Quick Answer
Paint that is 5 years old may still be usable if it was properly stored in a cool, dry place with the lid sealed tightly. However, old paint is more likely to have issues like skinning, separation, lumps, and changes in consistency or color. Test a small amount first before committing to using older paint for a full project.
What Happens to Old Paint Over Time
Over time, paint can undergo changes that may make it less usable or desirable:
- Skinning – The surface may dry and form a skin, which needs to be filtered out before use.
- Separation – The pigment and carrier oil may separate, requiring thorough stirring to recombine.
- Thickening – Evaporation causes the paint to thicken in the can.
- Lumps – Pigment and binders may clump together.
- Color changes – Pigments may fade or alter over time.
The older the paint, the more likely it is to have issues. Paint 5 years old has a higher chance of degradation compared to paint used within 1-2 years. Proper storage helps maintain quality for longer.
How to Store Paint Properly
For the best longevity, paint should be stored:
- In a cool, dry place – between 50-70°F is ideal.
- Out of direct sunlight, which can degrade pigments.
- With the lid sealed tightly to prevent air exposure.
- Upright, to keep the lid sealed with the liquid and prevent leaks.
Avoid freezing, excessive heat, dampness, or water exposure when storing paint. Try to use paint within 1-2 years for best results.
Signs the Paint May Be Unusable
Before cracking open that old can of paint, check for the following issues:
- The paint is lumpy or clumpy when stirred.
- The color or sheen seems off compared to what you remember.
- An oil slick or separation is present on the surface.
- The paint has a rancid odor.
- Mold or skin has formed on the surface.
- The can is rusted or deteriorated.
- The consistency is excessively thick or gummy.
If you observe any of these issues, it’s best to dispose of the paint instead of trying to salvage it. Rancid or moldy paint can make you sick.
How to Test Old Paint Before Use
If the paint looks usable upon inspection, conduct a small test to check quality before committing to using it for your full project:
- Thoroughly mix the paint by stirring with a paint stick.
- Pour a small amount into a disposable container.
- Check consistency – it should flow easily off a paint stick.
- Brush a small swatch onto cardboard or scrap wood.
- Allow to dry completely (at least 24 hours).
- Inspect coverage, texture, sheen and color once dry.
- Compare to a fresh sample of the same paint if possible.
If the tested paint dries with poor coverage, uneven texture, dull finish or color variance from a fresh sample, it’s best to discard and purchase new paint.
How to Improve Quality of Old Paint
If your test shows acceptable results, you may be able to extend the life of older paint and improve quality using these methods:
- Stir thoroughly – Mix up pigment that may have settled on the bottom of the can.
- Strain – Pour through cheesecloth or a paint filter to remove lumps or skin.
- Add thinner – Sparingly thin with the proper thinner to improve workability.
- Boxing – Mix together batches of old paint for color consistency.
Avoid over-thinning, which can reduce hide and longevity. Test strained or thinned paint before full application.
When to Toss Old Paint
It’s best to dispose of paint if:
- You didn’t store it properly, allowing freezing, heat exposure, or opening.
- The can is damaged, rusted or leaking.
- You observe signs of skinning, clumps, separation, or mold.
- The color, sheen or texture seems severely compromised.
Safely dispose of old latex paint by allowing it to dry out completely before placing the can in the regular trash. Dispose of oil-based paints at hazardous waste collection sites.
When in doubt, it’s usually best to start fresh with new paint rather than risk having a peeling, low-coverage mess to clean up later if old paint fails.
Frequently Asked Questions
Does paint expire?
Paint does not have a definite shelf life or expiration date. Over time, degradation in quality is likely to occur. Many paints become unusable after 5-10 years due to chemical changes. Always test older paint before relying on it for a major project.
Can old latex paint be reused?
Latex paint over 5 years old is not recommended for reuse, but may be salvageable if properly stored. Test a sample first. Thinning, straining, and thorough mixing can temporarily improve workability. Discard paint if severely deteriorated.
What are signs paint has gone bad?
Thickening, skinning, separation, odor, color/sheen change, mold, and lumpiness are signs paint may be unusable. The paint can may also show rust, bulging or leaks if paint has gone bad. Always do a test patch on cardboard before using old paint.
Can I mix new and old paint?
It’s not recommended. Chemical differences between fresh and old paint can cause issues with adhesion, sheen uniformity, and touch-up visibility. However, “boxing” small amounts of similar old paints can help ensure color consistency.
How long does oil-based paint last unopened?
Properly stored oil paint can potentially last up to 15 years unopened, compared to 2-5 years once opened. Always inspect and test old oil paint before applying to ensure it has not deteriorated. Proper storage extends shelf life.
What happens if you freeze paint?
Freezing paint can permanently damage it by causing the water and pigments/solids to separate. The chemistry is thrown off balance. Thawed paint often becomes lumpy or stringy and unusable. Never let paint freeze while in storage.
Key Takeaways
- Test older paint before use – check for skinning, odor, texture, and color changes.
- Stir, strain, and thin paint as needed to improve workability.
- Dispose of paint that is lumpy, moldy, separated, or severely degraded.
- Proper storage extends the shelf life – keep paint cool, dry, sealed, and upright.
- When in doubt, purchase fresh paint rather than struggle with older product of questionable quality.
Conclusion
While paint does not truly expire, its quality tends to deteriorate over the course of 5-10 years. Paint stored longer than 2-3 years should be inspected and tested before being used for important painting projects. Look for signs of skinning, clumps, separation, color shift, and thickness or gumminess. With proper storage and some straining or thinning, older paint may be revived for limited use. However, it’s often wisest to discard severely degraded paint and start fresh with new product for the best results. Take steps to use paint within 1-2 years whenever possible, and store it properly sealed and in temperature-stable conditions. With a quality top-coat paint and proper application, you’ll achieve a long-lasting paint job you don’t have to redo year after year.