To estimate an interior paint job, one must consider the cost of paint, the square footage to be covered, other painting supplies needed, the labor costs if one is hiring painters and any special needs of the specific job. With this information in hand, one can calculate the costs of the job or use a job cost estimator to produce a final estimate.
Certain paint jobs pose special difficulties which must be calculated into the final cost estimate. If a dark wall is being painted with a lighter color, more coats are needed. Detailed trim, such as moldings, baseboards and wainscoting, take extra time, causing labor costs to go up. It's important to remember to include the ceiling in the square footage to be painted and to ascertain whether primer is needed on all walls. Paint costs range widely depending on the quality and brand of paint being used, with 1 gallon of paint typically needed to cover 350 square feet.
Labor costs also cover a wide range. Difficult jobs may require a skilled professional painter, while simpler ones can often be handled by a handyman who is likely to charge quite a bit less per hour. Once all the labor and materials costs have been gathered, the calculations can be made as to how much paint and primer is needed, what supplies are needed, and how many hours of labor are needed to complete the job. Online job cost estimators exist that allow a contractor to plug in these numbers and get a final estimate.