Painting a house is a hard task. Then, it is complex to define how much paint you will need. Painting a house is an extensive task, yet it is complex to define how much paint you will need to cover the area you want to paint.
Sometimes, you end up buying an extra paint can, but you don’t use the whole product, and you probably have thought about saving it for the future. Thus, you may be wondering how long the paint lasts once it is opened.
Latex and water-based paint can last over 10 – 15 years when they haven’t been opened; however, once you have opened a can, the life span can reduce to 8 from 10 years according to the way you have stored the paint can. The paint can last more than what is written on the expiration date.
Paint is a pigment made of diverse polymers according to the paint type. For interior and exterior painting, people used liquid water-based or oil-based paint.
Furthermore, people don’t use the whole paint can and save it for later; but the paint will last more or less time according to the paint type, and the curation process will be affected.
What Happens If You Use Old Paint?
Contents
Nothing will happen if you use old paint if this has been stored correctly. Yet, oil-based paints can be harmful to you if they are reused after a long time. Moreover, any old paint type may cure slower, and even mold can grow once you have applied the paint.
It is not recommended to use old oil-based paints or alkyd when they are stored for a long time. They use solvents and pigments that can turn toxic after a few years.
Moreover, they can become hazardous if you don’t store the paint correctly. However, it is another story for water-based paint and latex one. If you store them properly, these paint types can last for years and be used after a long time.
Any paint type contains volatile organic compounds like toluene or acetone. After years of being stored, those VOCs can generate fumes; though, they can cause skin irritation, nausea, and headaches. Moreover, old houses (built before 1978) used lead-based paint; this paint contains toxic metals that can be dangerous after so many years.
Paints have four main components: the binder, diluent, pigment, and additives. The binder is made of natural or syntactic components (polymers) that help with film formation.
In general terms, the binder helps to dry the diluent and leaves a consistent film once the paint has cured. The diluent is that component that dissolves the pigment and polymers. Then, the diluent can be thinner or a solvent. However, some paints may not include any diluent.
Next, it is the pigments that can be natural or synthetic. Pigments can be toxic, yet water-based and latex pigments are safe. Water-based and latex paints are most recommendable for house painting. Besides, they can be removed easily and do not leave toxic compounds in the environment.
However, most of those toxic pigments are not used anymore. Yet, some pigments and dyes can be toxic after years, and it is not recommended to use them if they are out of date or were stored for too long.
How Can You Tell If Paint Is Bad?

Everyone has saved the remainder of the paint to use later, yet the paint is stored for years in the garage’s corner. Then, you may want to remodel a room and remember that old paint that you stored a few years ago. So, you should be wondering if that old paint is still usable.
You can say an old paint is bad when it smells moldy, has dried, or is chunky. Paint cans have a lifespan of 5 years to even 15 when these haven’t been opened, so according to how good you store the can, the life span can be reduced to even half.
One of the first things to check when you open an old paint can is the smell. A paint commonly expels fumes; the smell is regularly soft and doesn’t cause any harm when it is a new paint can, but the old paint tends to have strong fumes that irritate skin and throat. Then, if the smell is strong and damp, the paint probably has mold or can grow mold wherever you apply it.
So, if the paint has a normal smell but has separated or has a dry layer on it, not everything is lost. According to the paint type, it is normal that the component separates after a long time. Besides, water-based or latex paint tends to dry, creating a thin layer, yet the paint remains usable.
How Long Does Paint Last If Opened?
The paint can shelf life is over a decade, yet the paint can last a few years more. How much your paint can last after you have opened it depends on how you store it. You should check if the lid was closed fully. This is one of the most common mistakes.
Then, store the can in a dark place when the temperature is stable, not too hot, not too cold. Also, you should cover the paint with a thick cloth and plastic. All these tips will help to keep the paint in good condition.
Latex and acrylic latex paints are commonly used for house painting. These paints are easy to remove and are less toxic. However, it is good to manage carefully and save them in a safe place.
How Do You Make Old Paint Usable Again?
Before trying to make the paint usable again, you should check if the paint has dried, have a layer, the components are separated, and if it smells bad. Then, if you consider you can bring the paint back to life, you should follow these tips.
- If the paint has a dried layer, remove it with a stir stick.
- If the paint is separate, stir with a stick until all the components have mixed. If the paint remains chunky after mixing it, you shouldn’t use it.
- If the pain is dry, add a solvent until you get the right consistency.
Which Is the Best Paint for Home?
People prefer latex paints for interior painting because they are less toxic than others. Moreover, you can remove latex or acrylic latex paints with soapy water! However, they can irritate the skin, and some people are allergic to latex. Also, the fumes can irritate the respiratory tract when they were saved for many years; though, they do not poison.
To paint your house, remember to check the paint can warnings and if it is appropriate for inner paint. Also, carefully manage the paint, use a mask if you need it, and never manage paint if you are pregnant. Paint fumes can be dangerous during pregnancy, and some paint types can cause congenital abnormalities in the kid.
The Best Paints for Interior Painting
Here are some of the best paints for the wall interior. These paints are safe and less toxic in the market, so you can use them in your home without being worried about any health issues. However, you should always keep in mind that not everyone reacts the same to the chemicals, so take precautionary measures to manage any kind of paint.
Rust-Oleum Milk Paint Matte
Rust-Oleum Milk Paint Matte has a smooth finish and intense colors that will give your home walls a premium finish. It comes in a white shade, and it is water-based paint. Moreover, Rust-Oleum Milk has an affordable price.
PRESTIGE Paint is an acrylic-based paint perfect for outside painting. Moreover, it has a smooth finish and high color coverage. PRESTIGE Paint is expensive, yet you will have a premium product.
