How to Estimate a Contract House Painting Job

House painting can be a lucrative job, but knowing how to estimate is critical. Bidding too high for a job will knock you out of the running, while estimating too low can actually cause you to lose money in the long run. Proper estimating requires practice, but following a step by step process on each job can shorten the learning curve.

Note the condition of the existing surfaces. Is the paint peeling? Will you need to remove wood stain? Are the walls dirty? Do you need to pressure wash the siding? Also consider the difficulty of reaching areas that will be painted. Do you have enough room to comfortably maneuver ladders? Do you need to rent scaffolding? Are there furniture pieces that cannot be moved? Will you need to work around children or pets? Is the home excessively dirty?

Walk the job site and take detailed measurements of everything. Walls, ceilings and floors are measured in square feet, while windows and trim are measured in linear feet. To get the square footage of a wall, multiply the length by the height. To calculate linear footage, measure the length of each piece and add them all together.

Discuss the client's expectations. Some homeowners may offer to help you work in exchange for a better price. Some prefer to provide the materials, such as paint and rollers. Some expect you to repair damage, while others prefer to take care of repairs separately, before you begin painting. Discussing expectations in advance helps you know what to expect, making it easier to create a fair estimate.

Visit the job site. Potential customers will call frequently to ask for your "average price" on a painting job. There is no such thing as an "average job," as each location has different measurements, different layouts and various factors that may affect the difficulty of the job. Never estimate a job over the phone.

Consult your notes to determine a difficulty factor for the job. It is common to mark up particularly tough jobs from 10 to even 100 percent. Likewise, if the job is particularly easy or is simply something you really want to take, pricing it down by 10 or 20 percent is common. Be careful not to bid too low.

Use a written painting price guide to calculate a base rate for the project. Price guides are available online, but be sure to use one for your state. The average price for painting jobs varies dramatically between locations. Most price guides include the cost of materials. Add up the prices for each type of painting (walls, ceilings, trim, floors, etc.) separately. Take into consideration the number of coats of paint you plan to use as well as a primer coat if you plan to use primer. Add roughly 20 percent to your total to account for erroneous measurements or small tasks that may not have been included.

Difficulty: Moderate