Improve Earthwork Estimates with Drone Data

As an estimator, you have to take many things into consideration when placing a bid: materials, labor and equipment required, different quotes from different subcontractors and suppliers, and the quality of all of these goods and services.

Your estimates must be competitive while maximizing profitability—an extremely difficult balance to strike. Your decisions can make or break a tender if the price is wrong or the quality isn’t high enough.

There are some great tools available to you (Trimble Business Centre, AGTEK, Civil 3D, etc.), but their outputs are only as good as the information you feed them, and topo data from clients (if any) can often be wildly inaccurate.

Getting your own surveys is the best way to trust the data. However, surveyors are expensive and busy. It can be hard to justify their cost and, if you can, it can be difficult to get them on site when you need to. This all leads to adding a “fluff factor” to measurements of 5–10%. This approach may have been sufficient in the past, but it’s increasingly challenging to remain competitive using this methodology.

Today, you need accurate data to win bids, and you need to be able to collect it yourself. With a drone data analytics platform like Propeller, you can collect your own accurate data to produce high-quality, competitive submissions—and win more bids.


Ensure Your Data Is Accurate

Use Ground Control

To ensure you data is reliable and accurate when surveying with a drone means using appropriate ground control. There are two options:

  • Traditional ground control—Features or marked points recorded with a rover by a qualified surveyor.
  • Smart ground control (AeroPoints)—Solar-powered GPS units that use PPK to achieve survey-grade accuracy.

Since you work on multiple sites, it’s likely you’ll want to use smart ground control, so you don’t need to rely on anyone else to get your data.


Capture Your Data

Check out our series of blogs covering this in detail in various circumstances. But no matter the situation, the underlying concepts remain the same:

  • Ensure that your ground sampling distance (GSD) remains smaller than your desired survey accuracy.
  • Ensure you have 75–80% image overlap.
  • Avoid imagery of things you don’t need mapped (sky, distant objects, etc.).


Conduct Quick, Accurate Pre-Bid Surveys

It’s hard to overstate the importance of having data you can rely to produce accurate bids. Because drone surveying is simple and nontechnical, you can do all your pre-bid surveys yourself and avoid the fluff factor. Cut out the cost and time of a third-party surveyor; there are no traditional “boots on the ground” needed.

Once you’ve captured your survey, you can process that data in an estimating platform to get all the info you need for the best bid. And with browser-based platforms like Propeller, clunky desktop software is a thing of the past. Propeller’s intuitive visualizations allow you to have a visual conversation with your prospective clients as well as your own team.

In addition to the measurement and collaboration tools we’ll talk about further down, platforms like Propeller also clean up your data for better useability. For example, removing vegetation, vehicles, buildings, and other obstructions above bare earth take just one click on the corresponding filter. (If you’re processing it yourself, this is where a lengthy process of trial and error begins.)

terrain filtering on the Propeller Platform
Propeller’s filters at work removing a conveyor belt. The right panel shows an original image used to build the model on the left. Contour/Heatmap has been been switched on to show the change (or lack thereof) in elevation.


Use Design Surfaces and Linework Overlays To Avoid Unnecessary Import/Export

Propeller allows for easy uploads of design surfaces and linework. If a site’s design surface is accurately georeferenced, you can load it into the Platform and do a comparison against your initial topo to see how much you’d need to bring in or take out to hit the final design. For linework, you can easily measure a specific section of the site by turning linework into annotation boundary (see below).

Reliable and instant earthwork volumes allow you to see how much you need to import or export to get the job done. Knowing these exact values up front means you can better balance your site.

In the picture below, you can see 37,460 cubes are needed. With that number, you can work on balancing your site by getting some or all of that material from another part of the site.

construction site estimates obtained using drones


Estimating Platforms Enable Easy Reporting

At the end of the day, you also need to be able to present your survey data in an understandable way. No one is going to trust bids they can’t make sense of. When you use drone technology for estimates, not only are you providing you clients with real-world imagery they can understand, you’re also simplifying reporting and analysis.

In a processing platform like Propeller, you can export PDF and CSV reports on all your survey data. These provide a paper trail for who did what work when and a useful reference when meeting with your own team or your clients.

Further, you can also grant platform permission to a client in so they can see the 3D survey in action themselves.


Drone Technology Improves Your Estimates and Your Workflow

Job estimates are always going to be a part of the industry, but the technology that produces them will, and has, improved. Drones and data processing platforms are simply raising the quality of the baseline for estimating. They put the power to measure a site is in your hands. Relying on a client’s suspect data or paying a third party to survey is no longer mandatory.

As we’ve seen, not only do estimates take less time with drone technology, they’re just as accurate as traditional methods. Incorporating a drone and a processing platform like Propeller into your regular workflow can save you money and help win more bids. It also provides detailed, easy-to-understand documentation, site visualization, and rock-solid numbers.

Terrain editing CTA
Read more:
How Drone Data Can Make Your Next Earthwork Project a Success
Improve Construction Site Management, Collaboration with Drone Mapping and Analytics
How 3D Drone Survey Data is Helping Cheshire Contractors Scale Their Business

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