When estimating paint coverage, it is important to consider whether the coverage includes one or two coats of paint. The answer depends on several factors related to the specifics of the painting project.
What is paint coverage?
Paint coverage refers to the area that can be covered using a gallon of paint. It is usually measured in square feet per gallon. Paint coverage depends on the type of paint, the surface being painted, and the application method.
When a paint manufacturer provides coverage information for a particular paint, they are referring to the amount of area that can be covered with one coat of that paint applied at the recommended film thickness. The recommended film thickness varies based on the type of paint.
Factors affecting paint coverage
There are several key factors that impact the coverage that can be achieved with one gallon of paint:
- Type of paint – The ingredients, viscosity, and solids content varies for different paints. Higher quality paints with more solids will provide better coverage.
- Surface – Rough or porous surfaces require more paint than smooth surfaces to achieve full coverage.
- Color – Darker colors often require multiple coats to fully cover.
- Application method – Brush, roller, or spray application affects coverage.
- Film thickness – Manufacturer specs are based on standard thickness; applying paint too thin reduces coverage.
Does coverage include one or two coats?
The advertised paint coverage is for one coat applied at the recommended film thickness. It assumes proper surface preparation and application method.
In most cases, two coats are recommended and required to achieve complete hide and the desired look. The first coat acts as the primer and seals the surface. The second coat provides the finished appearance.
Since the coverage claim is for one coat only, you cannot just double the square footage to get the coverage for two coats. The reason is that the first coat will absorb differently depending on the porosity of the surface, leaving less paint available for the second coat.
Estimating coverage for two coats
There are a few general rules of thumb to estimate the coverage for two coats:
- First coat covers 80% of the advertised coverage.
- Second coat covers the remaining 20%.
- Therefore, two coats will cover approximately 60% of the advertised coverage.
For example, if the paint is rated for 400 sq ft per gallon coverage with one coat, for two coats you can estimate:
- First coat will cover 80% of 400 sq ft = 320 sq ft
- Second coat will cover remaining 20% = 80 sq ft
- Total for two coats is 320 + 80 = 400 sq ft
So the coverage for two coats would be 60% of the advertised one coat coverage, which is 240 sq ft per gallon in this example.
When is one coat enough?
In most cases, two coats of paint are recommended to provide complete hide and coverage on the surface. However, there are some exceptions where one coat over a properly prepared surface may be sufficient:
- Repainting a surface that is already painted with a similar color paint
- Using a primer + paint in one product over bare drywall
- Painting a dark color over existing dark colors
- Painting high quality paint over a properly prepared smooth surface
Even in these cases, two coats are usually preferred whenever possible to get a more even, consistent appearance. One coat often looks streaky or uneven compared to two coats.
Tips for maximizing paint coverage
To get the most coverage from your paint, here are some tips to follow:
- Properly prepare surfaces – Clean, sand, patch, and prime as needed
- Use premium quality paints with higher solids content
- Apply an appropriate primer for the surface
- Use the recommended film thickness – Do not overspread the paint
- Maintain a wet edge and work quickly to avoid lap marks
- Use high quality applicator tools – roller covers and brushes
- Apply paint adequately over grooves, corners and edges
Conclusion
The advertised paint coverage is for one coat only. Most painting projects require two coats to achieve full coverage and a uniform appearance. As a general rule of thumb, two coats will provide approximately 60% of the quoted coverage per gallon. However, with good preparation and application, it may be possible to get closer to the full advertised coverage when applying two coats.