
For those who have spent hours painting their own home, getting rid of the excess wood stain, paint, and varnishes seems to be as easy as pouring it down the drain.
Of course, you do not want to pour the stain and varnishes down the kitchen sink drain as that will clog the pipes.
However, some either do not know or have a moment of forgetfulness, and suddenly, their pipes are clogged with paint.
Since paint is designed to cling to surfaces, it will quickly start to harden. This means it will stain PVC pipes even after most of the paint is removed.
Tiny amounts of paint, such as those that may be on your paintbrush, may not cause much harm to your pipes.
But pouring the stain and polyurethane varnishes down the drain is another matter.
What Happens if Wood Stain Goes Down the Drain?
If you accidentally pour the stain or varnish down the drain, it will stick to the inner walls of the drain.
This will cause the grease, hair, dirt, and other particles that generally flow through the pipe to become stuck to the inside.
It will not take long before the drain is clogged up with so much material that water will start to back up. In addition, the type of paint primer and stain will affect the pipes.
While a bit of latex paint tends to be water-soluble, it is still a threat to clog up the drains if enough is poured into the pipes. Oil-based enamel paints are much more difficult to remove as they will resist water.
If there is any good news, it is that wood paint, epoxy, or poly clogging the pipes is a common enough problem that there are readily available solutions.

Removing the Wood Stain and Varnishes from Your Drain Pipes
Because not all sink drains are alike, different techniques are available to remove the wood paint from the pipes.
You should try the following ideas one at a time. Follow each technique step by step for the best results.
If one technique does not work, try another. You may have to call a professional to rid your drains of pipes if none of the techniques work.
1- Dissolve
Paint thinners are designed to dissolve the paint and are usually the first product people think of when removing paint.
However, before pouring paint thinner into the sink drain, there are issues to consider.
The first is the environmental impact of putting paint thinner into the sewer system.
Many communities have laws against pouring dangerous chemicals down the drain.
It can mix with other materials and may create a dangerous situation. Check with your local laws first before considering using paint thinners.
A little paint thinner probably will do no harm. So, if it is legal for you to use paint thinner to remove a clog, try pouring a small amount down the drain.
This tends to work best on minor clogs or when you notice the water drainage is slowing down.
If the paint thinner is not working, try switching to baking soda. Since baking soda is not considered harmful, you can use more of it to try and remove the clog.
Another common household item that may break up the stain and paint is vinegar.
Like baking soda, vinegar is not considered harmful, so you can pour more of it down the drain.
2- Scrape
If you find that paint thinner, baking soda, and vinegar do not work, the next step is to physically remove the paint by scraping it away.
If the paint or wood stain is visible near the top of the drain, it is possible with the right tools to simply scrape it away using the proper force.
The first step is to unscrew the P-trap if the paint is visible but further away from the top of the drain. In some cases, you may have to remove the pipe itself before you can start scraping.
You can simply unscrew it at the connections if it is a plastic pipe. If it is a metal pipe, you will need a couple of tools, such as a wrench or pliers.
If you cannot see the paint, it is probably so far down the drain that you might as well start removing pipes until you can see it.
The next step is finding the right tool to remove the paint physically.
The most common tool used for this process is known as a plumbing snake or a drain snake. This is a tool often used for scraping out the inside of pipes.
You simply lower it into the pipe and scrap the sides for snaking.
For metal pipes, the drain snake may be used with some force, but with plastic pipes, you may need to be a bit careful.
When you reach the clog, start scraping away the paint until it is mostly removed.
Once the clog is gone and only a little paint remains, you can use a little paint thinner or baking soda to remove the remains of the paint.
However, life is rarely as simple as knocking away the paint with a drain snake.
In many cases, the clog is simply too far down the pipes for you to reach. If that is the case, the simple and more expensive solution is to replace the drain pipe.
If the clog is located in a section of the pipe that can be easily removed, it can be easily replaced with a new pipe.
3- Call Your Plumber
If nothing you do works, then you can always call a plumber.
They have the tools and experience to remove the paint and varnish from the inside drains and break up any clogs.
This may be the most expensive solution, but it will work.
If you do not want to bother with cleaning out the paint and freeing up the clog yourself, then call your trusted local plumber to do the job.
How to Dispose of Wood Stain, Paint, and Varnishes Responsibly?
Proper solutions to disposing of wood stains, paint, or varnishes start with keeping them in a can or container, drying them out (with cat litter or paint hardener), and throwing them in the garbage.
Before doing that, I suggest keeping a little of the paint around if you need to repaint an area of your home to match. Decide how much you want to keep, then seal it in a container for drying and throwing.
Alternatively, you can donate the leftover supplies or take them to a location where such disposal can occur.
The rest of the paint, stain, or rags soaked in solvents should be disposed of properly by going to a location that does such work.
Most communities have a waste disposal center where paint and other products can be taken when you need to get rid of them correctly without negatively affecting society.
Final Thoughts
The lesson is that you should never pour any product that might clog down the drains.
If you pour wood stains (paints, varnishes, waste paint water, mineral spirits, or paint thinners) down the drain, they can clog your sewage system, become tough to remove and make the environment toxic.
So, before you put even a tiny amount of these materials in your drains for quick disposal, think of the people and animals around you.
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Hi, I am Mark Garner a professional carpenter, woodworker, and DIY painter. I live in the small city of Peoria, Arizona as a semi-retired woodworker. I have started this blog with a simple motive to help you with my wood experience in this sector. If you like to know more about what I love doing and how it all got started, you can check more about me here.