To calculate how much paint you need, multiply the room's total perimeter by its height to find the surface area, subtract non-painted spaces, and divide by the paint's spreading rate.
Use a measuring tape to find wall height and width, then multiply to get the area in square feet. Do this for each wall, add them up, and use the paint coverage per litre to estimate needs. For example, with 1 litre covering 100 square feet, a 20-litre paint bucket will cover around 2000 square feet.
Paint usually is applied at 350 to 400 square feet per gallon (primer at 200 to 300 square feet per gallon). Use the Area section below to calculate the walls and ceiling values.
For a standard 12x12 room with 8-foot ceilings, you will need approximately 2 gallons of wall paint (to cover two coats), 1 gallon of ceiling paint, and 1 gallon of trim paint.
A standard gallon of Sherwin-Williams paint typically covers 350 to 400 square feet. However, this can vary based on surface porosity, application method, and texture.
For a standard 10×10 room with 888-foot ceilings, you will need 2 to 3 gallons of wall paint (assuming two coats) and 1 gallon of ceiling paint. A good rule of thumb is that 1 gallon of quality paint covers 350350350 to 400400400 square feet.
Paintbrushes provide precision and control for cutting in corners and detailed trim, while rollers cover large surfaces like walls and ceilings quickly with an even layer of paint. Most professionals use both: using a brush for edges and tight spots, then a roller for the main open areas.
Red is universally considered the hardest paint color to cover. Vibrant red pigments are highly transparent and inherently prone to bleeding through subsequent layers. Other notoriously difficult colors to cover include black, dark blue, dark green, and bright yellow.
Standard coverage is roughly 350-400 sq ft per gallon with most interior paints, depending on the texture and color change. Did you measure the square footage yet? 2 gallons per room or 3 per 2 rooms. 8x8.
The average cost to paint the interior of a house is $2,022, with a total range of $350 to $5,800, depending on your area, type of paint, and square footage. The biggest factor affecting your cost is home size, as you'll pay between $2 and $6 per square foot.
A one gallon (3.70 liter) can of wall paint covers about 375 – 400 square feet (35 to 37 square meters). Calculate one room at a time and determine if you need 1 or 2 coats. One (1) coat of premium paint will cover most surfaces when you are painting over a similar color.
To calculate the square footage for painting, multiply the wall's width by its height, add all walls together, and subtract the square footage of unpainted areas (doors and windows).
Superior Coverage Through Layering Thin coats allow you to build color gradually and strategically. Each layer fills in microscopic gaps the previous coat missed, creating genuinely complete coverage. The cumulative effect actually hides better than one thick application ever could.
You generally don't need to prime if you are painting over an already painted wall that is in good condition. However, you must prime if you are dealing with bare drywall, raw wood, major color changes (like dark to light), glossy surfaces, or stubborn stains.
Top 10 Timeless Paint Colors for Your Home
There are three main types of “impossible” colors: Forbidden colors. These are colors our eyes simply cannot process because of the antagonistic way our cones work, for instance “red-green” or “yellow-blue.”
Cool gray is being replaced by "mushroom" neutrals (warm taupes and greys with subtle green or violet undertones), warm earthy khakis, and soft, natural sages.
Professional Painter Prices. Most professional painters charge $2 to $6 per square foot of paintable area. Less commonly, they'll charge anywhere from $20 to $50 an hour. In some areas with high costs of living, you might even pay upwards of $100 an hour.
Weather considerations are key to ensure proper paint adhesion and drying. It's important to pay attention to temperature guidelines to avoid any issues. Seasonal painting tips recommend early summer and early fall as ideal times for painting due to favorable weather conditions.
How can you tell if an interior paint job is bad?
Whether painting walls at home or working on an artistic canvas, the most common mistakes revolve around rushing preparation and misusing tools. By far, the biggest error is skipping surface preparation. Failing to clean, sand, or repair holes ensures peeling, poor adhesion, and a lackluster finish.
While it does take some setting up, painter's tape is the most effective way for painters to create straight lines. Whether cutting in or making an isolated line, painter's tape can create a straight line on almost any surface.
Professional painters use both methods, often employing a hybrid approach. They spray for speed, flawless finishes, and hard-to-reach areas, but they roll for better paint adhesion, easier touch-ups, and in furnished spaces.