Paint can be expensive and the majority of the time, you are left with plenty in the tin, which means disposing of it can be wasteful. However, if you can store it appropriately, you can keep it to reuse at a later date or for touch-ups.
To ensure that any old paint you have doesn’t go to waste, below is everything you need to know regarding how long paint lasts and the correct way of storing it.
Does Paint Go Off?
Paint will eventually expire and become unusable but how it’s stored will determine how long it can last. As well as how it’s stored, other factors that determine the shelf life of paint include whether the tin has been opened, its type and the quality of the paint. However, the length of time before the paint goes off is much longer than most people think.
If you’ve had paint in storage and wondering if it has gone off, below are some of the signs to look out for:
- Terrible smell
- Lumpy and thick texture
- Separation (discussed in this article)
- Mould growth
- Change in colour
The main telltale sign that paint is off is a foul or rancid smell and if you try to use this paint, the smell will remain on your walls and ceilings too. Therefore, simply dispose of the paint and don’t take the risk.
Oil vs Water-Based Paint Expiry
The type of paint that you wish to store will also affect how long it can last before it goes bad. Although all paint will eventually go bad, water-based paints have a longer shelf-life when compared to oil-based paint (as well as other types of paints). This is mainly due to a water-based paint’s chemical composition, faster-drying process through evaporation and lower levels of volatile organic compounds (VOCs).
How Long Does Paint Last Once Opened?
From our experience, water-based paint that has been opened will usually last up to 5 years whereas oil-based paints have a shorter lifespan of between 2 to 3 years.
However, it’s important to note that you will only achieve this lifespan if the paint is correctly stored (as discussed below). If you store old paint incorrectly, you will be lucky for it to last even a few months.
How Long Does Unopened Paint Last?
If you are yet to open the paint, water-based paints can last up to 10 years whereas oil-based paints can last up to 5 years. If unopened, most brands will state on the tin (either on the lid or bottom) the date of expiry.
How To Store Paint
If you want to ensure your paint doesn’t go off, you must store it correctly and below are some of our top tips:
- Seal The Lid Properly: After each use, ensure the paint lid is sealed tightly to prevent air from entering.
- Choose The Right Storage Location: Store paint in a cool, dry and well-ventilated area and avoid places with extreme temperatures or humidity such as garages, sheds or basements.
- Keep Paint Away From Direct Sunlight: Exposure to sunlight can degrade the paint’s quality and affect its colour over time.
- Prevent Freezing: In the winter months, water-based paints can freeze and become unusable. Therefore, avoid storing paint in areas prone to freezing and if necessary, bring the paint indoors during cold spells (if stored outside).
- Avoid Extreme Temperatures: Extreme heat can also negatively impact paint quality and you should avoid storing paint in places prone to excessive heat such as near radiators or heating appliances.
- Label The Paint Can: Clearly label the paint can with essential information such as the colour name, paint type and the date of purchase or last use. This makes it easier to identify the paint and its age, helping you prioritize which paint to use first.
If you have bought some high-quality paint brushes and want to be able to reuse them, they can also be stored with your tins of paint. However, before storing them, you’ll want to ensure they are thoroughly cleaned with excess paint removed from the bristles. You will also want to reshape the bristles to their original form if they are distorted in shape. Once cleaned, store them in an upright position by hanging them on a hook or in a dedicated paint brush holder.
With regards to paint rollers, we would advise that you keep the roller but replace the sleeve after each use. This is because the main expense of a roller is the handle and sleeve holder and the sleeves are cheap to buy.
Has The Paint Separated?
Paint can begin to separate when the different components of the paint such as pigments, binders and solvents gradually start to separate and form distinct layers over time.
However, if you have opened an old paint tin to find that the paint has separated, it doesn’t always mean that the paint is off. This is because it can still be used if it returns back to its original consistency.
How To Rescue Separated Paint?
If the paint has been stored correctly and it doesn’t smell, there may be a chance that you can rescue the paint.
In the photos below, we rescued an emulsion paint that had separated and we did this by simply giving it a good stir until it returned to the original consistency. We then used it for touch-ups and the colour match was the same as when it was first used.
It’s important to note that if you attempt to use separated paint without properly remixing it, you might experience problems such as uneven colour, streaks, poor coverage and adhesion issues.
How To Dispose of Old Paint
If you are anything like the team at DIY Works, you probably go through a lot of paint and you may need to dispose of old paint quite regularly. As you can probably imagine, you shouldn’t simply pour it down the sink. Instead, you should dispose of old paint at your local waste recycling centre where most have a dedicated section for paint.
However, before disposing of the paint, you may want to consider keeping it for any touch-ups. For example, if you have half a tin of gloss paint, it can be very handy to have some leftover for tidying up scruffs, scrapes and defects in the paint. Alternatively, you may want to consider donating it on a Facebook group or neighbourhood-based community portal.
Reusing old paint is a great way to save money and perform touch-ups without having to buy new paint. However, to make the most of old paint, you must store it correctly and avoid using it if it has gone bad.
As a general rule, you should expect most oil and water-based paints to last a few years but if you are using other paints such as chalk paint, it may only last one year at best.
Hopefully our guide on how long paint lasts has answered all your questions but if not, feel free to get in touch and we will try to provide our assistance where possible.