Common Mistakes in Material Takeoffs and How to Avoid Them

Accurately estimating the needed materials for construction comes as a daunting task for an estimator or project manager. The extent of lasting damages to a project stemming from a materials takeoff error runs dangerously high, and includes, but is not limited to, added costs, wasted time, and delayed deadlines. This definitely sounds familiar to anyone who has experienced the exacerbating consequences associated with either a material shortage or the overflowing surplus of materials delivered to a construction site. My main question is, how would one steer clear from these misconceptions while guaranteeing maximum accuracy throughout the entire estimating process? 

This is precisely the direction I’ll be taking with this article; share lessons learned from personal experiences throughout my construction career. Along the way, we will discuss the myriad ways through which material takeoff estimations can go awry. But more critically, we will ensure that material takeoff estimation is approached in a manner that makes certain project remain within scope, are budget-friendly, and are completed on schedule.

What is a Material Takeoff and Why Does It Matter?

Before we discuss common errors, let us first analyze why a material takeoff (MTO) is crucial. In simple terms, a material takeoff refers to calculating the materials required for a construction project. It helps in cost estimation, planning procurement, and ensuring construction workflows seamlessly by allocating the right materials at the appropriate times.

As someone who has been involved with numerous projects ranging from small residential builds to large commercial ones, I have experienced how takeoff inaccuracies can be a project derailleur. These errors, whether an overestimation or underestimation, will affect budgets, timelines, and overall project success. Let us, therefore, discuss the most common errors associated with material takeoffs and how you could avoid them.

Common Mistakes in Material Takeoffs and How to Avoid Them

1. Incomplete or Missing Measurements

When working on-site, I find that one of the most challenging is pertained to omitted or missed measurements. I’m guilty of missing a detail or two when it comes to bulk take-off procedures in the construction project management process. At first glance, this does not appear to be a major challenge, but it can create some quite large problems later.

Solution:

• Double-Check All Measurements: Use accurate tools like laser distance meters and digital takeoff software to capture every necessary measurement. I always make sure to revisit the site if I’m unsure about certain measurements. A small mistake can easily snowball into a bigger issue.
• Cross-Reference with Blueprints: Always make sure you’re working with the most up-to-date blueprints. I’ve learned the hard way that relying on outdated plans can lead to material discrepancies that are expensive and time-consuming to fix.

2. Not Accounting for Material Waste

In the initial stages of my professional journey, I neglected to consider waste due to cuts, errors, or intrinsic flaws in the materials. This step was essential; otherwise, I found myself rushing to order additional materials which resulted in self-imposed deadlines. This, in turn, increased my costs. I came to understand that construction materials such as drywall, concrete, and lumber have accompanying waste factors that must be considered during measurements.

Solution:

• Include a Waste Factor: I now always account for 5-10% additional material for waste, depending on the material type. This has saved me from last-minute shortages and the headache of rushing to suppliers. For example, I add more when working with lumber or sheet materials, which tend to have higher waste rates.
• Consult with Suppliers: I also ask suppliers for waste factors when I’m unsure. Many suppliers will have a recommended waste percentage based on the material’s history in similar projects.

3. Using Outdated or Incorrect Plans

There was a project in my previous work where the most recent blueprint was not disseminated to the team. We followed an old version and by the time we noticed other changes like expanding the floor plan and adding new rooms, we had already started the ordering phase. This mistake delayed the project completion timelines and increased expenses.

Solution:

• Always Use the Latest Plans: Now, I make it a habit to double-check the plans with the design and engineering teams before starting any material takeoff. Staying in constant communication is key.
• Version Control: I recommend using digital project management tools where revisions are tracked, and everyone has access to the most current plans.

4. Relying Too Much on Manual Calculations

Before, I depended a lot on hand draw takeoffs and manual calculations. Even though it can be done with smaller projects, it is highly inefficient for larger projects. I remember some instances where I miscalculated material requirements which led to delays and inconveniences with the contractors and suppliers.

Solution:

• Invest in Software Tools: I’ve switched to using material takeoff software like ProEst and PlanSwift. These tools not only automate the calculations but also help in visualizing the quantities. The speed and accuracy they provide are invaluable, especially when dealing with large or complex projects. I also recommend software that integrates with project management systems to streamline the process.
• Train Your Team: If you’re working with a team, it’s important to ensure that everyone is trained on the software. This minimizes errors and improves consistency.

5. Overlooking Site-Specific Conditions

Once, I underestimated the materials needed for a project due to site conditions. A construction site may seem straightforward on paper, but factors like uneven ground, steep slopes, and hidden structural elements can change the material requirements.

Solution:

• Visit the Site Regularly: I’ve found that it’s essential to conduct multiple site visits throughout the planning phase. I also recommend bringing along key team members, such as the site manager or foreman, to identify potential challenges early on.
• Account for Variables: Adjust your takeoff to reflect the site’s unique features, such as soil conditions or areas with difficult access. This ensures you don’t face surprises during construction.

6. Misunderstanding Units of Measurement

I once had a major mishap when ordering materials for a project that used both imperial and metric units. The conversion errors led to discrepancies in quantities and, unfortunately, unnecessary delays and frustration.

Solution:

• Clarify Unit Conversions: This mistake taught me the importance of clarifying the units of measurement beforehand. I now ensure that all measurements are converted to the same system before the takeoff process begins.
• Standardize Units Across the Team: When working with a team, it’s essential to use the same system across all members. This prevents confusion and errors during the ordering process.

7. Poor Communication with Suppliers and Subcontractors

In my previous projects, the interplay (or lack thereof) between the estimator and suppliers more often than not ended in miscommunication which resulted in delays. This is most noticeable when it comes to the provided list of materials and their description. Inaccurate descriptions can lead to the provided materials being different than what is actually needed for the project, which in turn, impacts the entire project timeline.

Solution:

• Clear and Consistent Communication: I’ve found that regular check-ins with suppliers and subcontractors can help ensure everyone is on the same page. Always confirm material orders in writing and double-check the specifications.
• Use Project Management Tools: Using shared platforms where materials and orders are tracked helps ensure all parties are aligned throughout the process.

Best Practices to Ensure Accuracy in Material Takeoffs

Here are some best practices I’ve implemented that have greatly improved my material takeoff accuracy over the years:

• Use Technology: Leverage software to automate and simplify the takeoff process. It saves time, reduces human error, and ensures accuracy.
• Standardize Processes: Develop a standardized method for material takeoffs that your entire team follows. This minimizes mistakes and ensures consistency across projects.
• Review and Double-Check: Always have another set of eyes review your takeoff to spot errors you may have missed.
• Work with Experts: Bring in seasoned estimators and quantity surveyors for large or complex projects to ensure everything is accounted for.

Conclusion

Although material takeoffs appear to be a simple task, the issues noted here every so often result in expensive outcomes. From my experience, the most accurate measurements are taken with the most recent plans, up to date tools, and waste allowances, modern tools, and accurate plans. By applying the solutions outlined here, you will reduce inaccuracies, control expenses, and ensure an efficient project schedule. Achieving accuracy in material takeoffs translates to easier projects, better respect from clients, and reduced stress for all parties concerned.

FAQs

Q1: What are the best tools for material takeoffs?

Software like ProEst, Buildertrend, and PlanSwift can automate your material takeoff process, ensuring accuracy and efficiency.

Q2: How can I prevent material shortages?

Always account for waste and double-check all measurements before ordering materials. Using software tools can help automate this process for you.

Q3: How often should I update my material takeoff?

Update your takeoff whenever there are significant design changes or revisions to the plans. Regularly check for new updates to ensure accuracy.