An estimator must know the types and quantities of different types of materials before bidding or starting a project. The knowledge assists in ascertaining an accurate estimation of the cost and requirements for the elements to provide an estimate of the value involved for labor in the installment or construction of the materials.
As per the construction drawing and specification management standards, the process is called takeoff or material take off (MTO). It is vital in the estimation process. For a small construction project, an experienced builder should estimate the materials needed for his or her head. A thorough process is required for the main construction projects. Nonetheless, it is essential to take up the task in a systematic manner to achieve the correct approximation possible. It also provides an exact estimate and runs the construction process smoothly by ascertaining that the workers or contractors can have all they want.
It must be noted that though a detailed takeoff can boost the estimate, there are other factors which can affect the process and therefore must be considered. It involves shifts in market prices, office overhead costs, and other expenses.
How to read a construction drawing? What should be counted?
Generally, the takeoff should assess all the materials required for completing the structure, building or project. A takeoff does not involve assets such as equipment and tools. While these are needed to accomplish the job but these must include all the physical materials going into the project. These may be raw materials such as sand or timber, concrete including prefabricated elements: light fixtures, plumbing pipes, electrical cable, and bricks. Along with counting the items, the material takeoff should specify the type of material needed. For instance, the kind of electrical wire or the grade of steel.
Various contractors have a varied range of requirements when compiling the takeoff. Materials used by a roofing specialist are different from the concrete contractor, but the principles of takeoff remain the same.
There are four types of measurements needed to measure the full scope of work, and this should be included in most of the construction estimates and bids. The focus four are count, length, area, and volume and are a must-have in knowing how to read a construction drawing.
An estimator is required to match like details with like details and thus find out the total quantity of the details involved in the scope of work to evaluate count. It could vary from the number of light fixtures for a given building to the number of studs required to complete the project. For instance, if an estimator is taking off a plumbing scope of work, then they need to count the number of plumbing fixtures.
A few items can be measured only on the basis of length such as cables and pipes. Though you would want to know other dimensions such as diameter, it is included with the type of material needed. The estimator requires to determine the length for certain conditions which can be best measured as a length calculation. When an estimator is working on a roofing project, he would want to establish the requirements such as length of walls to decide the labor and material quantities.
A few materials will need a measurement of the surface area. It includes elements including cladding, flooring or a rough estimate of the amount of paint required for a given structure.
Volume measurement may be required for some materials including the amount of asphalt to be used per yard or the concrete that is needed to lay the foundation.
Types of Takeoff
It is an essential aspect in discovering how to read a construction drawing.
There are two types of takeoffs:
A lot of construction designs professional make use of the traditional style of using paper blueprints and plans, and it is possible to execute a correct takeoff from these materials. Nevertheless, it is essential that the estimator should read the blueprints and plan accurately for the kind of work quantified (plumbing and electrical schematics, etc., general building plans). Along with the diagrammatic representations of the dimensions of the project, these comprise of various notes and symbols, and these specify the types of materials needed.
When working from these design plans, the user can make use of pencils, colored pens, or markers to differentiate the various items and types of the materials specified. Paper blueprints can be costly and consume a lot of time to produce, a lot of estimators have moved on to new technology to carry out the estimates.
However, a manual takeoff can be utilized to generate an accurate estimate, but it can be complicated and strenuous. It can also showcase errors when you get a count, measurement or the calculation wrong.
A lot of companies are creating digital blueprints today. You can get a variety of takeoff software which can be employed to streamline and automate a takeoff process. Though the specifications may vary from software to software, but most allow the user to analyze the blueprints and enter the measurements and quantities needed in a digital format. A few systems can be integrated within a bidding or quotation program. This allows combining the two processes.
Break Down Of the Process
The accurate details of the takeoff process can vary depending on many factors on the basis of construction drawing and specification management standards. This comprises of specialization as an MEP estimator, types of drawings used, software underuse and the nature and scale of the job. The specifications and drawings would be vaguely different; however, the general techniques remain the same.
Check out of the breakdown of the primary manual takeoff process for the electrical components of a project.
Counting the Symbols
The counting symbols let you to recognize the number of components needed to finish the job. The drawings and blueprints you work uses standardized symbols to present various items including switches, fixtures, and convenience receptacles. The user requires to get familiarized with the symbols and the components they represent. Other non-standard components can be identified by a key included on or with the drawings.
Measuring the Circuits
The circuits displayed in the drawings are required to be measured according to the construction drawing and specification management standards. First off, check the scale needed for each page you measure. The scale dimensions are usually found listed in the title block of the drawing, but it should be noted that the scale can vary on different pages, therefore, do check for scales listed on each page.
When working with the original blueprints, remember that these must have been copied to a minimized size. It is essential to confirm the scale or contact the designers and architect if there are doubts in mind.
Calculating the Takeoff
Make use of the measurements and the counts to generate a takeoff figure. With the trade market values, an accurate estimate of the cost of the materials involved can be provided. With the motion data required and right time, you can measure the scale of the job to approximate labor on the project with other associated costs.
The tips above should help you in understanding how to read a construction drawing and master the takeoff in construction drawing project. An accurate estimate is essential while working on a construction project. Remember the guidelines for inexpensive solutions while starting new development and follow the construction drawing and specification management standards.
- Posted On: January 14, 2019
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