is no restriction, there can be no chance of favouritism. Demerits 6|Quantity Surveying notes prepared By Mr. Zzigwa Marvin Email:[email protected]; Tel No 0775984782

There are a large number of tenders to evaluate hence much time and money wasted. There is normally pressure to accept low tenders. There is a high cost on the contractor’s side as he tenders for very many jobs and wins nothing or only one. There is difficult in selecting the right firm. 3.1.2 Selective tendering/contracting Here the procedure is to select a limited number of firms known to the architect/client and invite them to tender and this procedure is mainly used by private firms or institutions. Selection should be made sufficiently early for firms to be asked whether they will be willing to tender at the required time. The criteria to be employed in drawing up the list of the selective firms will depend to some degree on the character of the project as well as its size, location. Also consider equipment available, standard of workmanship by firms, size of payroll, business record, and number of strikes within the company, financial stability, and real willingness to tender. Merits It’s possible to select the most competent firm. Since tenders are few, there is time and cost saving. Demerits The firms are sometimes overloaded as they may be reluctant to decline some tenders at the time they have a lot of jobs. It breeds/ brings favoritism and corruption. There is always reluctance to strike off incompetent firms from the list. Newly formed firms that are competent cannot tender for the job. There is always higher quotation than obtainable by open tendering as there is less competition. 3.1.3 Single tendering/contracting There may be circumstances in which only one firm will be able to satisfy the criteria for selection. This likely happens when specialist or nominated contractors e.g in installation of lifts, gas pipes works, supply of some selected materials are involved. Merits It is cheap to evaluate the tender. The firms with tested results are employed. Demerits It’s usually expensive as a single contractor tenders. 7|Quantity Surveying notes prepared By Mr. Zzigwa Marvin Email:[email protected]; Tel No 0775984782

It’s somewhat undesirable and perhaps an un health state of affairs and can be embarrassing is un satisfactory tender is received. 3.1.3 Serial tendering/contracting Is a premeditated (deliberate) form of extension and comes essentially into the category of tendering rather than negotiation. It applies where there a series of similar schemes which are to be carried out over a period of time within the same area and permitting the phased utilization of the site organization and plant e.g construction of schools. It is useful for main contracts and can also secure the benefits of the increased size of order and production run for component contract and specialist site installation work which become subcontracts to a series of main contracts. An example is where a contractor is invited to tender for one building e.g a school on the understanding that the successful firm will build several schools at the agreed rate. Merits It encourages keener prices than would project for single project. Experience gained on the earlier project will be useful later on. Demerit Rapid inflation tends to curtail this type of contract 3.1.4 Negotiated tender/contracting This is usually used for construction of a very difficult nature of work, where the magnitude of the contract may be unknown at first or where early completion is most important, or where continuation or repetition of an existing contract is considered desirable. For this contract, there is usually no time to wait for drawings and BoQ to be prepared. One firm is selected and negotiated with. Merits It’s time saving as no documents/ drawings are prepared. It offers a more rational price basis for the contracts perhaps stimulate design improvement. Demerits It’s hard to satisfy the test of the public accountability. Suffers from higher cost due to lack of competition. 3.1.5 Prequalification contracting Is where a selection of capable firms takes place before submission of the tenders or quotations. Merits 8|Quantity Surveying notes prepared By Mr. Zzigwa Marvin Email:[email protected]; Tel No 0775984782

The same as for selective tendering. Demerits The same as for selective tendering except leaving out of new firms. 4.0 Tender Documents Vs Contractual Documents 4.1.0 Biding/Tender DOCUMENT Is a formal document issued at a fee by the client to the interested contractors prepared by the clients professional technical advisors which contains all relevant information about the clients project, that needs to be brought to the knowledge of the contractor with reference to the contracting procedures, terms of contracts and work specifications . It contains general conditions of the contract, draft contracts for work, form of bid, technical specifications, and bill of quantities, drawings, forms of item/final certificates invitation to bid and instructions of bidders.

4.1.1 General conditions These are laws defining the relationships in the contract (I.e. Between the client and the contractor and other parties) and how work will be executed. 4.1.2 Forms of bid /contractor s bid It is the document signed by the contractor in which he offers to execute the work as described by the drawings and specifications and accepting all the conditions and provisions of the contract as described in the bidding document for a given sum of money, the discussion is left to the client to accept or reject the offer. 4.1.3 Instruction to tender This will include; Place, date, time by which tenders must be returned. Methods of dealing with queries. How qualified tenders will be dealt with. Provision for site visits. Documents to be submitted with a tender. Methods of dealing with errors 4.1.4 Conditions of contract These do two things: Sets out the contractual responsibilities and liabilities. Establishes the administrative arrangement. 4.1.5 Draft contract for work (Form of document) 9|Quantity Surveying notes prepared By Mr. Zzigwa Marvin Email:[email protected]; Tel No 0775984782

It is a legal document signed by both the employer and the contractor which states the contractor is to undertake the works in accordance with the drawings and the specifications and the clients contracts to pay him the contract sum in consideration. 4.1.6 Technical specifications

This is the part of the bidding document drawn up by the architect to suppliment the drawings which clearly describe in detailed manner. i.

The quantity and standard of materials to be used ( and where applicable the possible supplier ) ii. Handling and treatment of materials iii. Nature of fixing ,assembling and installation of any materials and service iv. Quality of work manship required v. Any other special treatment or handling of material that needs to be brought to the attention of the contractor. 4.1.6 Drawings Are plans, elevati...