How To Fix Uneven Flagstone Patio

How To Fix Uneven Flagstone Patio

Uneven flagstone patios are a common problem. The stones can shift due to the weight of people walking on them, the frost, or any other number of factors.

In addition to being unsightly, uneven flagstone can also be slippery and cause injuries.

However, there are several ways you can fix this problem. Continue reading for some tips on how to fix uneven flagstone patio that will work for your situation!

One of the most common complaints people have about their flagstone patio is how uneven the stones are.

This can be frustrating, especially when there is a lot of pressure on your back to make everything perfect for summer grilling and hosting friends in your backyard!

Fortunately, fixing an uneven flagstone patio doesn’t need to be very difficult or expensive.

This blog post will go over how to repair an uneven flagstone patio by following very simple steps!

Why Is My Flagstone Patio Uneven?

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Image: Flagstone Trends

Typically, there are several reasons why your flagstone patio is uneven.

When it comes to how you can fix an uneven flagstone patio, the first step will be to identify why this has happened in the first place.

Here are just a few reasons that your stones may have become unbalanced:

  • The ground underneath your slabs might not have been leveled out before installation. If this is the case, it will be necessary to level out the ground to lay down a solid foundation for your slabs.
  • The stones might have shifted due to settling or weight from people walking on them over time. In this situation, you won’t need to do much other than add some additional support by adding risers underneath each slab.
  • Your flagstones could have been installed when there was frost present in winter that caused movement throughout the winter months and with changes in weather during spring/summer seasons!
  • The patio may have settled over time and is no longer level. This can be a tough situation, but you might be able to solve it by adding more stones on top of the existing slabs or removing some if necessary.

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How To Fix Uneven Flagstone Patio

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Image: Flagstone Trends

If you have an uneven flagstone patio, there are some simple repairs that can be done to level it. You need first to determine the cause of the problem.

Look at how your stones were installed – do they look ok? If so, you may just need to replace a few stones or add more gravel underneath them for support.

If not, you’ll need to remove all of the old mortar and start with new mortar!

What You Will Need:

  • Level mason string line
  • Rubber mallet/sledgehammer (for larger slabs)
  • Trowel or flat shovel
  • Mortar Mix (premixed) or sand/concrete mixture
  • Paving stones & bricks for support
  • Polymeric sand
  • A large bucket of water

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How To Fix Uneven Flagstone Patio Step By Step Instructions:

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Image: Flagstone Trends

Step 1: Clean your flagstones!

When trying to fix an uneven flagstone patio, start by clearing off the old mortar. If the mortar is stuck, remove as much of this as possible using a hammer and chisel.

Once done, wash down each stone thoroughly so that later steps will be easier for you!

You can use mild soap mixed in water or even TSP cleaner if need be. Make sure not to damage any stones during this process either!

Step 2: Level Out Your Patio Base

Once all slabs are clean, level out the ground where they are going to sit before laying them back down onto new mortar.

This will make putting your stones back down more effortless as the base has already been leveled. If you don’t level out the ground, it could become unbalanced again very quickly!

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Step 3: Mix Mortar

Mix mortar according to the packaging instructions. Or, just mix it with water if you are using premixed mortar, which is easier!

Remember how much joint compound or sand depends on how many stones you have and how big they are – so follow directions provided for your specific type of grout/mortar.

For smaller jobs where you only need a small amount, use polymeric sand instead as it sets better than regular dry sand alone. 

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Image: Flagstone Trends

Step 4: Lay Down Stones & Add Risers (if necessary)

Lay down stone after stone onto new mortar following the lines laid out by mason string line (to keep things nice and even).

Use bricks underneath larger slabs for how to repair an uneven flagstone patio as they need additional support.

If you have a lot of smaller slabs, then just use the bricks underneath them all to maintain how much weight is being placed on each slab!

Step #: Clean Stone & Finish Job

Make sure everything is clean, and even before finishing, level out the flagstone patio with polymeric sand or another type of sand.

Once done, water down your stones again to clean any excess mortar off of them using a garden hose. Your stones should now be ready for use once dry!   

Frequently Asked Questions

What Are The Best Stones To Use For Flagstone Patios?

The best stones to use for flagstone patios are typically fieldstones. They have nice, flat surfaces that are easy to install and look great in most landscapes!

What Is The Typical Weight Of A Flagstone Patio?

The weight of a flagstone patio varies depending on how much mortar is underneath it. And what type of stones are used. Typical weights can range anywhere from 12 pounds to 50 pounds per square foot, or roughly 100-400 lbs for an average-sized patio!

How to fix an uneven flagstone patio?

The steps needed to fix an uneven flagstone patio depend on what caused the original problem. If it was just poor installation, you can simply clean off any mortar stuck onto stones and level out part of your base with gravel/sand before putting down a new joint compound or mortar.

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Image: Flagstone Trends

The process of fixing uneven flagstone is very simple, but it does take some time.  The best way to install flagstone is by first leveling the ground underneath it.

This will help to prevent any future problems with your stones shifting around! If you have problems with an uneven flagstone patio, follow the above steps on how to fix uneven flagstone patio.

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  • Ricky

    Hi, I’m Ricky. I’ve been involved in lawn care and landscaping from when I was 15. To be honest, I didn’t like the idea of pushing mowers, collecting grass clippings, and maintaining flowerbeds at the time. But having seem the passion my parents had for gardening and outdoors and the effort they put in maintaining the health and beauty of our landscape, I couldn’t help but not only admire their hard work but also I became a part of it. As someone who loves to spend time with nature’s best, I find myself learning a lot more about gardening and outdoors on a daily basis. Not to mention I love to share the knowledge I’ve gathered over the years with my readers at We Mow Dallas. To be clear, I don’t have a Master’s degree in gardening or anything like that. Everything I’ve learned about gardening, landscaping, and lawn care spring from passion and engagement with my parents. And with a ton of free information out there, plus the ability to run tests and determine what works best for lawn care and landscaping, every day is an opportunity to learn and implement something new. My goal with We Mow Dallas is to teach you exactly how to maintain your lawn and landscape. And since I walk the talk in reality, you shouldn’t hesitate to join me in this wonderful world of landscaping and lawn care. K Beatrice

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