Watercolor Paper Weights / To Stretch Or Not To Stretch

I'm trying to teach some of my friends about painting in watercolor.  And since I've yet to finish the small projects I'm working on and can't post new finished painting pictures yet, I thought I'd use the time to share some knowledge instead.  I recently got asked about stretching watercolor paper so here goes.  

We will focus on paper weight first, as it will have the most significance with the process of stretching watercolor paper.  

Watercolor paper comes in various weights, sizes and types.  Because many of the other options such as yupo and boards are still not readily available in my country, we will concentrate first on what is, which is paper.  Common paper weights for watercolor paper are: 190 gsm (also known as 90lb), 300 gsm (140 lb) and 638 gsm (300 lb).  A most common mistake is to interchange 140lb with 300lb because both use 300 values but with different units.  This has caused many to wonder why their watercolor paper is buckling despite being 300 of something.  

190 gsm is the lightest or thinnest of the three.  It can tolerate the least amount of water when you paint.  That means your paper will have a tendency to get out of shape or warp when you wet it with water.  It can take dry brush but warps with watercolor washes.  The pros and the cons:  90 lb paper is cheaper, takes less paint to achieve color brilliance, and is easier to roll into canisters for shipping or posting unframed but it is also easier to damage, takes less abuse when you're the type who likes to rework areas, requires frequent drying time in between applications (the waiting can be a hassle and disrupts your momentum) and you definitely need to stretch it.  Stretching ensures that, though there may be buckling while you are painting, the paper will revert back to its flat or stretched state when it dries.  When you stretch 190 gsm (90lb) paper, you have to work fast.  After wetting the paper and laying it down on the board for stapling (especially true for large format paintings), if you do not work fast enough, you  might find yourself  trying to staple down an already warped or misshapen paper.  

300 gsm or 140 lb paper is the "just right" paper, at least for me it is.  Not too thin that it can't take water abuse and not too thick that it is hard to roll up for transport.  You may stretch or not stretch depending on your style of painting.  If you paint mostly dry brush or using only little water, you may forgo the stretching and securing part.  But if you like using washes, you will need to stretch it on a board to prevent buckling.  Again, stretching and stapling the paper on a sturdy support makes it possible for the paper to get back to its formerly flat state as the paper dries.  I'm not sure if others have experienced the same thing but I notice that since converting to 140 lb paper, I have been using more paint.  To get the same color intensity that I used to get so easily with 90lb, I needed to apply more layers or paint.  Maybe it is just my imagination or maybe it may also have something to do with the paper being thicker and paint pigments getting pulled deeper into the fibers thereby appearing to lighten as the paper dries.  To counter, I add additional layers of color on top of previous applications until I get the brightness that I want.  This capillary action or pulling of paint deeper into the paper may actually be a good thing because paintings I did on 140lb paper, done more than 15 years ago, seem to be standing the test of time well.  

300 lb or 638 gsm paper is the thickest I've tried so far.  Reminds me of the local cardboard we have because of its thickness and rigidity.  I remember being afraid to roll a finished painting I did on a 300 lb paper because I somehow was getting this feeling that the paper would get mini cracks if I force it into a tighter roll that would fit it in a canister.   I ended up shipping the painting flat and inside a heavy wood container to protect it when I sent it overseas.  It added a lot to the freight cost.  Of course, that's just my paranoia and maybe the paper could have stood the rolling abuse.  Anyway, its disadvantage is also an advantage because being so rigid means that it is structurally more able to stand water loading.  Even with no stretching and stapling on board, you can work on 300 lb paper with multiple washes without fear that the paper will buckle.  Within, reason, of course.  If your style is to immerse the paper under colored water for minutes at a time, even the hardiest of paper may give.  I have to say this because most beginners like to experiment and I just might find myself being challenged on my claim.  haha.  

The choice of paper weight is personal for every artist.  There are no rules that says you are to use only this kind of paper, this brand, this style.  But I find that any tool would serve you best when you know how to use it.  So take time to learn all you can about the materials you will be encountering and using for your craft.  This lessens potential problems while you paint and makes your painting experience more enjoyable.


Addendum:
You might miss this in the comment box so I added Stan's comment as an addendum on the article itself.
Hi Karen.  There is a 200 lb cold press paper produced by Saunders Waterford.  I have used it for years.  Easy to work with and does not need stretching.  Not as expensive as 300lb but more durable than 140lb.

Here is also an additional advice for watercolor painters who like to paint very wet.  I asked Laura's permission to repost here her comment on my page in facebook.
I work on both stretched and unstretched papers.  It all depends on how wet I'm going to work.  With my florals I usually do a lot of wet-in-wet and many glazes so will stretch even 300# paper... unless I do a float mount.  Those staple holes really ruin a deckled edge!


Thank you Stan. Thank you Laura.

Stan Hughes does not have a website but his art may be viewed on facebook.  He also showcases there the work of Jan, his wife who is also an artist.
Stan Hughes on facebook.
Stan is also the author of several blogs on painting and other interests.   I'm particularly impressed at how he is keeping alive the tradition of drum making.   Stan's Art (the new style) , Stan's Art (Dreams and Things) , Stan's Drums.

Laura Dicus' art may be seen on her website http://www.laura-art.com/  She also has a facebook page where you can view her paintings and WIPS (works in progress).  Laura Dicus, Artist (page).


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