One of the most frequently overlooked misjudgments that developers make when preparing a site for development is the volume of materials. This number is important Dirt haul off refuse goes hand in hand with the amount of dirt and inaccurate estimates can negatively impact schedules and project budgets substantially.

Volume estimation goes beyond simply measuring the footprint of a proposed excavation. Experienced estimators adjust for the differences in depth; for compaction; and for existing site topography, as well – and do it much more accurately than rough guessing from surface area alone.

Why simple surface measurements fail.

A typical error is to estimate the volume of excavation required from the horizontal area of a proposed cut, without taking into consideration any depth changes across the site. The Houston area is comprised of much rolling terrain, resulting in varying depths in different areas of a site.

The following are factors that make simple estimates of volume difficult:

Current uneven grade throughout the property.
Different levels of excavation for various building components
Soil compaction difference between natural and disturbed soil.
Not seen from the initial surveys – conditions under the surface that are not visible to the naked eye.

Improving accuracy with professional surveys.

Genuine site engineers or surveyors will provide a much better best estimate of the volume to any developer working with them than a cursory estimate made from looking at a site. These experts can estimate the estimated cut/fill volumes based on the detailed topographic data and the specified plans for excavation with a far greater amount of accuracy.

The cost of this initial work to properly ascertain the quantity of materials can be more than mitigated by the cost of overruns and schedule surprises resulting from vastly underestimating the quantity of materials needed once digging starts.

The reason for Soil Expansion to be included in calculations.

A few things that may surprise a developer is dealing with soil expansion during excavation. The ground is usually more compacted than the soil when it is loosened by digging. This results in the quantity of material to be removed may actually be greater than the volume of the excavation hole being removed.

A seasoned hauling company and excavation contractor will normally take this expansion into account with their quotes and this will help prevent situations of having far more trucks than should be required based on the hole size alone.

This is a Practical Estimation Process.

The developers who are approaching a new project will surely get advantages from following a structured estimation procedure:

Acquire correct topographic surveying data on the site.
Determine desired excavation depth for various areas.
Consider soil expansion factors when removing.
Talk with hauling companies about reasonable truck and trip estimates

How Communications With Hauling Providers Help

When survey information and project plans are shared early in the planning process, with the hauling provider, they can provide more accurate scheduling and cost estimates. Providers who have worked on projects of similar type may be able to spot some volume or schedule problems that do not show up in the surveys.

This integrated approach often yields more accurate estimates than the developers can make if they do the work themselves without engaging the team that is in charge of the removal logistics.

When estimates are very far off, what happens?

If the volume is underestimated, it may cause scheduling scrambles in the middle of the project, when extra trucks have to be scheduled last minute based on the unexpected material. Underestimating, which is less disruptive, may be a waste of budget or cause an unnecessary overstate of schedule by using more trucks than any project needs.

Whether it's the first scenario or the second, it's inefficient, so getting the estimate right at the beginning of the project is crucial when it comes to project planning for a development with substantial excavation.

Final Thoughts

The key to good dirt haul off planning is accurate volume estimation. Those who thoroughly research an area and take soil expansion into consideration, as well as maintain open communication with hauling companies, are more likely to prevent budget surprises and scheduling scrambles that can result from taking an educated guess with the lack of enough data on site.

What Should Developers Know About Estimating Dirt Haul Off Volume Accurately?