Variables in Estimating Paint Jobs

I frequently receive phone calls and e-mails from someone wanting a “ballpark” price for their painting project. They usually give me the size of their house and think that this will be sufficient for me to provide a price. However, there are dozens of variables that must be identified and considered, and the size of the house is not one of them.
I can understand why a home owner might think that pricing is based on square footage. Many painting contractors actually price their work that way. However, unless we are painting the floor, the square footage tells me nothing about the work that needs to be performed.
As a simple example, consider a room measuring 20 feet by 20 feet, or 400 square feet of floor space. Assuming 8 foot ceilings, the walls have 640 square feet of surface area. Four rooms measuring 10 feet by 10 feet would have the same floor area. However, the wall area would be 1,280 square feet. Despite an identical floor area, the smaller rooms would require twice the labor and materials. And if the ceilings in the smaller rooms are 10 feet high, there would be another 320 square of walls to paint. In short, the area of the floor doesn’t provide an accurate measure of the area that will be painted.
Similarly, the floor area provides no information about other surfaces or their condition-the type and quantity of doors, windows, moldings, etc. It doesn’t indicate the height of the ceilings or the type of texture. It doesn’t tell me what repairs or prep will be required. All of these variables, as well as others, must be considered when pricing a painting job.
All things being equal, a painter should be able to perform the same task in approximately the same amount of time on every job. If it takes him 30 minutes to paint a particular type of door at Mr. Green’s, it should take him 30 minutes to paint the same type of door at Mrs. Brown’s. If the estimator knows how long it takes to perform a task, he can generate an accurate estimate by identifying the tasks required and the quantity of each task.
Of course, all things are seldom equal. The door at Mr. Green’s may have more peeling paint than the door at Mrs. Brown’s. Her entry may be two stories high, while his is only one story. Mr. Green may want his walls and ceilings to be the same color, while Mrs. Brown wants white ceilings and forest green walls. These variables will impact the labor required, and thus have an impact on the price.
Because of the variables involved, equally sized homes may require a vastly different amount of labor and materials. And this should be reflected in the price.
When I have explained this to a caller or e-mailer, I am often told that no prep is required, that the doors, windows, and texture are “standard.” However, in this context there is no such thing as standard. A typical house usually has different kinds of doors. And there are nearly a dozen different types of texture common in the Houston area.
It would certainly be easier to give estimates without looking at the job site. But that would be a disservice to everyone involved.