17 Aug 2022Mont Marte

Confused about which watercolour paper to reach for? Can thick copy paper be used? And what’s a good GSM for watercolour anyway? If these questions are weighing on your mind, you’ve come to the right place. Here we’re answering our most commonly asked watercolour paper questions to clear up any confusion, before you dive right in.

Hand painting a pink flower using watercolour paints using Mont Marte watercolour paper.

1. What’s the gsm paper for watercolour paper?

GSM stands for ‘Grams per Square Meter,’ and it refers to both the thickness and weight of the paper. The higher the GSM, the thicker the paper. Standard copy/printer paper is usually around 80 - 100gsm, so you can expect watercolour paper to be thicker at around 180 - 300gsm.

2. What paper should I use for watercolour? Can I just use thick copy paper?

When watercolour paper is made, it’s also ‘sized’, meaning it has a gelatine covering either internally (in the production process) or externally (with a coat over the paper after it’s made). This covering reduces the water’s absorbency, plus it gives your watercolour a brighter look. How? because the pigment is being picked up by the gelatine which changes the overall coverage to look smoother. Copy paper doesn’t have this coating, so your pigment won’t have this smooth coverage. So, although a thicker copy paper might absorb the water you use, you’ll most likely have a patchy result instead, which isn’t fun at all.

Closeup of Mont Marte discovery watercolour paper stacked.

3. What is acid free paper?

You might have noticed the term “acid free paper” when browsing watercolour papers and if you’re exploring our range, you would have noticed this too. This is a good thing, added chemicals can cause the paper to degrade over time, so a quality watercolour paper will be “acid free”, to prevent the paper yellowing over time.

4. What’s the best watercolour paper for beginners?

If you’re just starting out, it’s likely you’ll be looking for an affordable option to have a play with. So rather than spending top dollar, something like our Mont Marte Watercolour Paper Discovery is a great watercolour paper for beginners. This 190gsm paper can keep up with all kinds of techniques, testing and all-round exploration. Otherwise, if you’re looking for something that’ll hold your pages securely, the Mont Marte Watercolour Pad Premium A3, is 180gsm. Its tape bound with a backing board and it features practical tips and techniques to help give beginners a helping hand. 

Flatlay of watercolour paper with brush and watercolour pan side by side with a purple background.

5. Can I draw on watercolour paper?

Yes you can draw on watercolour paper! You can use pencils, pen and ink, pastels (both chalk and oil pastels) and even paint with gouache or acrylics on watercolour paper too. What won’t work as well, would be oil paint, which can leave an oily mess so it’s best to skip out on using watercolour paper for that one. The exception to this is, oil pastels (because they’re made with less oil than oil paint). Watercolour paper is beautiful to draw on, so if you’re lucky enough to have some extra watercolour paper up your sleeve, you can add drawing on watercolour paper to your creative bucket list.

6. Can I draw or use watercolour on cotton paper?

If you’re wanting a more ‘lux’ paper, try the Mont Marte cotton watercolour paper range. We have a few options in our Artiste and Premium ranges, made from 100 per cent cotton, so you’ll get minimal shrinkage and more pigment absorption. The Mont Marte Cotton Watercolour Premium 300gsm paper has a rough tooth on one side and a medium tooth on the other side, so you can paint and draw on whichever you choose. Using watercolour on cotton paper is more costly than standard watercolour paper, but if you have the chance, it’s a joy to use.

Flatlay of watercolour paper with brush and watercolour pan side by side with a purple background.

7. What’s watercolour block paper?

Watercolour block paper has a gummed edge rather than being taped and the pages are mounted on a backing board. Not only do these pages not need to be stretched, but blocks will also stop pages from warping when wet. The Mont Marte 300gsm cotton watercolour paper is available in blocks, so it’ll keep your work together and the you won’t need to worry about your masterpieces bending, plus it’s made from 100 per cent cotton paper so it’s resistant to pilling. To remove a sheet from a block, grab a palette knife and pop it between the top and bottom sheet and gently slide it to remove the pages.

8. Do I need to gesso watercolour paper?

You won’t need to prime watercolour paper, unless you’re using acrylic paint and looking for more grip to the paper. If that’s the case reach for a gesso to prime your surface.

Hand adding the final touches to a Betta fish watercolour painting using watercolour tubes.

9. What does stretching watercolour paper mean? 

Stretching paper is a process that will stop your watercolour paper from buckling. Stretching works best if you’re wanting large washes and using a thinner paper (under 300gsm). To see how to stretch watercolour paper, you can check out our handy how-to. 

To stretch paper, use gummed tape (masking and sticky tape won’t stick to wet paper as well, so gummed tape works best for this), immerse your paper in cold water for a few minutes, (this can be anywhere from 2 minutes to 10 minutes), then hold the paper up by one corner and give it a little shake to remove excess water. Then place the paper onto a board and smooth it out from the centre, a dry sponge will also help remove any excess water and flatten the paper for taping. Then tape the paper and leave it to dry.

The water will expand the fibres and the drying contracts them, which is why you need to submerge the paper and then wait for the paper to dry. Once dry, it’ll shrink back and then you’re ready to go. 

10. What is the difference between hot press and cold press watercolour paper?

Hot pressed watercolour paper has a smooth surface and cold pressed paper has a semi-rough surface. Hot pressed paper can be tricky to work with but it’s great for precise work that needs smooth surface. Cold pressed paper has bit more “grit,” which is great for smooth washes, and it has an extra bit of texture for the paint to grip to. The Mont Marte watercolour paper range has a medium tooth and is considered a cold pressed paper, so it’s versatile for a range of techniques.

Hand fixing buckled watercolour paper by placing a damp piece of paper over the top.

11. Can you tell me how to fix warped watercolour paper?

It can be annoying to see your watercolour paper buckle or warp. But luckily there's a quick fix. Check out how to fix warped watercolour paper here.


Do you have any more watercolour woes? From brushes to pans and tubes, you can check out our commonly asked watercolour questions here. Or for more on our pads and papers, check out our guide to sketch books and papers.

We hope that solved your questions around watercolour papers. If you’ve got any more creative questions, send them through on our socials, (Instagram or Facebook) we’re always happy to help.