When painting your home or projects with latex paint you are likely to have extra paint. Because quality paint can be somewhat of an investment today it is important to store leftover paint in a way that it will last until it is needed.
No matter what you do to protect your investment you should remember that latex paint does have a shelf life. Most manufacturers will suggest that both oil and latex paint be used within 2 years of manufacture if it is in its original sealed container. In many instances you may find that this time can be extended up to 5 years with proper care.
Storage Containers
Latex paint comes in standard sized containers from 5 gallons down to a half pint. Most 5 gallon containers are plastic and 1 gallon containers are metal however you may find containers of either material used throughout the size range.
Metal paint cans should be sealed or lined with an enamel paint that will protect your paint from reacting with the metal or possibly rust in later dates.
When storing paint in any container it is important that the lid seals air tight and that the product fills the container to the top. By reducing the amount of air in the can or the ability for the can to breath you will reduce the evaporation of the water and solvents that make the paint liquid. This is probably the biggest problem you will have when storing paint.
Always clean the rim and inside of the lid area where it seals before you return your can or container for long term storage.
This is especially important for containers with screw on lids.
If possible store the paint in its original container but if more then 25% of the can is filled with air you should store the paint in a similar type but smaller container that will allow you to fill the can to the top.
Although not always the best idea you can also store paint in glass jars that food came in. If you do this you must make sure that the lid has a good seal and that the paint can be stored in a location where it will not be damaged or broken.
Glass containers allow you to see the product and make quick selections but if you are storing the paint in metal or opaque plastic container put a small dab of the paint on the lid or side of the can that will let you pick it out quickly.
Temperatures
It is important to store your paint at room temperature… now that can be misleading because whatever temperature a room is … will be room temperature but you want to store the paint as close to 70F as you can. Paint can be stored at lower and higher temperatures from 40F to 90F but it should never be allowed to freeze or remain hot for long periods of time.
Fluctuation in temperature can also cause condensation.
Keeping the paint mixed
Although latex paint will separate overtime and although mixing or shaking can restore its quality it is important to make sure the paint is not allowed to sit unmixed for extended periods of time.
So, when you are working around your paint especially smaller cans that may have a larger proportion of air in them that you shake the paint to remix and products that may have separated.
Final Note
Protecting your paint investment is important and this is one reason that you should always keep a few empty and cleaned containers from used paint. You can store the empty containers inside each other to reduce space and collecting a few different sizes is a great idea.
If you do not have good quality containers you can purchase them from your paint supplier.