GSM is an acronym for “Grams Per Square Metre’ which means how much a single sheet of paper measuring 1m x 1m weighs. The lower the GSM the lighter the paper and the higher the GSM the heavier the paper. … 70gsm to 80gsm. This range of paper weight is commonly used as office paper and is normally used as copier paper. Heavier weight cartridge papers like the Snowdon Cartridge 300gsm can cope with stronger mark-making when drawing painting or washes of ink. The heavier weight papers can be used with acrylic paint, and I personally would not recommend using anything less than 300 gsm as any lower gsm could result in the paper buckling, tearing or collapsing.

The great advantage of using the heavier duty papers for acrylic painting means don’t have to stretch the paper before applying the paint. You can begin painting on them without any preparation because they’re extra thick and contain enough sizing to prevent the paper from buckling. The thinner student grade papers may buckle if you paint on them with acrylics. Mix Media Paper of a high gsm incorporates professional characteristics at a value price. Its heavy sizing, makes it ideal for watercolour and acrylics, as well as dry media. In the hydrangea painting I used a textured medium on the background which I let dry before applying the paint and the 300gsm paper held up excellently.