DIGITAL TAKEOFFS: FACTORS THAT WILL IMPACT QUANTITIES
TAKEOFFS – arguably THE most crucial step in the bidding process. Without a thorough takeoff (cut and fill) process to accurately quantify the materials (e.g., concrete, soil, asphalt, pipes, etc.) needed for your project, your estimates can be way off. Whether you're using a manual process or a digital process, errors in takeoffs result in inaccurate bids and additional expenses.
Factors That Will Impact Quantities
Our team has in-depth knowledge and expertise when it comes to creating digital takeoffs. Over the years, we have come across our fair share of situations that have impacted takeoff quantities. Have you experienced the same with any of these?
Topsoil depths
Existing buildings with basements
Subgrade depths
Undefined retaining walls
Bedrock
Proposed basements or foundations
Over excavation/unsuitable soils
Vertical vs. Horizontal measurement of a sloped area
Footing Overexcavations
Let's take a closer look at how some of those situations impact takeoff quantities:
Topsoil Depths
Topsoil depths vary widely from being shallow to being deep. Depending on how much or how little topsoil there is on the job site, the takeoff quantities could be impacted. Topsoil does not have the required integrity needed to support structures; therefore, it can only be reused for the project's landscaping portion. Figuring out the right amount of topsoil you'll need will allow you to determine then how much you may need to haul off the site and how much suitable soil you'll need to bring in.
Retaining Walls
Another situation that we often see is undefined retaining walls. When retaining walls are not adequately defined in the plans, they will impact your cut and fills, which could result in a false fill amount or an excessive cut amount in your takeoff. So, it is critically important to define retaining walls correctly.
Undefined Basement or Foundation
The issue with existing basements and foundations is when you're creating your existing conditions, and there is a building with an undefined basement or foundation. This could have severe impacts on your takeoff quantities because, depending on the size of the area and depth of the basement or foundation, you may need to bring in a lot of material to fill it in. It is essential to have the basement or foundation levels factored into your quantities to not end up with false amounts.
Unsuitable Materials
Another scenario is when excavating has begun, and unsuitable materials have been discovered. This means you will have to excavate more than what you had planned for, and therefore your takeoff quantities will be off. You'll have to adjust your quantities for the amount of suitable materials that will need to be brought in to replace the unsuitable materials found during the digging process.
Sloped Areas
Finally, how do sloped areas impact your quantities? Well, given that plans are in 2D, but we live in a 3D world, it happens a lot that your calculation may be based on your planview area. Looking at a steep slope from this viewpoint does not allow you to factor in the elevation component. When you take into account the slope of the area, it will more accurately reflect the square footage of the slope, which is a better assessment of the existing land and will give you a more accurate takeoff quantity.
There is no doubt that a thorough takeoff improves estimates. When you factor in overhead costs, market price changes on materials, and other expenses together with your takeoff quantities, you will end up with reliable estimates every time. By contacting ECI, you'll be one step closer to achieving your takeoff goals. Our virtual construction engineering team will work together with you to produce the highest quality digital takeoffs so you can increase your chances of winning those bids!
Detailed Takeoffs Result in Better Bids