How Long Does Paint Last?
If you own a home there’s a good chance you have a gallon of paint kicking around somewhere for touch ups or because it was half-full. Obviously, to save a dollar or to be a good steward of your resources, you’re likely to want to use the leftover paint rather than waste it but is that a good idea? How long paint lasts really depends on several factors.
Types of interior paint
Before we dive into their shelf-life, let’s first go over the common types of paints used in and on homes in the Greater Birmingham metro area. For this conversation, we’re not talking about matte, semi-gloss, satin, or really any type of paint finish but rather what the paint is made of.
Latex paint
Latex paint is a water-based paint that is made from acrylic resin. It is easier to apply than acrylic paint, dries faster, is cheaper in comparison to acrylic, emits less fumes, and easier to clean up. Last of all, latex paint typically covers walls with fewer coats than its contemporaries.
Acrylic paint
Acrylic paint is a chemical-based paint made from pigment suspended in acrylic polymer solution and acrylic resin. It tends to contract and expand with varying temperatures which means it may hold better than latex paint. Cleaning up after painting with acrylics takes more work and this type of paint will produce more odors and fumes than latex. Acrylic paint is a good option for exterior painting because it is more resistant to fading and damaging UV rays.
Oil-based paint
As the name suggests, this type of paint uses natural or synthetic oil as its base. It is a very durable paint that is more resistant to lower temperatures, is easy to apply and provides great coverage. In fact, oil-based paints do a great job of covering small mars and other minimal imperfections and can be applied directly over stained or dirty surfaces. The downside to oil-based paint is that it gives off a strong odor, is more likely to fade or discolor, doesn’t hold up well against peeling or mildew, and will typically leave noticeable marks over areas you attempt to touch up.
Chalk paint
Chalk paint is a decorative paint that creates a chalky appearance to surfaces it covers. It is NOT chalkboard paint that you can write on. This type of water-based paint is often used to give a vintage or distressed look. It can be applied to clean, dry surfaces and over ones already painted. It is also easy to clean up. While it can be used to cover whole interior walls, it is more often used on furniture.
Shelf-life of paint
Below you’ll find a list of the paints we just discussed along with the estimated shelf-life for each. It is important to note that time can be affected by the way the paint is stored.
Latex paint – Up to 2 years unopened
Acrylic paint – Up to 10 years unopened
Oil-based paint – Up to 2 year unopened
Chalk paint – 1 year with the potential for more, unopened
Signs that paint has gone bad
Rancid or sour-smelling paint
If you open a can of previously used paint and notice a smell that is less than appealing, it is likely your paint has bacterial growth and has gone bad. Rancid, foul, sour, and moldy or mildewed are common adjectives used to describe paint that is no longer viable.
Paint has been frozen and thawed repeatedly
Paint that has been frozen and then thawed multiple times will eventually break down – it’s inevitable. While paint manufacturer, Glidden, states that frozen paint can be successfully thawed and used as long as it’s not clumpy and does not smell bad (see previous point), we encourage homeowners to be wary of paint that has gone through the cycle numerous times.
Overly lumpy paint
Piggybacking on the previous sign, overly lumpy paint is a clear indication that it’s time to toss the can. It is natural for latex paint to develop a film but when that film turns into solidified chunks, there’s no going back.
Jelly-like paint
When paint reaches the point where it cannot be classified as either solid or liquid, it’s past its prime. Throw away any paint that is goopy and that refuses to mix smoothly.
How to preserve paint for a long shelf life
Buying paint can be expensive. Make the most of the paint you purchase by storing it with an eye towards preservation. Here’s what we suggest:
Store paint in a cool, dry place.
Do not let paint freeze.
Avoid temperature spikes in either direction.
Remove all impurities as well as leaves, grass, and other organic matter that may have fallen in the can.
Clean the rim of the paint can, place a layer of plastic between the can and lid, and make sure the lid fits tightly without denting (a rubber mallet is a great tool for this particular job).
Experienced painters serving Greater Birmingham
Serve One Construction, a locally owned and family-operated construction and handyman company offers professional painting services for homes and businesses in Mountain Brook, Vestavia Hills, and throughout the Greater Birmingham metro area. Specializing in interior and exterior paint projects, our team of pros are ready to help you tackle all your paint jobs. Contact us today to schedule an on-site consultation!