The Difference Between Hot Press, Cold Press, and Rough Watercolor Paper

Section 1 of 3:

Hot Press Paper

Toward the end of the paper making process, hot press watercolor paper is sent through heated “calender rolls,” which compress the paper and add its final texture, or “tooth.” The heat in the calender rolls smooths out the paper the same way a clothes iron smoothes out a pair of pants, lending the paper a nice, smooth surface.^{[1] X Research source}

Hot press paper is highly compressed and has a smooth surface, so paint takes a bit longer to seep into hot press paper. This allows an artist using watercolors to move and manipulate paint on its surface for a bit longer before the paint becomes permanently absorbed. An artist might even lift the paint off the paper with a bit of paper towel if they applied too much!^{[2] X Research source}
That said, paint tends to dry faster on hot press paper, which means an overall shorter period in which the paint is workable.^{[3] X Research source}

Advertisement

Hot press paper is more dense, so paint tends to absorb straight down into the paper, rather than spreading out across the surface of the paper. This makes for cleaner edges and more predictable and manageable paint spreading.^{[4] X Research source}

Since hot press paper is so smooth, pigments sit closer to the surface of the paper, rather than absorbing deeply. On top of that, the flat surface reflects more light, causing the colors to appear more intense.^{[5] X Research source}

Advertisement

Section 2 of 3:

Cold Press Paper

Cold press paper is also sent through calendar rolls, though as opposed to hot press paper, these rolls aren’t heated. In addition, the rolls apply less pressure to the paper. This lighter pressure and lack of heat allows the paper to keep its bumpy surface.^{[6] X Research source}

Cold press paper is sometimes referred to simply as “Not,” which means “Not pressed” or “Not hot pressed.”^{[7] X Research source}

“Rough” watercolor paper is another form of cold press paper, but is pressed at a lower pressure between sheets of felt to create an even bumpier surface.^{[8] X Research source}

This allows for more paint layering, since paint absorbs more easily into cold press paper. You may be able to achieve deeper, more complex colors by painting over a section more than once, or painting over one section with a different color.^{[9] X Research source}

The less-dense nature of cold press paper means that paint can travel more easily through the fibers of the paper. This means paint not only goes down into the paper, but also spreads or bleeds across the paper, which makes for a more typical “watercolor look.”^{[10] X Research source}

In addition, the bumpy surface of cold press paper allows the brush to graze across the paper, creating an uneven, textured appearance, which are great when painting watercolor landscapes.

Cold press paper is also great for wet-on-wet techniques, which provide softer edges.

Cold press paper can generally absorb greater quantities of paint and water before it begins to warp or tear.^{[11] X Research source} This makes cold press paper great for artists who like to saturate their paper with a lot of paint, or who work with a heavier hand.

Advertisement

Section 3 of 3:

Choosing Watercolor Paper

Hot press paper’s smooth surface makes it more similar to other kinds of art paper, like sketch paper, so it tends to work well with a number of mediums, like pencils, markers, pastels, etc. That also means it can showcase harder edges and sharper details. Opt for hot press paper if you plan to use more than just watercolor paints in your project.^{[12] X Research source}
Though hot press paper is similar to other papers, it can still absorb and hold plenty of water, unlike regular printer paper, which buckles when wet.

Cold press paper’s textured surface lends it quite a bit of visual interest—the peaks and valleys of the paper cause paints to settle in a more interesting, organic nature, which many watercolor artists prefer.^{[13] X Research source} It also absorbs more paint, allows for softer edges, blends more easily, and is more durable than hot press paper, so it’s considered much more forgiving for beginners when they’re first approaching watercolor painting.^{[14] X Research source}

The third kind of watercolor paper is rough paper. It’s similar to cold press, but has an even rougher surface, hence the name. This surface means you’ll get more absorbency, even softer edges, more intense texture, and more dramatic brush effects. That said, it’s more difficult to work with than cold press paper.^{[15] X Research source}

Watercolor paper weight is measured in “gsm,” or grams per square meter. The higher the gsm, the denser the paper, and the more liquid the paper can absorb before it begins to deteriorate. Most watercolorists prefer 300gsm paper, but choose a higher gsm if you plan to use more paint, or a lower gsm if you have a lighter hand.^{[16] X Research source}

Watercolor paper tends to come in 3 materials: wood pulp, cellulose fibers, and cotton. Wood pulp paper is generally considered lower quality, while cellulose paper may vary greatly in quality, but is often more affordable. Cotton watercolor paper is considered the standard—it’s sturdy, consistently textured, and holds paint well.^{[17] X Research source}

Some papers may have a low (or acidic) pH, which can deteriorate both the watercolor paint and the paper itself over time. It’s best to choose an acid-free paper, or a paper with a high pH (often indicated on the packaging label) so that your artwork has a longer lifespan.^{[18] X Research source}

Advertisement