One-Coat Coverage: Myth Or Reality?

One-coat coverage is a term used by paint manufacturers to describe heavy, thick acrylic-latex interior and exterior paint that builds up high. One-coat paint promises to cut down the time and labour of applying primer or multiple coats of paint. It is up to 20% more viscous than ordinary paint, which usually requires two or more coats. However, one-coat coverage is not guaranteed, and it is still best to apply two or more coats if possible.

One-coat paint is up to 20% more viscous than ordinary paint

One-coat paint is a term used by paint manufacturers for heavy, thick acrylic-latex interior and exterior paint that builds up high. One-coat paint is up to 20% more viscous than ordinary paint, meaning it has a higher resistance to spilling. This is due to the friction between its molecules, which move at different speeds and collide with each other, making motion difficult.

One-coat paint is generally divided into two categories: specialty coatings and decorative coatings. Specialty coatings are designed to repair severe problems such as stained or water-flooded walls, and are usually available in a few variations of white. On the other hand, one-coat decorative coatings are not aimed at disaster repairs but instead at reducing painting time. They offer a broad selection of colours.

One-coat paint is not a guarantee that only one coat will be needed. Manufacturers' guarantees often exclude repaired surfaces, porous surfaces, uncoated surfaces, surfaces that contain tannins (such as cedar), and surfaces with aggressive stains.

One-coat paint is best used on low-traffic surfaces, like the walls in living rooms, dining rooms, bedrooms, and hallways. Kitchens and bathrooms are the most difficult rooms in the home to paint because they are regularly subjected to high levels of moisture and rapid temperature changes.

One-coat paint is not suitable for porous surfaces

One-coat paint is a heavy, thick acrylic-latex paint that is designed to eliminate the need for multiple coats of paint or primer. It is up to 20% more viscous than ordinary paint, and is suitable for both interior and exterior use.

However, one-coat paint is not suitable for porous surfaces. This is because the porous nature of some surfaces can result in the moisture element of the paint being sucked into the surface on initial application. This can lead to a patchy, uneven finish.

Surfaces such as bare plaster, drywall, interior brickwork, bare wood, and MDF are all porous and can be problematic for one-coat paint applications. For example, drywall is like a sponge and can create an uneven drying appearance if not primed first. Fresh plaster is another surface that can cause issues without priming, as it tends to pull pigments from anything it touches while curing.

To avoid a patchy finish on porous surfaces, it is recommended to seal the surface with 2-3 coats of a finishing coat or primer before applying paint. Alternatively, a mist coat of paint diluted with 5-10% water can be applied first, followed by the recommended number of paint coats.

Therefore, while one-coat paint can save time and labour, it is not suitable for all surfaces. Porous surfaces require additional preparation, such as sealing or priming, to ensure a smooth and even finish.

One-coat paint is divided into two categories: specialty coatings and decorative coatings

One-coat paint is a heavy, thick acrylic-latex paint that contains up to 20% more paint solids than conventional paint. It is designed to eliminate the need for multiple coats of primer or paint, saving time and labour. However, it is not always guaranteed to be a one-coat solution, and is not suitable for porous surfaces.

Specialty Coatings

Specialty coatings are designed for emergency repairs and difficult surfaces. They are used to repair severe problems such as stained or water-damaged walls. These paints are usually available in a few variations of white, with some brands offering a limited number of tints. Examples of specialty one-coat paint brands include Zinsser Perma-White and Kilz 2.

Decorative Coatings

Decorative coatings, on the other hand, are aimed at reducing painting time rather than disaster repairs. They offer a broad selection of colours, unlike the limited white shades of specialty coatings. Examples of decorative one-coat paint brands include Behr Marquee and Sherwin-Williams Infinity.

While one-coat paint can be a convenient option, it is important to note that it may not always provide full coverage in just one coat, especially for extreme colour changes. Additionally, manufacturers' guarantees for one-coat paint often exclude certain surfaces, such as repaired or porous surfaces, uncoated surfaces, and surfaces containing tannins or aggressive stains.

One-coat paint is not a guarantee

Additionally, one-coat paint is typically divided into two categories: specialty coatings and decorative coatings. Specialty coatings are designed for emergency repairs and difficult surfaces, such as stained or water-flooded walls, and are usually available in only a few variations of white. On the other hand, decorative coatings are aimed at reducing painting time and offer a broader selection of colours.

Even in favourable conditions, one-coat paint is not guaranteed to be one coat. It is always best to apply two or more coats of paint if possible. This is especially important for exterior painting and high-impact surfaces such as door and window trim, bathroom ceilings, hallways, and kitchens. Multiple coats help to obliterate overlaps, smears, and lines, deepen the colour, and strengthen the paint.

Furthermore, while some one-coat paint brands do offer a "one-coat guarantee", this is often subject to certain conditions and exclusions. For example, Behr's "one-coat guarantee" excludes certain colours, uncoated or porous surfaces, woods that contain tannins, and surfaces with heavy stains.

In summary, while one-coat paint can be a time-saving option for certain projects, it is not a guarantee and may not always provide the desired level of coverage or durability. It is important to carefully read the manufacturer's instructions and exclusions and consider the specific surface and conditions before deciding whether one-coat paint is suitable for your project.

One-coat paint is best for low-traffic surfaces

One-coat paint is a time-saving alternative to traditional paint, which often requires multiple coats for full coverage. One-coat paint is thicker and contains up to 20% more paint solids than conventional paint, allowing it to build up higher and cover old coats of paint without a primer.

While one-coat paint can be used in various situations, it is best suited for low-traffic surfaces such as living rooms, dining rooms, bedrooms, and hallways. These areas typically require less protection and are more forgiving when it comes to paint jobs.

One-coat paint is not ideal for high-traffic areas, such as kitchens and bathrooms, which are regularly exposed to high levels of moisture and temperature changes. These areas require paint with higher water resistance and protection against mould and mildew.

Additionally, one-coat paint may not be suitable for new drywall or new wood projects, as they require a generous coat of primer and paint for adequate coverage. It is also important to note that one-coat paint may not provide full coverage when painting over a significantly darker colour.

When choosing one-coat paint, consider factors such as colour, texture, paint type, and additional features like water resistance or an anti-drip formula. It is also important to ensure proper ventilation when painting to avoid exposure to harmful volatile organic compounds (VOCs) present in the paint.

Frequently asked questions