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Why Does Paint Smell Bad?

Why Does Paint Smell Bad?

Imagine opening up a fresh new can of paint only to find it emitting a sour smell.

While paints usually emit chemical vapors, if it smells like rotten eggs, it has probably gone bad.

Bad smelling paint can result from improper storage, which can result in its contamination and expiry sooner than indicated on the packaging. Paint can also smell bad if it has expired, which changes the chemical composition of the substances inside.

If you still want to use the bad smelling bad, you should know that the vapors it emits will be more toxic that the fumes from normal paint.

Some people also have breathing issues and headaches resulting from regular paint fumes, so the paint fumes of expired paint can be only worse.

So, paint that smells unusually bad is indicative that it needs to be thrown out!

How Can You Tell If Paint Is Bad?

Paint usually has a distinct smell because of the volatile organic compounds (VOCs) that get released in the air when it begins to dry.

However, bad paint will have a foul, sour, or rancid smell that is extremely sharp.

At times, bad paint may also emit the smell of mold and mildew which will be indicative that the paint has gone bad.

Also, if you continue to use this paint despite the smell, it is possible that it might reduce, but this isn’t guaranteed.

If you become used to the bad paint smell over time, any new person entering the house will certainly point out the bad smell.


Does Paint Smell When It’s Bad?

Paints usually have a shelf life of 10 years or more.

However, if the latex has not been properly stored, paint can go bad even within a year.

If you feel that the paint has gone bad, you can go to the shop you purchased it from and demand a refund or exchange it for another tub of paint, as it has probably gone bad because of improper storage.

What Happens If You Use Rancid Paint?

Here are some issues that may occur if you use rancid and sour-smelling paint:

1. Uneven Application

It is possible that bad paint will not go over as smoothly on the wall as paint should.

Therefore, it will give a patchy and unfinished look to your wall.

Even if you are getting the house painted for getting the house on the market, or renting it out, the uneven coat of paint will leave a very bad impression, thus lowering the rental or selling value of your property.

2. Toxic Fumes

The effects of rancid paint are not just limited to a bad smell or odor.

Bad smelling paint means the chemical composition of the paint has changed.

Therefore, when its liquids evaporate into the air after applying to the wall, it will emit VOC fumes at a high level, which could be extremely toxic to the residents, including humans and pets!

3. Lower Paint Life

Another disadvantage of using rancid paint is that the longevity of the paint will be compromised even if the bad smell goes away or lessens somehow.

The paint will chip away at the surface even before it has reached its life’s end.

Before the chipping, it is possible that the paint may fade away in patches, making the painted wall look like paint was hastily applied.

What To Do If Paint Smells Bad?

If you have opened a paint to find out that it has gone bad, the only option is to replace it with new paint.

If you have already applied the paint to the surface, it is recommended that you scrape off the paint.

Nothing good can come out of paint that smells like rotten eggs. If it has applied, you need to scrape off the paint in order to provide a solid and even base for the new paint coat.

Here are step-by-step instructions to deal with applied paint that smells bad:

  1. Purchase a wire brush and remove the paint by swiping it over the surface. Try to sweep the brush in the direction of the paint strokes, if visible.
  2. Use a manual paint scraper to get rid of the rest of the paint. Even though this is a slow and tiresome process, there is no other quicker way to get rid of the foul smelling paint.
  3. Use the washed and dried wire brush again to get rid of loose paint from the scraping job.
  4. Scrape the wall with a pole sander and prime it with a primer before painting a new coat.

Make sure you are using safety equipment like a paint respirator to assure that you don’t get eye or lung irritation because of the rancid paint.

Summing Up Bad Smelling Paint

Paint jobs can add new life to a room or a house. However, if you find a bad smelling can of paint, you need to throw it out right away.

The bad smell probably results from the improper storage of the paint, causing it to expire early.

Using such paint poses a threat to the residents of the house, does not give an even and smooth application, and has a lower life than regular paint.

If you have already applied the paint, it is best that you remove it if possible in order to replace it with new paint.

But before that, it is important that you remove the paint completely and prime the wall with a primer before painting it again to assure that the new paint has a fresh wall and has a long life.

Lindsay Reed

Hi, I'm the founder of! I created this website to be a resource for everyone who wants to make the best home possible.