How to Dispose of Polyurethane Varnish?

Polyurethane varnish, which can be water-based or oil-based, does go bad over time.

In that case, you won’t be able to use it, and you must get rid of it. Varnish can be toxic, posing a risk to the environment.

Therefore, you must dispose of it properly so that you don’t put wildlife in danger.

There is more than one way to dispose of polyurethane varnish. This comprehensive guide explains what you must keep in mind.

Steps to Dispose Polyurethane Varnish

Here are the things you need to do when disposing Polyurethane Varnish

Step 1. Check the Label of the Varnish

It’s best not to throw out the varnish cans when you store leftover varnish.

This way, you can always check the ingredients list on the label.

Look at the Ingredients List to Determine How to Dispose of It

The ingredients list will tell you exactly which chemicals are present.

You can then use that information to dispose of or recycle the varnish according to appropriate guidelines.

Step 2. Contact Your City’s Waste Management Department

Contact your city’s waste management department and mention that you plan to dispose of polyurethane varnish.

Ask the representative if there are any city or state rules and regulations regarding the disposal of the ingredients in your varnish.

Make Sure to Follow All Specific Guidelines

The waste management department may provide some specific and detailed guidelines. In that case, you must follow them exactly as the guidelines say.

Failure to follow lawful practices of waste disposal can result in penalty fees.

In some cases, you may even have to spend money on attorney fees. So, it’s best to be careful from the very start.

Step 3. Set Up a Pick-Up or Drop-Off Appointment

You can schedule an appointment to have the leftover varnish picked up from your home. If the waste management department does not pick it up, drop it off at the appropriate place.

Be sure to put it in the appropriate packaging so that it does not make a mess. You must also place it in the correct disposal bin.

Failure to do so can damage sorting material or increase sanitation workers’ work.

Also read: How to Dispose of Stain Rags?

How to Dispose of It Yourself in a Safe Manner

In some cases, the waste management department may leave the disposal up to you entirely. Thus, you can try a few ways to dispose of it.

All of these ways won’t put a risk to the environment.

These methods of disposing of polyurethane varnish involve drying it out. Varnish poses a danger to the environment when it is wet.

Therefore, you can speed up the drying process in two ways.

Method 1 – Dispose of Polyurethane Varnish Using Kitty Litter

It’s safe to dispose of polyurethane varnish using kitty litter. This is because kitty litter is hygroscopic.

Therefore, it absorbs the polyurethane varnish and clumps together.

Therefore, it won’t let the varnish get into contact with other animals and the environment.

Wear the Appropriate Attire

It’s best to wear appropriate attire when dealing with varnish to prevent it from getting onto you. You should wear a long sleeves shirt to keep your arms from getting stains.

At the same time, you could consider wearing a pair of latex gloves. That will allow you to handle all material with ease.

You can also then work without fear of anything getting stuck under your fingernails.

Wearing a pair of goggles is not required. However, if you are afraid of varnish splashing into your eyes, you could wear them.

Combine the Polyurethane Varnish with Kitty Litter

Transfer an equal amount of kitty litter as the varnish into the can.

If you suspect that is not enough to dry the varnish completely, add more kitty litter to the can.

Use Another Container if the Can Is More than Half Full

If you have more than half a can of varnish left, you could pour the varnish into a trash can or a lined box.

Make sure the can or box is larger than the varnish can.

After that, you can transfer the kitty litter into the trash can or lined box. This process will give the litter enough space to absorb the varnish without spilling.

Let the Mixture Set

Kitty litter will take some time to absorb the polyurethane varnish completely.

Therefore, you must let the mixture sit for at least one hour.

Use a ladle or other tool to stir the litter and the varnish during that time. This will quicken the interaction between the two materials. As a result, the litter will absorb the varnish quicker.

You should also leave the lid of the can off. Exposure to air will help speed up the drying process. 

Check the Mixture to See if There’s Still Liquid Varnish

After an hour, use the ladle to move around the mixture in the can. Inspect it closely to see if there’s still liquid varnish in the can.

Add some more kitty litter in the can if all of the varnish has not dried up.

Stir the mixture once again and let the mixture sit for another 10 to 15 minutes.

You can then inspect once again to see if all the polyurethane varnish has dried.  

Throw the Mixture into the Garbage

You can throw the mixture into the garbage after it dries completely. You do not have to leave the lid on the can.

The polyurethane varnish will not pose a risk to the environment in that case.

Using kitty litter for disposal is an effective and relatively inexpensive method. You won’t need much kitty litter, and the product itself is affordable.

Method 2 – Dispose of Polyurethane Varnish Using Newspaper

You can also dispose of polyurethane varnish using newspaper. This option is good if you have a lot of varnish to get rid of. It’s a more inexpensive option than using kitty litter.

Using newspaper can be more time-consuming than using kitty litter, however. Newspaper won’t absorb polyurethane varnish as readily.

Therefore, be sure to put a lot of newspaper into the can of varnish.

Move the Newspaper Around to Ensure It Gets into Contact with the Varnish

You will have to move the newspaper around in the can to ensure it gets into contact with the varnish.

Let the newspaper sit for about an hour and check whether the can is dry.

If it has not dried, keep adding more newspaper until there is no liquid in the can.

After that, you can throw it in the trash or ask your waste management department how to proceed.

Method 3 – Dispose of Polyurethane Varnish Using Commercial Varnish Hardeners  

You can also use commercial varnish hardeners to dry out the polyurethane varnish. It works fast, but it can be costly.

So, you should only consider this if time is an issue.

Method 4 – Let the Polyurethane Varnish Dry on Its Own

If you don’t have time constraints, you could let the polyurethane varnish dry on its own. All you have to do is leave the lid open and let the air do the trick.

This process can take a while until the polyurethane varnish is ready to throw out. You could keep it in a place where there is adequate sunlight to save some time.

When choosing this method, be sure not to leave the cans lying around anywhere. You must pick a spot of your home where pets and children can’t access it.

In any of the four drying methods mentioned, you must ensure that all cans and rags are completely dry before throwing them out.

You must be extra careful when dealing with oil-based polyurethane varnish.

Oil-based polyurethane varnish is highly flammable. Therefore, it can catch fire in the trash if you’re not careful.

That said, it’s safe to dispose of after all of the cans, rags, and other materials are dry.

Consider Recycling the Polyurethane Varnish

You can also consider recycling water-based polyurethane varnish. You can contact your local recycling company and drop it off there.

This is a good option if the polyurethane varnish is still useable. It also means that you don’t have to go through the lengthy process of drying the varnish.

The recycling company will handle all of that for you.

If the polyurethane is not useable, the recycling company can break down the components of the polyurethane varnish.

It can then use the ingredients in the production of other goods.

Last Few Words

There are a number of ways to dispose of polyurethane varnish. However, you must choose the method that is safest for the environment first.

Moreover, you should always consider recycling before disposal.

If you have useable polyurethane varnish, get in touch with local non-profit organizations. They can take it off your hands and provide this resource to those in need.

If you can’t find one, ask friends and family if they need the varnish for their homes.

Other articles you may also like: