What is the Estimation, Quantity Survey?
Before beginning work on the project, the quantity of all materials and their total cost are calculated.
As a result, Amount Surveying or estimation is the art or expertise of determining the material quantity and total cost.
Estimating is another name for it.
Quantity surveying is essential in the estimation and construction of any project.
It will assist in determining all associated applicable expenses and material quantities so that all of those aspects are decided, and funds are released for the project if acceptable.
If funds are limited, some changes can be made to keep the project within the defined budget.
These changes can be made to the project specifications, or the project can be completed in stages so that it can be completed within the available finances.
In any case, the project should not be underutilized.
Regardless of the nature of the project, such as construction, sewerage system, canal digging, or road construction, estimation is done in two methods.
Initially, a rough cost estimate is performed to aid in cost assessment.
Finally, if funds are released, the Detailed Estimate is performed.
A quantity surveyor is someone who makes estimations.
This individual is also known as an Evaluator or Estimator.
Estimation cannot be performed without first knowing the relevant project's drawing.
- Understanding and reading the drawings requires skill.=
- Intended to be knowledgeable in Quantity Surveying
1. Drawings.
The estimate is prepared according to the drawings.
Drawings depict the heights, lengths, and thicknesses of different parts of the project.
The size of every component of the project is shown in the drawing and an estimate is prepared accordingly.
Plan, Elevation, and Sectional Elevation are common forms of drawings prepared in the process of building estimation.
Drawings depict the heights, lengths, and thicknesses of different parts of the project.
The size of every component of the project is shown in the drawing and an estimate is prepared accordingly.
Plan, Elevation, and Sectional Elevation are common forms of drawings prepared in the process of building estimation.
2. Specifications.
Specifications and drawings are assigned to show the project's excellence.
A sketch, for example, can reflect the dimensions of the door but not some fundamental characteristics such as door type and timber kind, etc.
There are various types with varying pricing.
Specifications show all of these elements.
There are two kinds of specifications.
a. General Requirements.
b. Specifications in detail.
a. General Requirements:
General Specifications are sometimes known as Brief Specifications.
They're utilized to show the aspect, standard, and type of construction work.
They would depict the broad categories of the project's construction activity.
These specifications are utilized to set the construction work standards that will aid in the preparation of the Detailed Estimate.
b. Detailed Specifications:
In the thorough description, detailed specifications reflect the features, quantity, ratio, and formation process of the material used in building work.
Detailed Specifications are used to detail each component of the construction work independently.
As a result, all aspects determining building standards and quality are disclosed.
As a result, it will help with the detailed estimate.
Detailed specifications for products utilized in routine projects are printed and used for contracts.
Standard Specifications are the name given to these specifications.
3. Rates.
For proper estimation, accurate material and construction work rates are required.
These rates must be grounded in reality.
The project's cost will be estimated by multiplying rates by the material's or building effort's magnitude.
Material or constructional work rates can be determined using the Schedule of Rates of various public and private departments, or completed construction work can be reviewed to obtain all required rates.
Rates include material charges, transportation charges, and labor charges, among other things.
Types of Estimate in Civil Engineering.
The following are the two Primary Types of estimates.
1. Original Estimate.
2. Repair Estimate.
So, Let’s describe the types of estimates in detail.
1. Original Estimate.
The original estimate is one generated for a newly proposed project.
For example, this project could be a building, canal, or road construction project.
In other words, if these projects are started from the ground up, the estimate proposed will be the Original Estimate.
It is accomplished in two methods, as follows.
a. An approximation of the cost.
b. Exact Estimate.
a. Rough Cost Estimate.
This type of estimate is done for any project before it begins to determine its viability and the cost that will be incurred.
Initially, a rough cost estimate is performed on the project, which is known as the Rough Cost Estimate.
This assessment compares predicted financial income and a rough cost estimate if the project is planned for financial gain.
If the project is not offered for financial gain, its necessity and vitality are weighed in this form of an appraisal.
A rough cost estimate is calculated by comparing the costs incurred during previous project experiments to the expenses incurred during the current project.
It comprises the cost of the project's site as well as the cost of the structure itself. Water supply and price of sanitary, provision of gas and electricity.
Rough Cost Estimate additionally includes 5 to 10% of additional expenses that must be made on an urgent basis throughout a project and are not visible before project start-up.
These are referred to as contingencies.
For Administrative Approval, a rough cost estimate is performed.
It is carried out in various ways for various types of projects.
Some examples are as follows.
a. For Buildings.
Different methods are used for conducting Rough Cost Estimates for buildings.
The most well-known methods have been explained below.
i. Per Unit Number.
In this method of Rough Cost Estimate for building, the cost estimate is done per unit number according to the aspect of the project.
For example, this method will consider per student cost in case of school construction, per bed in case of a hospital, and per seat in case of a cinema or theatre.
Per unit, the rate is established respecting certain factors such as material, labor, etc.
ii. Plinth Area Basis.
A rough Cost Estimate of the building is generally conducted by the Plinth Area Basis method.
In this method, the entire proposed construction area of the building is determined.
This area is known as Plinth Area.
The plinth area will include the area for all types of rooms, verandas, walls, etc.
This area is determined by finding all the measurements over the Plinth Area of the building.
Then, Plinth Area is multiplied by the appropriate rates.
This rate is established by observing the material used in the building and its specifications.
The rates can be found by the already constructed buildings in the area and their whereabouts.
Hence, acquired expenditure will be the proposed expenditure for building construction.
It will include the provision of gas and electricity, sewerage, and all related facilities.
These expenses are usually retained in a percentage manner as follows.
- Water Supply and Sanitary = 8%.
- Electrification = 8%.
- Gas Supply = 4%
All these expenses that are paid over facilities are accumulated with the cost paid for building construction.
Subsequently, Contingencies are added up to the final submission.
Contingencies may vary from 5 to 10 percent of the overall cost of the building.
Finally, Rough Cost Estimate, for the building will be ready.
10% profit for the contractor must be added to the overall cost if the project has to be done by contract.
In the case of a multi-storied building, the separate cost is determined for each story.
If the drawing of the building is not available or not yet prepared, then the area of the required rooms is determined, and 30 to 40 percent area is added up for passages and verandas.
Ultimately, Plinth Area is determined. Rough Cost Estimates can be found in this area as well.
iii. Cube Rate Estimate.
This method of Rough Cost Estimate determines the total volume of the proposed building.
Then it is multiplied by the Rate Per Unit Volume, and the overall cost of the building is found.
Outer measurement of the building is acquired for finding the volume of the building.
These measurements include the length, height, and width of the building.
All these measurements are multiplied together to get the volume of the building.
The height of the building starts from the plinth to the upper surface of the floor of the building.
Foundation and Parapet are not included in it.
The rate Per Unit Volume is selected according to the type of the building and related specifications.
These rates can also be established by already constructed buildings and their whereabouts.
The cube Rate Estimate method is the best for establishing a Rough Cost Estimate as it also involves the height of the building.
iv. Per Unit Length of Wall.
The lengths of different walls are calculated separately in this Rough Cost Estimate approach.
The cost of each wall's unit length is then determined.
This cost is calculated separately for the foundation and the Super Structure.
The cost of the Damp Proof Course, as well as the cost of excavating and filling, will be included in the foundation cost.
The cost of a superstructure includes masonry, woodworking, roofing, and finishing, among other things.
b. For Roads and Highways.
A rough cost estimate for roads and highways is developed per Kilometre.
The cost per Kilometre is determined by the type of road or highway built.
This cost is determined by the width of the road, the material used in its construction, and the road's design.
The total cost of the road is calculated by multiplying the whole length of the road by the Rate Per Unit Length of the road.
c. For Irrigation Channels.
There are two methods for obtaining a rough cost estimate for an irrigation channel.
In the first instance, per kilometer expense over the irrigation Channel is determined.
The entire cost is then calculated by multiplying the canal's total length.
In the second step, the overall cost of the irrigation channel is calculated based on the harvesting area that would be watered by the proposed irrigation channel.
This method determines the cost or expenditure per acre.
The entire cost of the irrigation channel is then calculated by multiplying the total cost by the whole area.
d. For Bridges and Culverts.
The cost of small culverts is calculated per culvert.
The cost of major culverts and bridges is calculated per meter span of the culvert or bridge.
e. For Water Supply or Sanitary Line.
Rough Cost Estimate of Water Supply and Sanitary pipelines is ensured using two ways.
The first technique establishes a cost per head for the entire region, which is multiplied by the entire region's population to obtain the overall cost of the Water Supply and Sanitary Pipeline.
The second technique establishes a cost per acre for the entire region, which is multiplied by the region's total area to obtain the overall cost for the Water Supply and Sanitary Pipeline.
f. For Overhead Water Tank.
The cost of building an overhead water tank is dictated by its storage capacity.
Cost Per Litter is established for over-head water tanks with respect to height and construction approach in order to create a Rough Cost Estimate.
Following that, the cost of the tank is calculated by multiplying Litter by the capacity measurement.
g. For Railway Track.
A rough Cost Estimate is established per Kilometre for constructing railway tracks.
Cost Per Kilometre is established with respect to railways line gauge, rail, and type of sleeper.
Then this cost is multiplied by the length of the railway track to get the overall Rough Cost Estimate.
b. Detailed Estimate.
Each project item is determined in this estimation method, and the cost is calculated by multiplying it by its Unit of Rate.
Detailed estimate includes all types of costs.
As a result, it is regarded as a more accurate estimation method.
A detailed estimate is created in order to obtain Technical Sanction approval for the connected project.
This type of estimate includes the following information.
- Project Report.
- Specifications.
- Detailed Drawing.
- Design Data.
- Rates.
This estimate also determines whether a tender is required to complete the project.
As shown below, a detailed estimate is provided for purposes other than the original building.
- Revised Estimate.
- Supplementary Estimate.
- Revised and Supplementary Estimate.
a. Revised Estimate.
A Revised Estimate is created when a deviation of more than 5% occurs in the Detailed Estimate.
Diversion happens as a result of price fluctuations.
If changes are made to the project design of the previously prepared Revised Estimate, a new Revised Estimate is prepared, and Technical Sanction is obtained.
This estimate is carried out in the same manner as the Original Estimate.
A Comparative Statement is also included with the Revised Estimate to clarify the pricing fluctuations in each item.
b. Supplementary Estimate.
If the project's construction work has begun and a change in design is felt,
..when spending owing to design changes cannot be covered within approved funds, an extra estimate known as a Supplementary Estimate is generated.
The Supplementary Estimate technique will be comparable to the Original Estimate procedure.
Along with the Supplementary Estimate, a report is created to justify the need for change or addition.
This estimate will include the previously authorized Estimate and the Supplementary Estimate.
c. Revised and Supplementary Estimate.
Modifications or additions to previously established project estimates are sometimes required, and these changes are triggered by price deviations of greater than 5%.
Cost adjustments are caused by design modifications in projector price fluctuation of the items.
If the estimate indicates that additional costs of more than 5% will be incurred before the start of the project or during its construction,
The divisional officer (XEN) then has the power to create a new project estimate and get a new Technical Sanction for the project.
This revised estimate will be referred to as the Revised and Supplementary Estimate.
If the cost of the updated estimate is less than the previous estimate, the estimate is known as a Reduced Estimate.
2. Repair Estimate.
Buildings and other structures require repair and maintenance to be maintained and cared for.
The estimate was created to determine the cost of the repair.
This is known as a Repair Estimate.
The repair estimate technique is comparable to the detailed estimate procedure.
The building repair estimate covers whitewashing, painting, and other maintenance.
Road repair will entail patching up holes in the road's surface, ensuring the rigidity of the road banks, and maintaining footpaths, among other things.
The many sorts of repair estimates are listed below.
- Annual Repair Estimate.
- Quadrennial Repair Estimate.
- Special Repair Estimate.
i. Annual Repair Estimate.
Every year, buildings and other structures are repaired to keep them in good condition and useable.
Annual Repair Estimate refers to the estimate prepared for such repairs.
This quote includes whitewashing and minor repairs. A budget of 1 to 1-1/2 percent of the total cost is set aside for this reason.
Every year, road edges and shoulders are fixed and maintained as part of the yearly maintenance program.
The Annual Repair Estimate technique will be comparable to the Detailed Estimation procedure.
ii. Quadrennial Repair Estimate.
Despite regular repair, a special repair called Quadrennial Repair is performed every four years.
It entails painting and restoring ruined plaster.
Regardless, it involves the repair of doors and windows.
The Quadrennial Repair Estimate technique will be comparable to the Detailed Estimation procedure.
iii. Special Estimation.
For unique repairs, tenure is not fixed.
However, damage to buildings and other structures caused by earthquakes, floods, and other accidents is repaired in a particular repair.
Despite this, buildings and other structures suffer severe damage and a deplorable state due to continuous and protracted usage, and they are explicitly restored to make them lovable and usable.
The particular repair will include removing the damaged floor or roof and replacing it with a new one.
Removing broken doors and windows and constructing a new one, removing ruined plaster and plastering a new one, and so forth.
Road special repairs will involve filing up patches that have appeared on the road's surface, guaranteeing the rigidity of the road banks, and footpath upkeep, among other things.