Painting Estimates That Protect Your Margins
The fastest way to lose money on a paint job is to bid the paint. The paint is the cheap part. A professional painting contractor estimate is mostly a labor document, and the labor that decides whether you make money is the labor nobody sees: the scraping, sanding, patching, caulking, and priming that happens before a finish coat ever goes on.
Why painting is a labor business, not a paint business
Painting is the trade where the materials lie to you. On a typical repaint, paint and supplies run about 15 percent of the job and labor runs the other 85 percent, per HomeAdvisor's cost data. That ratio is the whole game. A gallon of good paint costs $25 to $50 and covers around 350 square feet, so the homeowner who priced paint at the store thinks she knows what your job costs. She is pricing the 15 percent. A painter outside Spokane told us he bid a 1950s exterior at $2.25 a square foot, clean and competitive, then spent three days scraping and priming chalked, peeling siding before a finish coat went on. The paint came in right on budget. The labor blew the job apart. He did not lose money on paint. He lost it on the hours the square-foot number never counted.
Here is a take that will annoy half the painters reading this: per-square-foot pricing is fine for the homeowner and dangerous for you. It prices the area you have to cover. It says nothing about the condition of what you are covering, and condition is where the labor lives. The painting contractors we work with who stay in business quote the prep and the paint as two different things, because they are two different things.
What per square foot leaves off a painting contractor estimate
A square-foot rate measures the wall. It does not measure the wall's history. Two rooms of identical size can be a four-hour job and a two-day job depending on what is already on the surface. Bare drywall needs a primer plus two coats. A dark wall going light needs a tinted primer and maybe three coats. Glossy old trim needs sanding and a bonding primer, or the new coat peels inside a year. None of that shows up in the square footage. Interior repaints run about $2 to $3 a square foot, with the overall range across surfaces landing between $2 and $6, per HomeAdvisor, and the spread inside that range is almost entirely condition and detail, not area. Cut-in alone, the slow brushwork along edges and ceilings, can eat a third of the interior labor and never appears in a wall-area calculation.
"I stopped quoting paint jobs and started quoting prep jobs. The paint line is the easy part. The day I put scraping, sanding, and priming on their own lines, two things happened: I stopped eating prep hours, and clients stopped arguing about the total. They could finally see what they were paying for." — exterior repaint contractor, second-generation shop
That painter is describing the core move. The square-foot number is a starting estimate the homeowner can understand, not the bid that protects you. The bid is the document that names the condition, the coats, and the prep, and prices each one where it actually lands.
The lines painters keep burying in "paint the room"
The phrase that costs painters the most money is "paint the room." It bundles a dozen different labor items into one number the painter then has to honor. A professional estimate breaks them out: surface prep on its own line, then walls, ceilings, trim, and doors each priced separately, plus masking and floor protection and any ladder or high-ceiling work that slows the crew down. Spelling it out is not nickel-and-diming. It is the difference between an estimate the client reads as a plan and a number she reads as negotiable. Across the painting contractors using Jobkore, the saved estimate template that wins splits prep from paint and lists each surface as its own line, so a chalky exterior never gets priced like a clean drywall hang. The first job where the prep doubles teaches you to show the line. The template makes sure the next bid carries it.
The other half of the fix is the exclusions. A bid that says "assumes surfaces are in sound, paintable condition; significant rot, drywall repair, or failed substrate quoted separately" is not hedging. It is the line that turns a surprise into a change order instead of a loss. The siding that looked fine from the driveway and turned out soft at the corners is the homeowner's repair to pay for, but only if you wrote the assumption down before anyone signed.
The pre-1978 line that can cost you the whole job
If the house went up before 1978, there is a line on your estimate you cannot skip, and it is not optional. Under the EPA's Renovation, Repair and Painting rule, anyone paid to disturb painted surfaces in a pre-1978 home has to be lead-safe certified, train their crew, and use lead-safe work practices, and that applies to every firm including a one-person shop. This is not a formality. The certification, the containment, the slower controlled sanding, and the cleanup are real hours and real cost, and the fines for skipping them run into five figures per violation. A painter who bids a 1920s interior at the same square-foot rate as a 2015 build is not competitive. He is exposed. Price the lead-safe work as its own line, or pass on the job. There is no version of absorbing it quietly that ends well.
This is also the honest limit of per-square-foot pricing. On a clean, modern repaint with sound walls, a square-foot rate gets you close enough. On an old house with chalking, peeling, lead, and forty years of deferred maintenance, the square footage is the least important number on the page. The age of the house tells you more about the labor than the size of it ever will.
Re-price the condition, not the square footage
If you do one thing this week, pull your last three repaint bids and the actual hours they took. Find the one that ran long. Then look at what you priced: did you bid the square footage, or did you bid the condition? Almost every blown paint job traces back to prep that got bundled into a wall-area number. You do not need software to see it. You need to put prep on its own line on the next bid and watch what happens to the argument about the total, and to your margin.
Paint is the last thing that happens on a paint job and the first thing everyone prices. The painters heading into the back half of 2026 with their margins intact, even as paint prices climb again, are the ones who figured out that the brush is the cheap part. The estimate that protects you is the one that charges for everything that happens before the lid ever comes off.
Frequently Asked Questions
How do painters charge, per square foot or per hour?
Both, and the smart ones combine them. Per-square-foot pricing works for clean, standard repaints because it is fast and easy for a homeowner to compare. Prep-heavy or unpredictable jobs get priced by the hour or with prep broken onto its own line, because square footage measures area, not the condition that drives the labor.
How much does it cost to paint the interior of a house per square foot?
Interior repaints run about $2 to $3 per square foot, with the overall range across surfaces landing between $2 and $6, per HomeAdvisor. The spread is almost entirely condition and detail, not area. Adding ceilings, trim, and doors pushes toward the high end because each surface is its own labor at its own pace.
How many coats of paint should a contractor quote?
The standard quote is one primer plus two finish coats. Bare drywall, porous surfaces, and dark-to-light color changes often need a tinted primer and a third coat. Spell out the number of coats on the estimate. Quoting two coats on a job that needs three is one of the most common ways painters lose margin.
Why does prep work cost so much on a paint job?
Because painting is roughly 85 percent labor, and prep is the hidden half of that labor. Scraping, sanding, patching, caulking, and priming take real hours and produce nothing the client can see, so it is the first thing painters underbid. The condition of the surface, not its size, decides how many of those hours the job needs.
Do I need to be lead-certified to paint an old house?
Yes, if the home was built before 1978 and you are paid to disturb painted surfaces. The EPA Renovation, Repair and Painting rule requires firms to be lead-safe certified and to use lead-safe work practices, and it applies to every firm including sole proprietors. The certification and containment are real cost and belong on their own line.
