Does Paint Go Bad? Different Paint Types and Their Expiration
If you’re a homeowner, a DIY’er, or even an artist, you may have one or two stray cans of paint that have been sitting in a corner somewhere waiting to be used. If you’re not sure about how usable that leftover can of paint is, we’ve got you covered. As professionals who’ve worked with an array of paints, we’re here to guide you through everything you need to know on the shelf life of paint.
So if you’re interested in finding out if that can of paint you have leftover is still salvageable: keep reading!
How long does it take before latex paint goes bad?
The shelf life of your paint is heavily dependent on three factors: the type of paint, how it was stored, as well as if the seal to the paint container has been broken. When it comes to latex paint, the shelf life of an unopened container can last you for about ten years, with no issues. Once the can has been opened, however, the shelf life begins to drop down significantly – lasting only around three years.
How long does it take before oil-based paint goes bad?
Out of the options available for your painting needs, oil paint reigns supreme when reviewing the average shelf life. To give perspective, some specialty oil paints can last up to 30 years depending on the ingredients of the paint and whether or not it was exposed to extreme temperatures. Outside of the unique, long lasting products, the average oil paint can easily withstand ten to fifteen years on the shelf if it remains unopened. Once opened, the shelf life drops down to around eight to ten years depending on the environment.
Unfortunately, there is no definitive answer on how long the shelf life of paint should be, unopened or not. Looking for signs of bacteria and degradation of quality will be your only tale-tell.
Does paint primer have an expiration date?
So – if paint has a shelf life, what about primer? Surely there must be a similarity in the length of time primer stays viable, right?
Unfortunately the quality of primer degrades at a considerably faster rate than that of your standard paint once opened, but if left unopened the product should last for around 10 years. Once opened, you may get around two years out of your primer purchase.
While the average shelf life may be estimated to be anywhere between two to ten years, it is important to inspect your primer and test it before using it on any other projects. Since the main purpose of using a primer is to prolong the life and quality of your paint, it is critical to ensure that the product is still viable by looking for signs of degradation.
Signs that your paint shouldn’t be used
Since the window of viability for paint is so vast and dependent on multiple variables, it is important to visually assess your paint before using it. A few simple tests can help you determine if the paint is still usable or if bacteria have taken their toll.
The smell
When paint goes bad, it is usually because bacteria is allowed to grow within the can and eat away at the binding agents in the paint. As the mold grows, it releases a waste product in the form of gas that fills the paint can. Over time this gas can cause the can to bulge or even give off a putrid odor. If you notice that your paint smells funny, if not rotten, save yourself the time and money by disposing of it and getting a new product.
Changes in consistency of the paint
Fresh out of the can, paint has a smooth, silky consistency. If that consistency were to change, you may be dealing with expired products. For example, if the paint has become lumpy and curdled, this is an immediate indicator that the entire can is no longer viable. If the consistency has changed to anything more than just separating, then it is best to dispose of the can and purchase a replacement.
Your paint has separated and won’t re-mix
Like natural peanut butter, paint can begin to separate over time creating two very different layers of liquid. While separation can be a normal development over time, the indicator that there is an issue is if the paint will not re-mix. In situations where separation has occurred, simply mix the product and wait for a minimum of fifteen minutes. If the paint returns to its separated state, it is no longer usable.
Please note that there may be situations where a thin layer of dried paint may appear on the top of your can, this should not be mixed in and does not mean your paint has spoiled. Simply remove the layer and check for the other indicators.
The best way to get rid of expired paint
If your paint has expired and you need to dispose of it, you can't just toss it in the trash. Latex paint disposal is as easy as mixing it with cat litter and waiting for it to solidify. Oil based paint, however, is considered toxic and must be dropped off at an approved disposal area. Check with your local waste management for more information.
Avoid leftover paint by hiring a professional painting company!
Getting stuck with having to store leftover paint can become a hassle. Avoid the hassle and enjoy peace of mind by hiring a professional. Here at Old Crow Painting, there is no project too big or too small. Call for your free consultation today!