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How much does a gallon of paint cover?

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You’ve finally landed on the perfect color for your next painting project. Now, you’re probably wondering how much paint to buy. First, you’ll need to understand paint coverage so that you can get your interior paint estimate right.

Every room has its own quirks that impact how much a gallon of paint will cover. Things like the condition, texture and porosity of your wall surface can make a difference in how much paint the walls will soak up. Below are the general paint coverage guidelines to follow, assuming your walls are in good condition, plus some things to keep in mind in those quirky edge cases.

Paint Coverage 101

  • One gallon of Wall Paint will cover approximately 375-425 square feet.

  • One gallon of Trim Paint will cover approximately 375-425 square feet.

  • One gallon of Ceiling Paint will cover approximately 350-400 square feet.

  • One gallon of Primer will cover approximately 225-275 square feet.

** These estimates approximate and coverage amounts may vary depending on the condition of your wall or surface.

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Special Circumstances that Impact Paint Coverage

Fresh Drywall

It might surprise you, but a fresh canvas is not necessarily the most efficient one. Fresh drywall is very porous and will soak up much of your paint so priming drywall with at least two coats first is a must. Granted, most drywall will be pre-primed or even painted by the time you get to it, but if you’re replacing drywall after a leak, for instance, or working on a newly renovated space, factor in an extra coat or two of primer to be sure your surface is well-prepped.

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Our fast-drying, multi-surface paint primer applies easily to conceal imperfections and block stains while providing a long-lasting bond to a variety of interior surfaces. It’s the foundation for a flawless paint job.

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Textured Walls

A textured wall means more surface area, which means you’ll need more paint to cover it. Think stucco, brick, popcorn ceilings,or similar surfaces which have more surface area to paint. We recommend buying 20 percent more paint for a textured surface (so, if you are painting a 100-square-foot room, account for 120 square feet).

Dramatic Color Changes

If you want to make a dramatic color change, like black to a light neutral, it’s typically going to require extra coats paint to cover up that super dark color with full opacity. Using primer will help help this much easier and cut down on the number of coats it takes to cover up a dark color.

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Calculating How Much Paint to Buy

Now that you know the basics of paint coverage, here’s how to figure out exactly how much paint to buy — no matter the size or layout of your space.

  1. To get started, multiply the width times the height of each wall in your space. Voila, you’ve got your square footage.
  2. Next, calculate the square footage of each window and door, or any other area that you’re not painting (like a wall niche or doorway), and then deduct that from the total square footage of your wall surface.
  3. Do the same for trims and ceilings, multiplying the length times the width to get the square footage, then check out our coverage amounts for each type of paint below to figure out how much you’ll need. Remember that each coverage amount is for two coats. If you paint one coat and feel like you’ve got good coverage, awesome! But for the most professional look, we always recommend two coats.

Not into math and just want a general paint estimate? Look no further - we’ve created a handy paint calculator to do all the work for you.

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