Demolition Formula – Calculating Supplies, Tools & Time Needed
In this guide, we’ll be providing a demolition formula for calculating the amount of time and supplies needed for a typical demo project.
Structural demolition is one critical sector of the construction industry that involves teardown. Here, old buildings, as well as defective structures, are pulled down for further expansion.
Also, partial demolitions may be necessary for remodeling purposes.
So, is there a demolition formula involved?
There is! Certain basics cannot be ignored or left out when it comes to matters of demolition. These include the size of demolition, the dumpster requirements for a demolition project as well as the time needed for completion.
These are key considerations involved in working out the formula.
Calculating Size of Demolition
Here, you’re seeking to arrive at an estimate for the volume of debris to be produced from demolition.
Let’s be clear. Knowing the size of the demolition project doesn’t give you the exact amount of debris produced. It’s rightly called an estimate because that’s what it is.
Nevertheless, you get a remarkably close idea of what to expect. So, in calculating the size of demolition, the main formula used multiplies the area’s length (in feet) by its width and height all in feet.
The result obtained is multiplied by onethird and further divided by 27.
The figure obtained translates to the cubic yards of debris to occupy a dumpster. So, in making things plain, you have a formula that goes as follows; (Length (ft) x Width (ft) x Height (ft) x 1/3) /27.
Remember, this formula is required to help estimate the volume of debris.
Explaining Demolition Formula
Asides from the formula provided, being able to translate such into reallife demolition jobs is essential. Here, you’ll need to consider the size of the area, the airspace as well as the cubic yards.
For many, these are plain jargon without further explanation. So, let’s consider each as follows;

Size of the Area
The size of the area won’t mean much without focusing on the basics of measurement such as the space dimensions. To arrive at this, you’ll need to consider the blueprints of such a structure.
You can also proceed to measure size by calculating the dimensions in feet.
So, you’ll need to consider the number of intersecting walls as well as the number of floors. The figure obtained can easily be worked into your formula. A professional demolition contractor knows exactly what to include.
As such, figures aren’t difficult to work out.
Because a trained eye knows exactly what to include, it’s best to have a pro perform your estimation. Also, you have the opportunity of making all necessary inquiries.

Airspace
In looking at the demolition formula used in determining debris volume, you’ll find out that there’s a onethird component to the equation. To explain such, you’ll have to consider the airspace within rooms.
That is the space between the floor and ceiling as well as that between walls.
Such space needs to be taken into consideration; hence it’s being designated with a simplified number represented by onethird.
So, when the formula is fully worked out, you arrive at a very close estimate of the actual debris volume produced.

Cubic Yards
It’s important to use cubic yards as a yardstick for calculating the volume of debris generated because that’s the measurement for most dumpsters. Now, there are about 27 cubic feet in a cubic yard.
With this, you have a fair idea of the right dumpster size to get for your demolition project.
Dumpster Requirements For A Demolition Project
Demolition projects can be limited or extensive.
Depending on the scope of demolition, you’ll have to determine the right dumpster size that best suits your needs. Now, there are several dumpster sizes to choose from.
These range from the smallest to the largest.
That is 10yard dumpsters, 12yard dumpsters, and 20yard dumpsters.
Other sizes include 30yard dumpsters and 40yard dumpsters. Without proper estimation, you might end up renting a dumpster that’s too small or large for your demolition project.
This is where your demolition formula comes under focus. With the formula provided above, you’re able to work or find out the estimated volume of debris to be produced.
This gives you a better idea of what to get for your demolition needs.

Number of Dumpsters To Demo A House
Home or building demolition jobs are pretty large when it comes to the volume of debris produced. To put things into perspective, a single 40yard dumpster won’t be enough to contain all the debris at once.
In other words, you’ll need multiple 40yard dumpster loads to hold such debris.
Speaking of the number of dumpsters required, getting such won’t be possible without considering the house size. Now, building size will range anywhere from 1,000 sq. ft. to about 3,000 sq. ft.
The building size determines the debris produced.
A 1,000 sq. ft. house will produce about 135 cubic yards of debris. Wondering how this was arrived at? Simply refer to the formula provided above. 135 cubic yards of debris will fill into about 3.5 40yard dumpsters.
A building twice the size (that is 2,000 sq. ft.) produces about 270 cubic yards of debris. You’ll need about 6.75 40yard dumpster loads to hold such.
A house measuring 3,000 sq. ft. in size will produce about 405 cubic yards of debris when demolished. This translates to around 10.5 40yard dumpster loads of debris.
The figures will be much different when using smaller dumpster sizes.
However, there’s no point going for smaller dumpster load sizes when dealing with house demolition jobs. 40yard dumpsters limit the number of trips to the dumpsite.
Estimating Time Required For Completion
There are different types of demolition jobs. Each type takes a certain amount of time to complete. For example, complete demolition jobs take lesser time to complete than partial demolition.
Also, deconstruction takes much longer to complete than full demolition.
While working with a demolition formula gives you an estimate of debris produced, it has no impact on completion time. The time for completion largely depends on the methods used.
This solely rests on your preferences. That is, whether you wish to salvage useful components or not.
The demolition formula is a basic requirement for calculating debris among other things. While demolition jobs can be handled as DIY projects, it’s best to allow skilled professionals to handle major demolition jobs.