Overhead is everything you don't put in the estimate.
Some costs are difficult and some are impossible to put in an estimate.
Rent for your office, electrical bill, your salary, your secretary.
These are in general fixed costs that you spend in a year wether you do any work or not.
How do you figure your overhead?
Take all the costs you don't put in an estimate (rent, secretary, van, tools, electric bill, repairs, licenses, etc). So let's say (for ease of example calculations) you come up with 20K
Then look at your total sales for last 12 months. (Again, for ease of calculation), let's say you come up with 100K.
So the first 20K out of that 100K has to go to overhead. Therefore you need the direct cost of the sales to be 80K just to break even.
So when you estimate an 80K project, you need to add 20K overhead which comes to 25%.
Therefore your overhead in percentage is:
"Overhead" DIVIDED by "Sales MINUS Overhead " MULTIPLIED by 100
In the example above would be 20K/(100K-20K)*100=25%
If the example above would be 10K overhead and 100K sales then the overhead percentage would be:
10K/(100K-10K)*100=11.11%
Why 11.11%? Because in order to get 10K out of the 90K job you need 11.11%.
A lot of companies look 10K-100K sales and say "overhead is 10%". But then the price for the job is only 99K so when they try to take 10% overhead back from sales it leaves the job with only 89K when the estimate was 90K
I am using a new software program and it is asking for overhead as a percentage of a project. I an newer in business and don't have statistical data for that yet. What would be a good "ball park" number to put in there.