Quantity take-offs (QTO) are a detailed measurement of materials and labor needed to complete a construction project. They are developed by an estimator during the pre-construction phase.
Tools Required to Perform a Construction Takeoff
- Manual Construction Takeoff with Printed Plans
- Construction Project Drawings Printed to Scale
- Highlighters and/or Color Pencils
- Hand Tallying Tool (click counter)
- Digital Scale Master or Engineering Rulers
- Quantity Takeoff Form
- Construction Takeoff with Digital Plans
- Drawings in PDF Format or Image Format
- Computer, Laptop, or Tablet
- Excel or Integrated Estimating Module
What stage in the project should a Quantity Takeoff take place?
Quantity takeoffs are generally performed early on during the bidding process.
During the estimation process, an estimator may have to make frequent adjustments to the quantity takeoff, typically due to:
- Design changes
- Additional engineering requirements
- Changes in what the client wants.
Thus, the quantity takeoff is often a living document that undergoes many changes until a design is decided and a bid is secured.
While this may not be the case for smaller projects, large or complex projects will almost certainly require many revisions to the quantity takeoff.
MANUAL MATERIAL TAKEOFFS
This is the oldest and simplest material takeoff form. Manual material takeoffs involve the estimator taking physical plans or blueprints and carefully detailing every material type and quantity specified on the construction drawings. This is a time-consuming data management process and prone to human error. It’s the estimator’s knowledge of materials, experience in estimating and skill in taking off material quantities that ensures accuracy. With manual methods, there’s no substitute for attention to detail.
DIGITAL MATERIAL TAKEOFFS
Performing material takeoffs through computer analysis and database application is relatively new in the construction industry. The first effective CAD-based programs date back to the late ’80s and ’90s, and their sophistication quickly evolved to include computerized building models integrated with digital takeoffs. Digital takeoffs are superior to manual methods for large and complex projects because of their speed and thoroughness. The qualifier is the takeoff technician being properly trained and proficient with the software application as well as highly attentive to applying the takeoff information into cost-based results.
Quantity takeoffs can be complex and involved processes. However, they have a single purpose, and that’s accurate data management. Whether you employ manual takeoff personnel or equip them with the latest digital takeoff program, the outcome must be an accurate list of all materials required to complete the project. It also has to conclude with a meaningful price structure.
Two Main Steps of the Construction Quantity Takeoff:
The first step of the construction quantity takeoff process is creating a list of all the materials. The materials needed to complete the construction project. The raw materials included in the construction quantity takeoff are such as concrete, fabric, glass, cement composites, sand, clay, pipes, and lumber, etc.
In addition to the raw materials, the construction quantity takeoff will include as well the prefabrication that is important for the construction project.
The estimator needs to define all the materials’ specifications. This means that the estimator should for example specify the type of pipes. He also should specify the quality, the length, and the width of the pipes, and the total weight of the pipes. So they could ensure that the pipes would meet the design specifications. And also the cost is suitable for the whole budget.
If the Estimator decided to do the construction quality takeoff manually, he should be able to do many complex calculations. Some materials should be calculated in the area or square feet and other materials in volume, or in weight.
The point that each estimate should take care of is taking into consideration ordering an extra amount of each material as well. He should take into account wastage during the process of the construction project.
After preparing the materials list with all the details needed to complete the construction project, the estimator will prepare the material price estimate.
In the case of large projects, the estimator will search for a bid from a material supplier. And reaching the total material cost will be very time-consuming.