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QUANTITY SURVEYING

Table of Contents 1. Introduction 2. Importance of Quantity Surveying 3. Requirements and types of estimation 4. Estimation of Buildings 5. Specifications and Contracts 6. Valuation 7. References 8. Sources QUANTITY SURVEYING Quantity Surveying is used in estimation, planning and manage the construction projects costs. It involves planning of cost, cost estimation, feasibility studies, value engineering, cost benefit analysis, life cycle costing and valuation. Optimum use of resources (materials, manpower, money) is the main objective of a quantity surveyor. He must have the latest information of market and tools to help in planning and managing resources efficiently. Data needed to prepare Quantity Survey: Drawings Complete drawings (i.e. plans, elevations, sections and other details) of the building or work are required. Specifications Data like type, nature and quality of work, its quality, proportions, required materials and method of preparation are required. Rate The rate of construction materials, different works, wages of different labour and transportation costs helps in estimating work cost. Total Finished Work We can calculate quantities from observing materials used and work done in the process. – We can calculate quantities in following way: Quantity = Length × Width × Height , Quantity = Area of cross-section × Length, Quantity = Length × Width, Quantity = Length. Quantity = Number of Units. Quantity = Weight. Importance of Quantity Surveying 1. Quantity survey helps to estimate the expenses of construction before it actually starts. It covers labour charges, cost of tools and plants, transportation costs, establishment and supervision charges, materials costs, water charges, taxes and contractor’s profit, etc. It makes inviting tenders for the works and arranging contract for a complete project convenient. 2. Quantity survey estimates the quantities of the various materials required and the labour to successfully complete the project within determined time and budget. 3. We should check the works done by contractors during and after the execution. Also the contractor is paid for each completed piece of work . 4. The knowledge of quantity survey helps to provide useful advice to clients on: (i) Estimating properties’s valuation for sale, purchase and mortgage etc. (ii) Fixing standard rent. (iii) For the process of resolving disputes by referring to a third party. (iv) For insurance purpose and claiming for building damages. ESTIMATION Estimation is calculation of the quantities and the expected expenditure on a project. We need the follwing to prepare estimate:  Drawings of elevation, ground plan and sections .  Detailed information about properties of materials & workmanship etc.  Standardised rates schedule for current year. REQUIREMENTS OF ESTIMATION AND COSTING  We can easily predict the expenditure and work feasibility.  It approximates how much time will it take to complete work.  It is useful for inviting tenders and to arrange contract.  It control the expenditure while executing work.  Estimate ensures if the expenditure is within the funding of project TYPES OF ESTIMATES  Approximate Estimate This finds out an approximate cost quickly. It gives a rough figure of the proposed project cost. This estimate helps the client and sanctioning authority to make decision of the administrative approval. The approximate cost is prepared by comparing with similar works. We calculate work for a unit area or volume and multiply it with total quantity to find cost for whole work.  Detailed Estimate After the administratiion gets the approval, this estimate is prepared in detail before inviting tenders. The project is split into various tasks, and later their quantities are calculated. The drawings of the project are used to determine dimensions of the required work.  Quantity Estimates Complete estimate of quantities for all items during the project .  Revised Estimate Prepared if the estimate exceeded by 5% due to the rates being found unavailable or other reasons.  Maintenance Estimate To maintain a structure (road, building, etc.) we estimate quantities and cost of work. PROCESS OF ESTIMATING We prepare detailed estimate and calculate the rate for every work. For estimation we need drawings( plans,elevations ,sections,etc), specifications and rates. RATES Unit rates are used for estimation. We need the rates of different construction materials, the transport materials costs and the labour wages, carpenters, masons,etc. ESTIMATION FOR BUILDINGS The quantities of foundation concrete, earthwork in excavation, brick work in plinth and foundation, brick work in the super-structure etc. can be estimated by three methods:  Center Line Method Firstly we calculate the centre line length of walls, then multiply the centre line with the breadth and depth of respective item to get the total quantity at any time. For different sections of walls, the centre-line length for each type will be calculated separately. This method is more quick and accurate than the other two methods.  Long Wall and Short Wall Method We centre the longer walls in a building in one direction measured from out to out as long walls and the partition walls in perpendicular to long walls, as short walls . To get the quantity we need the sum of height of the corresponding layer and the lengths of long walls and short walls arc multiplied separately by the breadth. The lengths of long and short walls vary in different layers. We first determine the centre to centre lengths from the plan to calculate the lengths of long walls and short walls. Then the out-to-out length of the long wall can be calculated after adding the half breadth of a wall at each end with centre to centre length. So the length of the short wall measured, in-to-in can be calculated after subtracting half breadth at each end from centre to centre length. . Crossing Method The perimetre of the building is found out and four times the thickness of the wall is substracted from it to obtain the centre-line length. Crossing method is used rarely. Estimation of a Septic Tank Definition of Septic Tank Septic tank is a water-tight chamber made from fiberglass, PVC or plastic, concrete, through which sewage water flows to get recycled. Anaerobic (non-oxygenated) processes and settling reduce organics and solids, but the treatment is only moderately effective. These are a type of on-site sewage facility (OSSF). They can be used in areas having lack of sewerage system, like rural areas. The treated effluent is generally disposed in a septic drain field for more treatment. Components of Septic Tank 1. Inspection Pit: A hole in the ground, lined with site built or manufactured sides that receive Waste-water from house or building. The wastewater then flows from inspection pit to septic tank. 2. Septic Tank: It is a buried, watertight container made of concrete ,fiberglass or polyethylene. The wastewater solids settle down as sludge and scum. Solid materials also undergo decomposition. T-shaped outlet and compartments in the tank prevent the scum, and sludge from leaving it and travelling into soak pit. 3. Soak Pit: It is a covered chamber made of porous walls. Water gets slowly soaked into the ground. Previously settled effluent from semi-centralized treatment technology is discharged to the underground chamber. After which it infiltrates into the nearby soil. Components of Septic Tank (Source: http://www.natureclean.com) Earthwork Excavation for Roadway Calculation of Volume There are three methods to calculate earthwork volume depending on land formation types: 1) From cross sections 2) From spot levels: Used for large excavation. 3) From contours: Rough estimates of volume may be made by treatment of the contour lines. Measurement from Cross Sections The cross sectional area along the line is first calculated by standard formulae and the volumes of prismoids between every cross-section are then calculated by following methods: 1) Formulae of Average height method. 2) Formulae of Mean-sectional area method. 3) Formulae of prismoidal method according to Simpson’s one-third rule. Mid-section formulae (or Average Height Method) Depth section (1) = d1 (difference between FL & GL) Depth section (2) = d2 (difference between FL & GL) Average depth, davg = (d1 + d2)/2 Section Width = b Side slope = 1: s (vertical : horizontal) Area of mid-section, A mid = bdavg + (1/2) sdavg2 + (1/2) sdavg2 A mid = (b+sdavg) x davg Length between two consecutive sections (!&2) = L1-2 Volume of earthwork between these two consecutive sections (1&2), V1-2 = Aavg x L V1-2 = (b+sdavg) x davg x L (may be cut or fill) Trapezoidal Formula (or Mean-Sectional Area Method) Depth section (1) = d1 (difference between GL & FL) Depth section (2) = d2 (difference between GL & FL) Area at end 1, A1 = (b+sd1) x d1 Area at end 2 , A2 = (b+sd2) x d2 Mean sectional area, A mean = (A1+A2)/2 Width of section = b Side slope = 1: s ( vertical : horizontal ) Length between two consecutive sections (1&2) = L Volume of earthwork between these two consecutive sections (1&2), V1-2 = Amean x L V1-2 = A mean x L (may be cut or fill) Prismoidal formula Depth section (1) = d1 (difference between GL & FL) Depth section (2) = d2 (difference between GL & FL) Area at end 1, A1 = (b+sd1) x d1 Area at end 2, A2 = (b+sd2) x d2 Mean sectional area, Amean = (A1+A2)/2 Width of section = b Side slope = 1: s ( vertical : horizontal ) Length between two consecutive sections (1&2) = L Volume of earthwork between these two consecutive sections (1&2), V1-2 = (A1+ 4Am + A2)/6 x L Estimation of a Retaining Wall Retaining wall A retaining wall resists the lateral pressure of soil. It is designed for that specific purpose. It protects embankment of roads, hills etc. Types of Retaining wall 1. Gravity 2. Cantilever 3. Sheet piling 4. Anchored 5. Counterfort Figure: Typical Retaining wall Estimation of Culvert Culvert is a small bridge type structure which carries water from one side to another. It’s covered with structural material perimetre and has an embankment. In general they are of maximum 3 spans. Use of Culvert 1. Where the roadway is intersected by natural streams. 2. For passing surface drainage. 3. Bottom of depression where no natural water course. Different Types of Culvert 1. Arch Culvert: It is a low profile culvert. It can be installed without the causeway getting disturbed as it will span over the entire drainage width. Construction materials used are stone masonry, metalworks or RCC. They are easy to install without using costly water diversions. It is found in various shapes like, semi-circular arch, elliptical arch, and concrete box. They are faster to install when compared to traditional box culverts. Figure: Arch Culverts (https://qph.ec.quoracdn.net) 2. Slab Culvert: A slab culvert is made of RCC slab. These overcome problems of Masonry arches like, difficulty in centreing, shuttering, less life, more chance of cracks and more dead load. The slabs are either made from RCC or stones. Figure 4.3: Slab Culverts (http://www.lefiltredumonde.com) 3. Pipe culvert: These are available in shapes such as circular, elliptical and pipe arches. Circular pipes are the most common while other shapes are used depending on site conditions and constraints at the job site. Their prices are very competitive, and they are very easy to install. The culvert is selected based on hydraulic design to maximize performance and suitability. It is popular in urban areas andeasily manages storm sewer systems. Figure 4.3: Pipe Culverts (https://www.civilgeo.com) 4. Box culvert: Box culverts have a concrete floor so that water flows smoothly. RCC are most common material to construct these culverts. Some box culverts can be built using composite structures and are great for large water flow or when we need to change water direction. The top of the box culvert is also the roadway surface giving multiple uses. Figure 4.4: Box Culverts (http://www.hudsoncivil.com.au) 5. Steel girder culvert: A steel girder culvert has two steel girders running side-by-side to support the main rail path. This type of culvert can only be seen in railways. Two main girders are laid just below the rails. Wooden sleepers are provided between these girders and the rails. These are also called open deck culverts. Figure 4.5: Steel Girder Culverts (http://2.bp.blogspot.com) 6. Scupper: A scupper is an opening in the side walls of an open-air structure.It is constructed for draining water purpose. They are usually placed near ground level, and allow rain or liquids to flow off the side of the open-air structure, instead of pooling within the walls. Figure 4.6: Scuppers (http://www.nzdl.org, https://i.ytimg.com) Slab Culvert Slab culvert is one of the most commonly used culvert in Bangladesh. Bangladesh has 3991 box culverts out of 18257 total culverts accounting for 22%. (http://www.rthd.gov.bd/bridge_maintenance.php). Advantages of Slab Culvert a) Simple in construction b) Suits best for feeble sub grade. c) Even load distribution over large area. Components of RCC slab culvert 1. Abutment a) Supports the bridge deck. b) Retains the embankment. c) Connects the approach road to bridge deck. 2. Wing-Wall a) Acts as anchor. b) Provides smooth movement for water. c) Prevents spilling of embankment dam 3. Slab or deck a) Carries load of vehicles. Figure 4.7: Abutment and Wing wall (oldcastleprecast-yut3re1sojoa.netdna-ssl.com) FIXING RATE PER UNIT TIME It includes:  Quantity of materials and their costs: The cost includes first cost, transportation and insurance charges.  Labour costs: Number of labourers multiplied by their daily wages per unit work.  Equipment costs : Some of the works need special machinery and tools. We spend 1-2 % of total estimate cost over this purpose.  Overhead charges: We spend 4% of estimate cost for office rent, equipment depreciation, salaries of staff people and lighting. WAYS TO PREPARE APPROXIMATE ESTIMATE Approximate estimate is calculated from the practical knowledge and cost of similar works . 5 to 10% is allowed for contingencies. We can use the following methods :  Plinth area method We multiply plinth area with its rate to calculate the construction cost. Multiplying length and breadth (outer dimensions of building) gives area. The following areas are included while calculating the plinth area of building as per IS 3861-1966. Types of Estimates (i) Wall area at floor level. (ii) Internal shafts of sanitary installations under 2 m2 . (iii) Non-cantilever Porch.  Cubical Contents Method It is more accurate. The cost of a structure is calculated from Local Cubic Rate multiplied with total cubical volume. The dimensions are measured out to out of walls excluding the plinth off set. The cost of building= volume of buildings x rate/ unit volume. Bill of Quantities A building owner wants to know the cost of his building before placing the order. In order to find out the cost of a building, detailed quantities have to be worked out keeping with the requirement of the Standard Method of measurement and price by the Builder. These quantities when collected together into a bill, form a bill of quantities. The advantages of a bill of quantities are as follows: (1) It forms a common ground for competitive tendering which is essential to obtain a reasonable value to consider. (2) It forms in itself a range of rates for measured work which can be used in the contract for evaluating variations and final account. (3) It is useful for building operations for the completing interim payments. The following points are important for producing good bill of quantities: (1) Deep knowledge of building construction helps in correct interpretation of the drawings. (2) Accuracy and neatness in setting out and measuring. (3) A thorough knowledge to write concise description and clear language to translate the drawings into words. SPECIFICATION A Specification is a special description of a subject. An engineering specification contains details of all working labourers and material. It is a short description of different portions of work specifying materials, proportions, qualities, etc. It can be classified as follows: a) General Specifications: This gives the nature, quality, class and work and materials in general terms to be used in work. b) Detailed Specifications: It describe in detail various items of work ,like quantity and quality of materials, their ratios, preparation method and labour. Detailed Specifications Of Excavations Scope It covers:  excavation of trenches, foundations, pits and over areas, in every soil, hard and soft rock,  protection of underground utilities,like water supply system, electricity cables and shoring  refilling around the foundation and the plinth with some excavated earth materials  disposing off the surplus earth materials within specified lead  finishing the surface to proper levels,slopes and camber etc. Site Clearance:  The area is cleared of all encroachments, loose stones ,rank ,vegetation, shrubs, grass and bushes  Up to 150 metres outside area’s parametre is cleared.  This work is merged with the earthwork item rate without separate payment. Roots and Vegetation clearance:  The roots of vegetation will be removed to 60 cm below ground level or 30 cm below formation level whichever is lower and the depressions created will be filled up with leveled and rammed earth.  Materials obtained from the work-site will belonf to the Government of India and the resourceful materials will be conveyed & stacked properly. Profile Making and setting out: Pillars of concrete are erected for the purpose of benchmarking and for work execution. Essential profiles with bamboos, Burjis, strings or pegs show rightt formation levels before the work starts. The contractor supplies workers and goods for making profiles and setting out. The Department shows reference points on grid co-ordinates. The contractor sets out centre lines according to the drawings and installs necessary reference marks. Excavation: The ground levels will be taken at 5 to 15 metres gaps in uniformly sloped ground and near to local mounds, pits, or undulations. The ground levels will be recorded in field books and plotted on plans before starting the earthwork. The Contractor will supply the labour required for taking levels. The item in the schedule of quantities will specify the excavation in trenches. For this purpose, the excavation for any depth in trenches for foundation not exceeding 1.5m in width or 10sqm. on plan will be described as excavation in foundation trenches. Excavation exceeding 1.5m in width as well as 10sqm. on plan (excluding trenches for pipes, cables etc.) and exceeding 30cm in depth will be described as excavation over areas. Excavation exceeding 1.5m in width as well as 10sqm. on plan but not exceeding 30cm.in depth will be described as surface Excavation. Classification of Earth work: The earthwork will be classified under the following: All types of Soils, Murrum, Boulders: This includes earth, murrum, top deposits of agricultural soil, reclaimed soil, clay, sand or any combination thereof ad soft and hard murrum, shingle etc. which is loose enough to be removed with spadies, shovel and pick axes. Boulders not more than 0.03 cm. in volume found during the course of excavation will also fall under this classification. Excavation in Soft Rock: This will include all materials which are rock or hard conglomerate, all decomposed weathered rock, highly fissured rock, old masonry, boulders bigger than 0.03 cm, in volume but not bigger than 0.5 cm. and other varieties of soft rock which can be removed only with pick axes, crow bars, wedges and hammers with some difficulty. Excavation in Hard Rock : This includes soft rock, occurring in masses, boulders having approximate volume more than 0.5 cm, plain or reinforced cement concrete, which can be removed by chiseling and wedging where blasting cannot be permitted. Excavation in Hard Rock by Chiseling and Wedging: The excavation will be done by chiseling and wedging where blasting is not permitted . Note: All the excavated hard rock obtained will be stacked properly and neatly within the specified lead Excavation Cutting will be done from top to bottom. Under cutting or under pining is not desired. The sides and bottom will be dressed to proper slopes, camber, level, steps, etc. by ramming and removing high spots. Excavation will be mudmat concrete wide and as deep as indicated in drawing.The hollows will be filled up over cut at specified level with 1:4:8 cement concrete for soils and with 1:2:4 cement concrete for soft and hard rock if the depth is more than specified. After the excavation is completed dimensions, the kind of foundation materials, levels and measurements will also be recorded. Shoring: Excavation of slopes to prevent soil from falling in by maintaining, bracing, fixing and removing of shorting,etc will be included in rate of excavation. Shoring with massive loads and traffic, will be of enough strength to ensure safety from slips, resist the pressure, and to prevent damage to property and injury to people.Payments will not be done for removal of the slipped earth. De-watering: Pumping out water accmulated in the excavation because of springs, seepage, rain during the progress of R.C. footings, mud mat concrete and shuttering will be included in the rates. Water is discharged carefully from the foundations to keep it nuisance-free. Disposal of Excavated Materials: Antiques: Coins, relics of antiquity, fossils or other articles of archeological importance will be the property of the Government of India and will be delivered to the Engineer-in-charge Resourceful Materials: Excavated materials will be arranged in regular stacks and will belong to the Government of India. Excavated materials from foundation are placed closer than 3m from the outer edge. Suitable material for backfilling will be stacked in a place without obstructing free movement of materials, workers and vehicles or encroachment on the constructional area. It will be used to backfill the structure to original ground level or as per the plan. Unused materials will be disposed off, leveled and compacted. The site will be left clean of all debris. Backfilling : The excavated material used for backfilling will be brought from the area with temporary deposits. Extra earth available will be used for backfilling for other buildings. All timber shoring and form work left in the pits ,trenches, floors etc. will be cleared out. All the space between foundation masonry and the sides of excavation will be backfilled to the original surface in layers within 150mm thickness, watered and rammered to 90% of the consolidation. Areas adjacent to walls and columns will be tamped by hand rammer. The backfill will be even, free from any lumps, shingle, stones, clods, salts, or other rottable organic materials. To establish consolidation, two tests per 50 sqm will be carried out at specified rates. Filling in Under Floors and Plinth: The earth,gravel and sand suitable to be filled under floors, will be brought to site from trusted locations and sources. Earth Filling: The earth, soft murrum will be filled up in 15 cm deep layers. Each layer will be watered well and consolidated by hand or mechanical tampers to achieve the required density. Sand filling: Gravel will be of approved qualityand single washed. The size varies from 12mm to 20mm. It will be uniformly blend with soil and sand to obtain compact filling. Gravel will be filled in specific thickness and will be watered and rammed properly. Sand will be clean, medium grained and free from impurities. The filled sand will be flooded with water for 24hrs to ensure maximum consolidation. Lift and Lead: Lead: To measure lead, the excavated area will be divided in blocks. For each block, the distance between centre lines will be taken as the leads. It will be measured by the shortest straight line route on the plan. Lift: It is measured from ground level. Extra lift will be measured in units of 1.5m. All excavation will be measured in 1.5 m units stating the commencing level. It’s not applicable when no lift is involved like in hill side cutting. Measurement modes: Excavation in areas more than 30cm deep will be measured net. The dimensions will be reckoned on the horizontal area of the excavations for the payment will be reckoned on the horizontal area of the excavation at the base for foundations of the walls, columns, footings, rafts or other foundations, multiplied by the mean depth from the surface of ground determined by levels. Excavation less deeper than 30cm will be measured as surface excavation on square metre basis and will mention the average depth of excavation. Reasonable working space will be allowed in execution and considered for payment for underground water tank, sump septic tank etc. Where direct measurements of rock excavation are not possible, volume of rock can be calculated on the basis of length, breadth, and depth of stacks . The net volume will be calculated by reducing it by 40% considering the voids. To find out net quantity of soil to be paid, 20% will be reduced. The rate will include cost of all plants, tools, explosives, dewatering at various stages, shoring, labour and materials . The rate for excavation belongs to excavated materials, picking of stacked articles, conveying it to the place of final backfill, compressing to desired proctor density etc. Quantity of filling is measured and paid in cubic metres up to two decimal places. The rate also include the required extra quantity of excavation involved outside the plan dimensions of the work. If the measurement by levels of site is decided, before starting the work and after completing it, then the quantity of work done will be computed based on these levels. The volume of earth work will be calculated according to Simpson’s formula. SOLING WORK UNDER FLOORS AND IN FOUNDATIONS: Rubble Stone Soling: The rubble stone is a granite, basalt or other locally available stone. It is hard and durable, free from defects and of desired size. Preparing Surface: The bed is cleared of all loose substances, watered, leveled and compacted before laying rubble soling. Pipe trenches will be done before the soling starts. Labour work: The full height stones are laid to have largest area bases and will rest on the sub-grade. Soling is laid in one layer of dimensions 230mm with 150mm depth with 25mm tolerance. After the stones are packed properly in position, the interstices are filled with quarry spoils and stone chips. Spreading of spoils and stone chips is not allowed. The entire surface is examined and will be knocked off by a hammer. All interstices are filled with murrum. Excess murrum will be removed if found over the surfaces. The surfaces are then watered and consolidated with heavy wooden tampers and rammers. After compaction, required level is given. The contractor takes adequate care while laying and compacting the rubble soling to ensure that concrete surfaces are not damaged. Measurement Modes: The quoted rate will be measured per square metre for the soling of desired thickness. The length will be measured up to two decimal places of a metre . The rate will include materials’ costs, labour, transport charges etc. The rate will also include the cost to prepare surface, watering, consolidation etc. REINFORCED CONCRETE AND OTHER WORKS: It covers the requirements for concrete jobs and the use of on-site production facilities. This also covers the transportation of concrete. It is moved from the mixer to the place where final deposit, placing, consolidation, curing, protecting, repairing and finishing of concrete takes place. Cement Concrete (Plain and Reinforced): The quality of materials, manufacturing method and transportation will vary as per the specifications. The Engineer-in-charge can inspect the procurement layout, sources of materials, their storage, the concrete batching, mixing equipments and the quality control system Materials required for Standard Concrete: The ingredients are of standard type Portland cement, clean sand, natural coarse aggregate, clean water, ice and admixtures called for as per the schedule of quantities. Cement : Cement to be used is ordinary Portland cement. Ordinary Portland cement (OPC) 43 grade of reputed brands like Ultratech, ACC, Coramendel or some other brands are used on the work. Cement in bulk are stored in silos to protect from dampness and contamination. Cement bags are stored in a dry enclosed shed, insulated from the floor and away from the outer walls. Damaged or partly set cement is not permitted and will be removed from the site. Consignments in cement are stored as much received and are consumed in the order of their delivery. Contractor establishes testing labs at work-site with qualified staff. Every consignment carries test certificate indicating lot No etc. Sample is taken for each lot and sent to Material Testing Lab for detailed analysis. Cement stored for a period of 90 days or longer is retested before use in work. Aggregates: These are fine and coarse inert materials used in the manufacture of concrete. Fine Aggregate passes through 4.75 mm I.S. sieve. Coarse Aggregate is retained on 4.75 mm I.S. sieve. Aggregate consists of natural sand, crushed stone and gravel and is chemically inert, strong, hard, curable against weathering, of limited porosity and free from corrosive materials. The grading of aggregates ensures a dense concrete. Sampling and Testing: Sampling of the aggregates for mix design and determination of suitability will be taken and delivered to the lab. Record of tests determinines suitability of the proposed aggregate. Storage of aggregates: All coarse and fine aggregates will be stacked separately in stock piles to avoid inter mixing. Rakers will be used for lifting the coarse aggregate from stock piles. Coarse aggregate will be piled in layers under 1 metre height to avoid segregation. Each layer will cover the entire area of the stock pile. Segregated aggregates will be rejected. Specific Gravity: Aggregates with a specific gravity above 2.6 can be used without special permission. Fine Aggregate: Fine aggregate will consist of crushed sand conforming to IS 383. The sand will be clean, sharp, hard, strong and durable and will be free from dust, vegetable substances, adherent coating, clay, alkali, organic matter mica, salt or other organic substances to avoid setting qualities, strength and durability of concrete. Screening and Washing: Sand will be prepared to remove all foreign matter while separating the sand grains. Sand with silt content more than 3 percent will not be permitted unless washed and silt content is brought within 3% by weight. GRADATION: Where the grading falls outside the limits of grading zone of sieves, other than 600 micron sieve, it will be regarded as falling within that grading zone. This tolerance will not be applied to percentage passing the 600 micron sieve. Fine aggregates conforming to Grading zone IV will not be used unless mix designs and preliminary tests are well suited for producing concrete of specified strength and workability. Fineness Modulus: The sand will have a fineness modulus between 2.2 and 3.2 which is determined by adding the cumulative percentages retained on the following IS sieve sizes (4.75 mm, 2.36 mm, 1.18mm, 600 micron, 300 micron and 150 micron) and dividing the sum by 100. Coarse Aggregate: This will consist of crushed stone and gravel, and will be clean and free from elongated, flaky or laminated pieces, adhering coatings, clay lumps, coal residue, clinkers, sag, alkali, mica, organic matter. The coarse aggregate and fine aggregate will be tested regularly. Screening and Washing: Crushed rock will be screened and washed for the removal of dirt and dust coating. Grading: Coarse aggregates will be either single or graded in both the cases. The grading will be within the following limits: Foreign Material Limitations: The percentages of deleterious substances in the coarse aggregate delivered to the mixer will not exceed the following. Water: The suitability of water for making concrete will be ascertained by the compressive strength and initial setting time test. The samples will not receive any treatment before testing other than that envisaged in the regular supply of water proposed for use in concrete. The sample will be stored in a clean container previously rinsed out with similar water. Average 28 days compressive strength of at least three 150mm concrete cubes prepared with water proposed to be used will not be less than 90% of the average strength of three similar concrete cubes. The initial setting time of test block made with the appropriate test cement and the water proposed to be used will not be less than 30 minutes and will not differ by more than 30 minutes from the initial setting time of control test block prepared with the appropriate test cement and distilled water. Water may not be used it it has an excess of acid, alkali, sugar or salt. Limits of acidity: To neutralize 200ml sample of water, using phenolphthalein as an indicator, it should not require more than 2ml of 0.1 normal NaOH. Limits of alkalinity: To neutralize 200ml sample of water, using methyl orange as an indicator, it should not require more than 10ml of 0.1 normal HCL. Beam and Lintel: Beam will be measured from face to face of the columns, walls, cross beams and haunches. The depth of the beams will be measured from the top of the slab to the bottom of the beam. The beams and lintels with narrow width will be measured as beams and lintels only. I) Slab: The length and breadth of slab laid to correct thickness will be measured between beams, walls ad columns. II) Chajjas, Facias, Fins ad Mullions: a. Chajjas will be measured net from supporting faces upto the edges of chajjas without any facia. b. Facia will be measured full excluding chajja thickness. c. End fins will be measured full. d. Intermediate fins, mullions will be measured between chajjs or other supporting structural members. e. Parapets will be measured from top of chajja. III) Staircase: The concrete in all members of staircase like waist slabs, steps, cantilever steps, stringer beams etc. will be measured for their length, breadth ad depth, limiting dimensions to those specified on drawings. No deductions will be made for embedded plugs, pockets. Rates: The rate will include the cost of all materials, labour, transport, tools and plants and all the operations mentioned, including the cost of form work and reinforcement. The rates also will include the cost of testing material, mix design; cube test and allied incidental expenses. The reinforcement steel used in the works will be measured and paid for separately. FORM WORK The form work will consist of shores, bracings, sides of beams and columns, bottom of slabs etc, including ties, anchors, hangers, inserts etc. properly designed and planned for the work. Wedges may be used to facilitate vertical adjustment and dismantling of form work. Design of Form Work: The drawings and calculations for the design of the form work will be submitted before proceeding with work, to the Department. The design will take into account all the loads vertical as well as lateral that the forms will be carrying including live and vibration loadings. Tolerances: Tolerances are specified permissible variation from lines, grade or dimensions given in drawings. Tolerances for R.C. Buildings: i) Variation from the plumb: a) In the line and surfaces of columns, piers, walls and in buttresses: 5 mm per 2.5m, but not more than 25 mm. b) For exposed corner columns and other conspicuous lines of 5 m, maximum 5 mm and for 10 m or more it is 10mm. ii) Variation from the level or from the grades indicated on the drawings. a) In slab soffits, ceilings, beam soffits and in arises. b) In 2.5m (+) 5mm In any bay or 5m maximum (+) 8 mm In 10 or more (+) 15mm c) For exposed lintels, sills, parapets, horizontal grooves and conspicuous lines iii) Variation of the linear building lines from established position in plan and related position of columns, walls and partitions. In any bay or 5m maximum (+) 10 mm In 10 or more (+) 20mm iv) Variation in the sizes ad locations of sleeves, openings in walls and floors except in the case of and for anchor bolts : (+) 5mm v) Variation in cross sectional dimensions of columns and beams and in the thickness of slabs and walls: (+) 10 mm/(-)5mm vi) Footing : a) Variation in dimensions in plan (+) 50mm/(-) 5mm.V- Page 55 of 197 b) Misplacement or eccentricity: 2% of footing within the direction of misplacement but not more than 50mm. c) Reduction in thickness (-) 5% of specified thickness subject to maximum of 50mm. vii) Variation in steps: a) In a flight of stairs Rise (+) 3.0 mm Tread (+) 5.0 mm b) Consecutive steps Rise (+) 1.5 mm Tread (+) 3.0 mm STEEL REINFORCEMENT Steel reinforcement bars will be either plain round mild steel bars grade or medium tensile steel bars or hot rolled mild steel ad medium tensile steel deformed bars or cold twisted steel bars and hot weld strength deformed bars. Wire mesh or fabric will be in accordance with IS 1566. Storage : The reinforcement steel will not be kept in direct contact with ground but stacked on top of an arrangement of timber sleepers or the like. Reinforcement steel will be with cement wash before stacking to prevent scale and rust. Fabricated reinforcement will be carefully stock to prevent damage, distortion, corrosion ad deteriorations. Quality : All steel will be grade I quality. No rolled material will be accepted. Random tests on steel supplied may be performed as per relevant Indian Standards. Steel not clearing the tests will be rejected. All reinforcement will be clean, free from grease, oil, paint, dirt loose mill, scale dust, bituminous materials or any other substances that will destroy or reduce the bond. All rods will be thoroughly cleaned before being fabricated. Pitted and defective rods will not be used. All bars will be rigidly held in position before concreting. No welding of rods to obtain continuity will be allowed. Laps : Laps and splices for reinforcement will be shown in the drawings. Splices, in adjacent bars will be staggered at the locations of all splices. The bars will not be lapped unless the length required exceeds the maximum available length of bars at site. Bending : All bars will be accurately bent according to the sizes and shapes shown on the bar being schedules. They will be bent gradually by machine. Reinforcing bars will not be straightened and rebent in a manner that will injure the materials. Bars containing cracks or splits will be rejected. They will be bent cold if under 25mm in diameter or will be bent hot. Bars incorrectly bent will be used only of ht means used for straightening and rebinding be such as will no injure the material. NO reinforcement bar will be bent when in position in the work without approval, whether or not it is partially embedded in hardened concrete. Bars having links or bends other than those required by design will not be used. Bending at Construction Joints : Where reinforcement bars are bent aside at construction joints and afterwards bent back into their original position, care should be taken to ensure that no time the radius of the bend is less than 4 bar diameters for plain mild steel or 6 bar diameters for deformed bars. Care will also be taken when bending back bars to ensure that the concrete around the bar is not damaged. Fixing / Placing ad Tolerance on Placing : Reinforcement will be accurately fixed by ay approved means maintaining the correct position by the use of blocks, spacer and chairs to prevent displacement during placing and compaction of concrete. Bar intended to be in contact at crossing point will be securely bound together at all such points. The vertical distances required between successive layers of bars in beams or similar members will be maintained by the provision of mild steel spacer bars at such intervals that the main bars do not perceptibly sag between adjacent spacer bars. Tolerance on placing of reinforcement : Unless otherwise specified by the Engineer-in-charge, reinforcement will be placed within the following tolerances: Tolerance in spacing a) For effective depth, 200 mm or less + 10 mm b) For effective depth, more than 200 mm + 15 mm Cover to Reinforcement : The cover will in no case be reduced by more than one third of specified cover or 5mm whichever is less. Unless indicated otherwise on the drawings, clear concrete cover for reinforcement (exclusive of plaster or other decorative finish will be as follows) : a) At each end of reinforcing bar not less than 25 mm, nor less than twice the diameter of such bar. b) For a longitudinal reinforcing bar not less than 25 mm, nor more than 40 mm, nor less than the diameter of such bar. In the case of column of maximum dimensions of 200mm or under, whose reinforcing bars do not exceed 12mm, a cover of 25mm may be used. c) For longitudinal reinforcing bar in a bar, not less than 25 mm nor less than the diameter of such bar and. d) For tensile, compressive, shear, or other reinforcement in a slab, not less than 25mm, nor less than the diameter of such bar and. e) For any other reinforcement not less than 15mm, nor less than the diameter of such bar. f) Increased cover thickness may be provided when surfaces of concrete members are exposed to the action of harmful chemicals and such increase of cover may be between 15mm and 50 mm. g) For reinforced concrete members, totally immersed in sea water the cover will be 40mm, more than specified ( a to e) above. h) For reinforced concrete members, periodically immersed in sea water or subject to sea spray, the cover of concrete will be 50 mm more than that specified (a to e) above. i) For concrete of grade M25 and above, the additional thickness of cover specified in (f),(g) and (h) above a my be reduced to half. In all such cases the cover should not exceed 75mm. j) Protection to reinforcement in case of concrete exposed to harmful surroundings may also be given by providing a dense impermeable concrete with approved protective coating asmspecified on the drawings. In such case, the extra cover, mentioned in (h) and (i) above, may be reduced by the Engineer-in-charge, to those shown on the drawing. k) The correct cover will be maintained by cement mortar briquettes or other approved means. Reinforcement for footings, grade beams ad slabs on sub grade will be supported on precise concrete blocks as approved by the Engineer-in-charge. The use of pebbles or stones will be permitted. l) The minimum clear distance between reinforcing bars will be as shown in drawings. STRUCTURAL STEEL The work consists of furnishing and erecting of structural steel complete in strict accordance with this specifications and the applicable drawings. Materials : All structural steel will be of standard sections as marked on the drawings and will be free of scale, blisters, laminations, cracked edges ad defects of any sort. All structural steel and electrodes will comply in all respects with relevant I.S.S. for structural steel. Workmanship : All workmanship will be of first class quality in every respect to get greatest accuracy to ensure that all parts will fit together properly on erection. All ends will be cut true to planes. They must fit the abutting surfaces closely. All stiffeners will fit tightly at both ends. All holes in plates and section between 12mm and 20 mm thick will be punched to such diameter that 3mm of metal is left all around the hole to be cleaned out to correct size by reamer. Erection and Marking : During erection, the work will be securely braced and fastened temporarily to provide safety for all erection stresses etc. Permanent welding is used for permanent alignment only. All work will be taken down, painted or dispatched only if it has been inspected and passed. The contractor will supply free of charge all labour ad tools required for testing of work. Delivery at Site : The contractor will deliver the component parts of the steel work in an undamaged state at the site of the works and the Engineer-in-charge will be entitled to refuse acceptance of any portion which has been bent or otherwise damaged before actual delivery on work. ShopDrawing : The shop drawings of structural steel based on contract drawings hall be submitted to the Engineer-in-charge. The necessary information for fabrication, erection, painting of structure etc. must be furnished immediately after acceptance of the leader. Painting : Painting should be carried out on dry surfaces free from dust, scale etc. The paint will be approved by the Engineer-in-charge. Once coat of shop paint (red lead) will be applied on steel, except where it is to be encased in concrete or where surfaces are to be field welded. Welding : Type of Welding : Arc welding or Oxyacetylene welding may be used. Field welding may also be used. Field welding will use D.C. DAMP PROOF COURSE It consists supplying and laying plain cement concrete and cement plaster 1:3 as damp proof course with waterproofing admixture with this specification and applicable drawings. Workmanship : Surface to receive damp proof course will be cleaned and carefully wiped to remove all dust and laitance. Damp proof course is a cement concrete with cement plaster in the ratio CM 1:3. Approved water proofing compound @ 2% by weight of cement or as directed by the manufacturer will be mixed in cement mortar for this concrete or plaster. The damp proof course will be laid to the full width of the walls and the edges will be straight, even and truly vertical. Wooden forms will be used to obtain good edges. No masonry work will be commenced on freshly laid damp proof course unless it is cured for 48hours of its laying by curing of damp proof course will be continued along with the masonry work. Specification for cement, sand, aggregate and water will be as described herein before for concrete works / cement plaster. Mode of measurement : The work will be measured in sqm. area actually laid limited to sites as shown indrawing. The rate will include cost of all the materials, labour etc. and scaffolding . BRICK WORK Scope of work: The work covered under this specification pertains to procurement of best quality locally available bricks and workmanship of building walls of various thickness. In strict compliance with the specifications and applicable drawings. Materials : Brick will be best quality locally available bricks and will be got approved by the Engineer-in-charge before incorporation in the work. The nominal size of bricks (F.P.S) will be 22.9 X 11.4 X7cm (9″ X 4 1/2 X 2 3/4″ ). Permissible tolerance on dimensions will be + 3mm. in length and + 1.5 mm in width / thickness. Bricks will generally conform to IS 1077-1970. In any case minimum crushing strength will not be less than 35 kg/sq.cm and water absorption will not be more than 25% by weight. Bricks with appreciable quantity of sulphates and Chlorides will be rejected. Bricks will be thoroughly soaked in water before using till the bubles ceases. No half or quarter brick will be used except as closer. The closers will be cut to required size and used near the end of the walls. Workmanship : Four courses of brick work with four joints should not exceed by more than 40mm the same bricks piled one over the other without mortar. Brick work will not be raised more than 10 courses a day unless otherwise approved by the Engineer-in-charge. The brick work will be kept wet for at least 7 days. Brick work will be uniformly raised around and no part will be raised more than 1.0 metre above another at any time. All joints will be thoroughly flushed with mortar of mix as specified in the schedule of quantities, at every courses. Care will be taken to see that the bricks are bedded effectively and all joints completely filled to the full depth. The joints of brick work to be plastered will be raked out to a depth not less than 10mm as the work proceeds. The surface of brick work will be cleaned down and wiped properly before the mortar sets. The adhesion between the brick masonry surface and the concrete surface of columns, beams, chajjas, lintels etc. should be proper by ensuring that the concrete surface coming in contact with brick masonry is backed / chipped / keyed, cleaned and cement slurry is applied so that a proper bond is achieved between the two dissimilar materials. It is responsibility of the contractors to ensure that there will not be any cracks / fissure anywhere in the brick masonry. In case the cracks appear subsequently in those areas, they should be made good by cement grouting or epoxy putty grouting/ poly sulphide compound grouting or as per standard modern specifications/methods with the prior approval of the Engineer-in-charge, at the cost of the contractor. All the courses will be laid truly horizontal and all vertical joints will be truly vertical. Specified mortar of good and approved quality will be used. Lime will not be used where reinforcement is provided in brick work. The mortar should completely cover the bed and sides of the bricks. Proper care should be taken to obtain uniform mortar joint thought out the construction. The walls should be raised uniformly in proper, approved bond. In construction of the wall, first of all two end corners are carefully laid to line and level ad then it between portion is built, with a cord stretching along the headers or stretchers held in position at the ends. This helps in keeping the alignment of the courses and marinating them in level. Similarly all other courses are building RATE ANALYSIS Cost of materials at source and at site of construction. The costs of materials are taken as delivered at site inclusive of the transport local taxes and other charges. Purpose of Analysis of rates: 1. To work out the actual cost of per unit of the items. 2. To work out the economical use of materials and processes in completing the particulars item. 3. To work out the cost of extra items which are not provided in the contract bond, but are to be done as per the directions of the department. 4. To revise the schedule of rates due to increase in the cost of material and labour or due to change in technique. REQUIREMENT OF LABOUR AND MATERIALS The labour can be classified in to 1) Skilled 1st class 2) Skilled IInd Class 3) unskilled The labour charges can be obtained from the standard schedule of rates. 30% of the skilled labour provided in the data may be taken as Ist class, remaining 70% as II class. The rates of materials for Government works are fixed by the superintendent Engineer for his circle every year and approved by the Board of Chief Engineers. These rates are incorporated in the standard schedule of rates. Lead statement: The distance between the source of availability of material and construction site is known as “Lead ” and is expected in Km. The cost of conveyance of material depends on lead. This statement will give the total cost of materials per unit item. It includes first cost, Conveyance loading, unloading stacking, charges etc. The rate shown in the lead statement are for metalled road and include loading and staking charges. The environment lead on the metalled roads are arrived by multiplying by a factor a) For metal tracks – lead x 1.0 b) For cartze tracks – Lead x 1.1 c) For Sandy tracks – lead x 1.4 Note: For 1m3 wet concrete = 1.52m3 dry concrete approximately SP.Wt of concrete= 1440 kg/m3 (or) 1.44 t/m3 1 bag of cement = 50 Kg Tender Tender is an offer given in writing to execute specified articles or materials at a certain rate, within a fixed time, under certain conditions of agreement between the contractor and the party, which may be a government department or an individual. Contracts Contract is an agreement between two or more parties creating obligations that are enforceable or recognizable at law. It establishes an obligation of each party to fulfill what it is agreed to perform. Obligations of the employer 1. Appointing of the engineer to administer the contract 2. Provision of the site 3. Provision of information, permits, and approvals 4. Providing funds and making payments in accordance with the contract 5. Participation in consultations with the engineer to agree matters on claims or conflicts between parties. Obligations of the Contractor 1. Execution and completion of the works and remedying any defect therein. 2. Provision of: a. Labor, materials, plant, and equipment needed b. Preparation of progress report c. Works program for execution, and updating it whenever required d. Setting out of the works e. Measurement and/or assisting the engineer to do so f. Records of his personnel and equipment g. Sample of materials specified h. Testing and re-testing i. Temporary works j. Facilities for other contractors working on the site k. Keeping the site clean, and remove rubbish 3. The contractor is required to: a. Sign the contract when he is called to do so b. Obtain and submit securities, guarantees, and insurance policies c. Ensure that his representatives will be available on site at all times d. Prepare and submit the contractor’s docment, including “as built drawings” and manuals of operation and maintenance e. Attend to the engineer’s instructions f. Provide access to the employer’s personnel to enter the site g. Prepare and submit payment statement and docmentation h. To uncover works for inspection when required i. Rectify (Correct) defective works j. Secure or compensate the employer against any claims k. Submit notices to the engineer whenever he encounters circmstances that may cause future claims l. Getting approval before assigning sub-contractors or partners of the works m. Respond for consultation with the engineer 4. Comply with the applicable laws, labor law and other local regulations. Role of the Engineer Usually the employer will enter into a consultancy agreement with the engineer to design and supervise the works. The engineer will have no authority to amend the contract. Engineer role can be: 1. As the employer’s agent: a. Administration of the contract – dealing with the procedures, provision of information and interpretations, issuance of variations, approval of samples, etc. b. Cost accountancy and payments 2. As a supervisor: The engineer must ensure that the work is being performed to fulfill the contract docments. 3. As a certifier: The engineer is required to certify or approve the payments that should be paid by the employer to the contractor. Those payments should be made periodically, mostly on monthly basis, and should depend on the quantity of works finished by the contractor. 4. As a determiner: The engineer must act as a mediator to help the parties towards agreement in issues such as claims for reimbursement of costs or extension of time 5. Issuance of instructions and variations: 6. Include: issuance of additional or modified drawings, actions in relation to defective works, issuance of clarifications, giving approval, and ordering variations. TYPES OF CONTRACT Measured or Unit rate Contract In this type of contract, the price is computed by multiplying quantities of work executed by the unit rate offered by the contractor in his tender. The rates are usually set out in the Bill of Quantities (BOQ). Such contracts often used where there are significant changes in the quantities or working conditions. So, when there are certain reasonable differences of the quantities accepted by all the parties, then the contract can be paid for by multiplying the actual measured quantities by the unit rates. Advantages: 1. Suitability: This type of contract is widely used in the execution of large projects financed by public bodies or governments. It also suits the works which can be split into separate items and the quantity of each item could be estimated with reasonable accuracy. 2. The employer pays for the actual work executed. 3. The contractor usually allows for a certain margin of variation, with a clear mechanism for valuation of such variations. 4. The engineer / employer has liberty to provide some drawings during the execution of the project, after award. Disadvantages: l. The employer cannot be absolutely sure of the total cost of the project until the whole work is completed. In case the quantities in the BOQ are inaccurate or roughly approximated, the value of the work may vary considerably. The contractor may try to offer an unbalanced tender on the basis of his anticipation of the uncertainty of quantities of certain items. 2. Both the engineer and the contractor have to do considerable computations and book-keeping during the progress of work. 3. Extra works or varied items of work are often a source of conflict. The contractor may press for higher rates than he would have tendered for in the beginning. 5 Lumpsum contract In a lumpsum contract, the contractor agrees to carry out the entire work as indicated in the drawings and described in the specifications, for a specified fixed lumpsum amount. Sometimes, the contract makes provisions to adjust the “lump sum” allowing for extra work and limited variations. Normally, a bill of quantities is not usually included, and if included it does not form part of the “Contract Docments”, but may be used just for guidance. Instead, a schedule of rates may be of value to evaluate the cost of extras or omissions. Advantages: l. From the employer’s stand point, and if no extras are contemplated, the tender sum tells him the exact cost of the project. Sometimes the employer will be working within a tight margin of budget. 2. From the contractor’s stand point, because the design will often be prepared by him, the contractor can gain through proper planning and efficient management to increase his margin of profit and/or to control timing. 4. Both parties need less number of staff for book-keeping, accounting and measurement. Disadvantages: l. In lumpsum contracts, there should be a complete set of plans and specifications, or what is called “Employer’s Requirements” which should be sufficiently detailed. 2. Variations in lumpsum contract may trigger conflicts about whether or not a particular item of work falls within the agreed scope of work, and whether there has been a variation to such scope. 3. This type of contract will not be suitable for works with scope and nature that cannot be predicted accurately in advance. The outcome will be unfair for the contractor to assume all risks and uncertainties, or for the employer to pay a higher cost. Cost-plus contract This type of contract differs from both the measured and the lumpsum contract in that the employer agrees to pay the contractor for the actual cost of the work plus an agreed percentage of this actual cost to cover overhead and profit. The contractor agrees to execute the works based on the drawings and specifications and any other information that will be provided to him from time to time during progress of the works. The percentage to be paid should not be applied on the costs of salaries of the contractor’s staff, whether on-site or off-site. Advantages: 1. Early completion of the work – The work can be started even before the design and estimates are prepared. Decisions can be taken speedily, and flexibility allows adoption of alternates for construction to suit the Employer’s Requirements. 2. The quality of the work can be assured. The contractor is induced to perform the work in the best interest of the employer. 5. No conflicts will be anticipated as to extras or omissions. Disadvantages: 1. The final cost to the employer cannot be foretold. 2. Both parties have to do a lot of accounting and book-keeping regarding labour; purchase of materials and plant and use of equipment. 3. The contractor has no incentive to economize or finish the work speedily. Suitability: In spite of some drawbacks in certain cases, this form of contract can be used suitably for: a- Emergency works that require speedy construction and where no time is available to prepare drawings for it. b- Construction of special or expensive projects, such as palaces, where the cost of the work is of no consequence but the materials and workmanship to be purchased are just to suit the choice and taste of the employer. Remark: An alternate to the cost-plus contract is the cost-plus fixed fee contract, where the contractor will be paid for the actual cost of construction plus a fixed amount of fees for his overhead and profit. The fee does not fluctuate with the actual cost of the project. This factor may overcome the possible drawback of the cost-plus contract. Construction Management Contract (C.M.) In this type of contract, the employer engages a specialized construction manager (C.M.) to provide administrative service for him and manage the work on his behalf. The (C.M.) has full control on (Cost and Time), on the budget and programming, and is usually paid on a staff-reimbursement basis. The (C.M.) assists in choosing the design consultant and the various contractors for a project divided into packages (structural, finishes, electro-mechanical, etc.). The technical role is kept with the design-professional, but as to control, coordination, certification and dispute resolution, the (C.M.) normally possesses the major role. VALUATION It is the technique of estimating and determining the fair price or value of a property such as a building, a factory or other engineering structures of various types, land etc. Six important Purposes of Valuation:  Buying or Selling Property When it is required to buy or sell a property, its valuation is required  Taxation To assess the tax of a property, its valuation is required. Taxes may be municipal tax, wealth tax, Property tax etc, and all the taxes are fixed on the valuation of the property  Rent Function In order to determine the rent of a property, valuation is required. Rent is usually fixed on the certain percentage of the amount of valuation which is 6% to 10% of valuation.  Security of loans or Mortgage When loans are taken against the security of the property, its valuation is required.  Compulsory acquisition Whenever a property is acquired by law; compensation is paid to the owner. To determine the amount of compensation, valuation of the property is required. Valuation of a property is also required for Insurance, Betterment charges, speculations etc. Valuation of Building: Valuation of a building depends on the type of the building, its structure and durability, on the situation, size, shape, frontage, width of roadways, the quality of materials used in the construction and present day prices of materials. Valuation also depends on the height of the building, height of the plinth, thickness of the wall, nature of the floor, roof, doors, windows etc. The valuation of a building is determined on working out its cost of construction at present day rate and allowing a suitable depreciation. Six Methods of Valuation 1. Rental Method of Valuation 2. Direct Comparisons of the capital value 3. Valuation based on the profit 4. Valuation based on the cost 5. Development method of Valuation 6. Depreciation method of Valuation Market Value The market value of a property is the amount which can be obtained at any particular time from the open market if the property is put for sale. The market value also changes from time to time for various miscellaneous reasons such as changes in industry, changes in fashions, means of transport, cost of materials and labour etc. Book Value Book value is the amount shown in the account book after allowing necessary depreciation. The book value of a property at a particular year is the original cost minus the amount of depreciation allowed per year and will be gradually reduced year to year and at the end of the utility period of the property, the book value will be only scrap value. Capital cost Capital cost is the total cost of construction including land, or the original total amount required to possess a property. It is the original cost and does not change while the value of the property is the present cost which may be calculated by methods of Valuation. Capitalized Value of a Property The capitalized value of a property is the amount of money whose annual interest at the highest prevailing rate of interest will be equal to the net income from the property. To determine the capitalized value of a property, it is required to know the net income from the property and the highest prevailing rate of interest. Therefore, Capitalized Value = Net income x year’s purchase Year’s Purchase Year’s purchase is defined as the capital sum required to be invested in order to receive a net receive a net annual income as an annuity of rupee one at a fixed rate of interest. The capital sum should be 1×100/rate of interest. Thus to gain an annual income of Rs x at a fixed rate of interest, the capital sum should be x(100/rate of interest). But (100/rate of interest) is termed as Year’s Purchase. The multiplier of the net annual income to determine the capital value is known as the Year’s Purchase (YP) and it is useful to obtain the capitalized value of the property. Sinking Fund Method In this method, the depreciation of a property is assumed to be equal to the annual sinking fund plus the interest on the fund for that year, which is supposed to be invested on interest bearing investment. Rental Method of Valuation In this method, the net income by way of rent is found out by deducting all outgoing from the gross rent. A suitable rate of interest as prevailing in the market is assumed and Year’s purchase is calculated. This net income multiplied by Year’s Purchase gives the capitalized value or valuation of the property. This method is applicable only when the rent is known or probable rent is determined by enquiries. Direct comparison with the Capital Value This method may be adopted when the rental value is not available from the property concerned, but there are evidences of sale price of properties as a whole. In such cases, the capitalized value of the property is fixed by direct comparison with capitalized value of similar property in the locality. Valuation based on profit This method of Valuation is suitable for buildings like hotels, cinemas, theatres etc for which the capitalized value depends on the profit. In such cases, the net income is worked out after deducting gross income; all possible working expense, outgoings, interest on the capital invested etc. The net profit is multiplied by Year’s Purchase to get the capitalized value. In such cases, the valuation may work out to be high in comparison with the cost of construction. Valuation based on cost In this method, the actual cost incurred in constructing the building or in possessing the property is taken as basis to determine the value of property. In such cases, necessary depreciation should be allowed and the points of obsolescence should also be considered. Development Method of Valuation This method of Valuation is used for the properties which are in the underdeveloped stage or partly developed and partly underdeveloped stage. If a large place of land is required to be divided into plots after providing for roads, parks etc, this method of valuation is to be adopted. In such cases, the probable selling price of the divided plots, the area required for roads, parks etc and other expenditures for development should be known. If a building is required to be renovated by making additional changes, alterations or improvements, the development method of Valuation may be used. Depreciation Method of Valuation According to this method of Valuation, the building should be divided into four parts: 1. Walls 2. Roofs 3. Floors 4. Doors and Windows And the cost of each part should first be worked out on the present day rates by detailed measurements.The present value of land and water supply, electric and sanitary fittings etc should be added to the valuation of the building to arrive at total valuation of the property. Depreciation is the gradual exhaustion of the usefulness of a property. This may be defined as the decrease or loss in the value of a property due to structural deterioration, life wear and tear, decay and obsolescence. Methods for calculating depreciation 1. Straight line Method 2. Constant percentage method 3. Sinking Fund Method 4. Quantity Survey Method Straight Line Method In this method, it is assumed that the property losses its value by the same amount every year. A fixed amount of the original cost is deducted every year, so that at the end of the utility period, only the scrap value is left. Annual Depreciation, D = (original cost of the asset – Scrap Value)/life in years For example, a vehicle that depreciates over 5 years, is purchased at a cost of US$17,000, and will have a salvage value of US$2000, will depreciate at US$3,000 per year: ($17,000? $2,000)/ 5 years = $3,000 annual straight-line depreciation expense. In other words, it is the depreciable cost of the asset divided by the number of years of its useful life. Constant Percentage Method In this method, it is assumed that the property will lose its value by a constant percentage of its value at the beginning of every year. Annual Depreciation, D = 1-(scrap value/original value)1/life in year Quantity Survey Method In this method, the property is studied in detail and loss in value due to life, wear and tear, decay, and obsolescence etc, worked out. Each and every step is based is based on some logical grounds without any fixed percentage of the cost of the property. Only experimental valuer can work out the amount of depreciation and present value of a property by this method. FIXATION OF RENT Capitalized value of the property can be known by any of the methods discussed earlier and suitable value of year’s purchase is adopted according to the admissible rate of interest (8% or any other fair rate). Then, Net income = capitalized value / year’s purchase All possible outgoings are added to this net income which will give gross income from the property. Gross income or gross rent = Net rent + outgoings The standard rent = (Gross Income / 12) per month. CALCULATION OF STANDARD RENT OF A GOVT. PROPERTY (In Punjab / Haryana), standard rent is calculated on the capital cost of the residence and will be either: 1. (a) A percentage equal to the rate of interest on the capital ( which includes the cost on sanitary,water supply and electrical installation, fencing, boundary walls and service roads etc. as fixed from time to time) value of a building. In addition, municipal and other taxes and the expenditure for the maintenance of building are also realised, or (b) 6%per annum of the capital value of a building constructed/ occupied after 1992 whichever is less. 2. Municipal taxes etc. levied on the occupant will be payable to the occupant direct to the authorities concerned in addition to the above rent calculations. 3. If value of land to be considered a little less percentage says 1 to 2 % on value of land be taken for calculation of standard rent. References:  http://www.conteches.com/portals/0/Images/PDH%20Credits/Inspection,%20Evaluation% 20and%20Load%20Rating%20of%20Installed%20Culverts/photo1.jpg,  https://qph.ec.quoracdn.net/main-qimg-1587ff336e1995ee882b8be58040e158, Accessed on  http://www.lefiltredumonde.com/upload/2017/12/13/pin-reinforced-concrete-box-culvert-design- on-pinterest-concrete-box-culvert-design-l-dfc6df8014e0fa7f.JPG  https://www.civilgeo.com/wp-content/uploads/sites/3/2015/04/xculverts-for-stream-crossing.jpg. pagespeed.ic.Na4RlHcrXK.jpg,  http://2.bp.blogspot.com/-O7LuiAFYApg/UiO_YiUuWPI/AAAAAAAAJXM/BPadBB9gdMk/s1600/ IMG_0026.JPG  http://www.nzdl.org/gsdl/collect/cdl/archives/HASH0159/039aacbc.dir/p040.jpg  https://i.ytimg.com/vi/PA4ZtEc81J0/maxresdefault.jpg, Accessed on 12 January 2016.  Roads and Highways Department, Bangladesh, Basic Information on the RHD Bridge Network, at http://www.rthd.gov.bd/bridge_maintenance.php  http://www.natureclean.com/picts/Seppic1.jpg, Accessed on 1 December 2016.  https://oldcastleprecast-yut3re1sojoa.netdna-ssl.com/wp-content/uploads/product-image media/5193_BG_LEX_BoxCulvert-Varies_01.jpg, Accessed on 1 December 2016.  www.civiljungle.com  www.researchgate.net  www.civilengineer.webinfolist  “Quantity Surveying and Estimation” by Dr. Hesham Ahmad  www.easyengineering.net  www.civildatas.com  www.homeforconstruction.com Sources:  Dutta, B.N., “Estimating and Costing in Civil Engineering”, UBS Publishers & Distributors Pvt. Ltd., 2003  Kohli, D.D and Kohli, R.C., “A Text Book of Estimating and Costing (Civil)”, S.Chand & Company Ltd., 2004  www.academia.edu  www.slideshare.net  www.lecturenotes.in  www.homeforconstruction.com  www.billingengineer.com  www.wikipedia.com

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