Watercolor 101 – Stretching Watercolor Paper

Stop me if you’ve heard this one before:  “Help, my watercolor paper isn’t laying flat – it’s all warped in the matt!”  or “Darnit, my watercolor piece tore and I had to start over!” or even worse:  “Hey look, I tried watercolor and it wasn’t for me – the more water and paint I added, the worse things got.”

I have been there, done that. I have painted on unstretched paper, carefully trying not to get too much watercolor volume on the paper, fearing it would buckle. I have purchased those really expensive watercolor pads with glue on all four edges…and then still haven’t been happy with the result.  I have taken watercolor classes with instructors that told me I had to tape watercolor edges down tightly to my drawing board using a special tape.  I have also been told you had to get a special wooden board with routed grooves along all four edges so that waxed twine could be pressed down into them in order to properly hold the sopping wet paper.  (Yes, I know this is ridiculous….oh, how I have suffered!)

And so to clear the air, once and for all, THIS is how to stretch watercolor paper.  This is what I teach my students first in my “Intro to Watercolor” workshop.


  1. First get some Gatorboard. (This is not an advertisement for Gatorboard – in theory any flat porous surface that will not bend but will accept stapling will work.  Got any ideas for substitutes?  Please comment!)  Gatorboard is available at University Art as well as online at Dick Blick and Amazon.  Be sure you buy Gatorboard in the size that approximates the size you like to work in…I like a half sheet of watercolor paper so that’s the size I get.  You can always cut your board in half (with careful measuring, and a box cutter/exacto blade) if you decide it’s too big – but that can be a hassle.  Measure one of your existing paintings and aim for that size.  The best part is you can use the same board over and over again.  I have boards that are 20 years old…

Soak your paper

  1. Once you’ve gotten your paper and your correctly sized Gatorboard ready, fill a large tray or bathtub with water. It does not need to be hot.  The paper should lie down flat in the shallow water.  Leave it there for 10 minutes.  You can see little spots begin to form as the water starts to dissolve the paper…don’t let the spots take over! Take it out!  Don’t leave it in there and walk away to do something else.  Paper can become mush if you let it sit too long.  You may wonder, what’s happening?  Why am I doing this?  Watercolor paper has something in it called “sizing” that strengthens and protects the paper fibers.  When you wet the sizing and dissolve it, you loosen the paper structure a little bit.   This is why your paper warps if you get one part of it really wet.  Releasing the sizing all over your paper evenly beforehand ensures no buckling or warping, no matter how wet your paper gets.

I’m going to say right here that you need to be using real watercolor paper for watercolorists, or none of this will work.  It needs to be at least 140 lb. weight and be sturdy enough to take a soaking.  Cheap, student brands that come in 8 ½ x 11 inch pads are not what you want.  Get the thickest, heaviest, sturdiest watercolor paper you can afford.  Some brands include Arches, Fabriano, Kilimanjaro, Sennelier.  I am not going to judge if you buy Strathmore because that is all you can find, try it anyway, but be careful not to soak it too long.  I find that the better papers yield a better result, and the cheaper papers just “fuzz up” and decay, they don’t take the kind of beating I like to give them.

Staple around the edges

Watercolor 101 by Leah Jay

Watercolor 101 by Leah Jay

  1. Let your paper drip into the tub or tray so you can get it to the Gatorboard without dripping water on your shoes! Lay it flat and even on the surface of the board.  To affix it around the edges, use an ordinary office stapler, opened so the two parts lay flat.  Now, while the paper is still soaking wet, staple the paper around the perimeter. Make your staples regularly spaced with no more than an inch between staples.  Let it dry overnight.  Paint away!

After you’ve created your masterpiece, before removing it from the board, THAT’s the time to use a protective spray on the work. (I can’t tell you how many times I’ve forgotten that I needed to spray the finished work until it had come off the board…..oops!)  You can always spray it afterward but it may warp a little tiny bit depending on how much spray you’re using…and the point was to keep that paper 100% flat, right?  It’s also easy to spray it evenly across the surface while it’s still attached to the board, so it’s best to do this first.  Let that dry (outside or with great ventilation) before removing it.

Some people have trouble with taking out staples.  I think there are two ways, one is to lift the dry paper starting at one corner and simply – lift the staples right along with it.  It will make a disturbing ripping sound, but if your watercolor paper is good and sturdy, this way is quick.  Some staples might fall to the floor, and some might cling to the paper, so it’s not the tidiest method, but it works for me.  The second way is to carefully pry out each staple with a small flat head screwdriver.  It’s slower, but neater, and far less risky it will preserve the precious work you’ve done no matter what.  It’s up to you.

By stretching your watercolor paper right, the possibilities are endless!  You can create washes that cover your paper completely, drip color ALL OVER your paper, use sponges and credit cards to push the watercolor around, use plastic wrap and bubble wrap to create textures, whatever you like.  As long as you let your creation dry completely before removing it from the board, it will dry flat.  Pretty cool.  Now you can enjoy watercolor as a medium – with all of the amazing drippy, runny characteristics that make it so much fun!

Watercolor 101 by Leah Jay

To learn more great techniques and processes from Leah check out her Fundamentals of Art series.

© 2018 Leah Jay | leahjayart.com

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Leah JLeah Jay (Jakusovszky) has been an artist and illustrator in San Jose for 25 years. She creates using a variety of media including watercolor, acrylic, pastel, ink, and collage. Her illustrative work has been featured in many books, and highlights from her career include directing 2001’s WTC Memorial Art Project to facilitate artist’s responses to 9/11 and successfully crowdfunding her artbook “Amphibian Love” to benefit Save the Frogs in 2015.


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2 years ago

This is the technique that works! For watercolor classes in college I got a cheap door from Home Depot and had them cut it to the size I needed. I added a heavy-duty metal handle to the side for carrying it to/from class, and voila! I still have and use my half-a-door for painting full sheets of watercolor.