Skip to Content

How to Remove Thinset From The Subfloor [4 Ways of Removal]

Are you on your new house project? Thinking about applying new tiles on your subfloor?

Then you must remove the existing thinset which is sitting on the subfloor. 

How to remove thinset from the subfloor?

It’s not that hard to remove the thinset from the subfloor. Using hot water and vinegar is really effective. If you have power tools lying around such as an angle grinder. You can use it to chip the thinset off. There is a possibility of damage to the subfloor. So be careful. 

This little guide may not be able to clear all your confusion. To get a detailed guide, follow the article till the end.

So let’s get in the things you’ll be needing and each method step!

Is It Hard to Remove the Thinset of the Subfloor?

Removing thinset from the subfloor can be hard but not always. With the right method and right tool, it can be done easily. They are made for tiles to stick to any surface. But thinset tends to not stick well on wood. So do avoid the wooden walls.

4 Ways to Remove Thinset from Subfloor

There are many ways to remove thinset from the subfloor. We have listed 4 of the easy and effective methods of thinset removal. 

Chipping Thinset With Warm Water

This seems to be the easiest method to remove thinset. You need really basic tools to chip the thinset. 

Things you’ll be needing:

  • Half gallon of warm water
  • Putty knife
  • Hammer
  • Angle grinding tool (optional) / sandpaper

A half-gallon of water will cover around 10m2 or 107 square feet of area. 

Steps:

  1. In the half-gallon of water, mix 1 cup of vinegar. This will weaken the thinset. 
  2. Hole the putty knife at a 45-degree angle and hit it on the back with the hammer.
  3. Sharpen your knife or clean the knife if it has loosened the sharpness
  4. Remove the remaining thinset with the angle grinding tool. Or use sandpaper if you don’t have one.

This process is really easy and simple. It doesn’t require too much hard work.

Hammer Drill Method

The hammer drill is a type of drill that has a flat hammer-like drill bit. 

Things you’ll be needing:

  • Hammer drill bit
  • Chisel 

Steps:

  1. Attach the hammer bit on the drill and hold it at a 45-degree angle
  2. Lower the angle if the thinset is hard or thick at someplace
  3. Gently break the thinset
  4. Use the chisel to remove smaller pieces of thinset afterward.

This is a much harder process than using hot water and vinegar. 

Angle Grinder Removal

If you have an angle grinder lying around. This is the best option for you. 

Also, the grinder tool is the only thing you’ll be needing for this method.

Steps:

  1. Get your angle grinder and change the existing blades if it is dull
  2. Replace the dust shroud or dust protector if you need to
  3. If you also have a vacuum cleaner lying around. It is better to attach it right now. Although this is not a necessary process. 
  4. The next step is really easy. Hold the blade as flat as possible and grind on the thinset

Even though this process sounds really easy, there is a possibility of damage to the subfloor. So be careful when you’re working with a grinder tool.

If you are thinking to buy an angle grinder, here are 2 which we recommend for various use:

Product-1
Product-2

These angle grinders are really for doing construction work. Such as cutting ductwork. Also, they are made with good materials. 

Thinset Removal With a Blade

It’s not a conventional method of thinset removal. But, if you cannot use other methods. You can give this a shot. 

Things you’ll be needing:

  • Sharp edge scraper
  • Sandpaper

Steps:

  1. Use the sharp edge scraper to scrape on the thinset.
  2. Use sandpaper to make any surface smooth. 

Try not to scrape a place if you cannot get all the thinset. Use sandpaper instead. The sandpaper can get down to a really small part and take the thinset out.  

How to Prevent Damaging the Subfloor While Thinset Removal

It is really easy to damage the subfloor. Most of the time the subfloor will be made out of plywood. And if you are using any power tool. It is really easy to scrape a part of the wood off. 

Use power tools on low power at the beginning. If you are new at this please try the tool out on a separate piece of wood or surface first. This will give you some practice. 

Also, use the method which is best for you. You don’t need to buy an expensive piece of the tool just because you need to scrape the thinset off. 

Don’t use thinset to fill a large gap on the subfloor. It will damage the subfloor. It will become too heavy to support above weight. 

To avoid any damage on the subfloor. Do practice on a corner or another surface at first. If you don’t feel confident using the tools or doing the job. Then consult professionals. 

FAQs

Are the power tools easy to use?

Answers: The power tools do have a learning curve. Practice on other surfaces before using it on the subfloor. 

How long does it take for the thinset to weaken when hot water is poured?

Answer: It takes 30 minutes to an hour. Use more vinegar if it’s working.

What kind of vacuum to use with an angle grinder?

Answer: Use a 5 horsepower wet-dry vacuum. Using a wet vacuum is really important. Otherwise, water will damage the vacuum.

Endnote

That is everything you need to know about, how to remove thinset from the subfloor. Hopefully, that cleared up your confusion. 

Always contact professionals if you’re not feeling confident.

Till then, good luck with your house project!