We are commonly asked something like - I want to store some paint in my garage, how long will the product last?
The shelf life for all FLAG paint products can be decades, as long as you follow some guidelines:
Don't open a product unless you need to (keep the air out of new products), and where possible, keep the original seal for as long as possible.
If you have a part used can, it's advisable to put a small amount of water or solvent (depending on the nature/type of product) on top of the paint before replacing the lid, this will help counteract the effects of the extra air inside the can. Get the lid back on as tightly as possible, you may need to clean away some dried up paint from the edges and the lid to ensure a good air-tight seal.
Store paint cans away from frost and avoid conditions that would result in the can rusting (especially for water based paints). Always ensure that the lid is put back on as tightly as possible. If a paint can is beginning to rust, we recommend decanting the product into a new rust free and suitable air tight container.
If the paint is water-based, then you will have to determine whether it's been subjected to below freezing temperatures, freezing normally destroys water-based paints and makes them unusable. It's also important to avoid high temperatures and extreme temperate changes to allow paints to remain stable.
Open up any old cans carefully. Remove any dry residue from the top and try to keep any dried bits out of the paint. If there's thin liquid resting on the top, this will need to be fully mixed back in to the product before use. Stir the paint by lifting the paint up from the bottom of the can while stirring. Just shaking an old can is often not good enough! The paint should be homogeneous (all the same state - nice and smooth consistency).
Turning an old can upside down (after first ensuring that the lid is on correctly) a few days before you need to use it, can help the mixing process by getting some of the heavy ingredients to move back away from the bottom of the can.