Make a Flagstone Patio

Stephen Scott Johnson
by Stephen Scott Johnson
10 Days
With the kids leaving the nest, my wife and I decided to get rid of the trampoline. That left a huge circular void in our backyard, a place that invited Martians to land. So we came up with the idea to create a flagstone patio.
It's a challenging project, but I saved thousands doing it myself.
First you need to check with your doctor and make sure you are up for this. It's a physically demanding project if you DIY. Some of these stones may be over 100 pounds and you may need help lifting them and placing them. Unless you rent mechanized equipment, expect to do some digging and shoverling. And yes--you might want to wear a back brace.
First select a suitable site. Preferably one that is already fairly level. Consider subdivision covenants and/or county requirements. Get away from the house or other structures if you want to add a fire pit. Consider privacy and what your neighbors think.
Create a level and compact soil base that is 3 to 4 inches below grade. I built my patio on a slope so I had to first build a retaining wall. It was hard work, but relatively easy to build. Use bags of crush & run to build a footing, and then make sure that first set of blocks are level. Then stack them. However, you may not need to do this if you pick out a level spot. I got my blocks from Home Depot.
Add a 3 - 4 inch layer of crush run and compact it. Use a hand tamp or rent a gasoline-powered tamper for faster results. Use strings to make sure you are getting your base good and level. You could have the crush run delivered. I made about 5 runs (truck loads)to the landscaping store to have enough.
Work with your local landscaping stores to select your flagstone. Give them the area you are working with and they can estimate what you need. I needed 2 pallets and had them deliver the stones right next to my patio site (a big back saver) I recommend going with the 2 to 3 inch thick stones for a patio. Being that thick they are much less likely to wobble or move. Also, pick out the color you want. They do vary in color somewhat.
I elected to build the fire pit first and then added flagstone around it. You may not want a fire pit for your patio. I do have a separate tutorial on Hometalk for the fire pit if you are interested. BTW, I bought the fire pit kit from Lowes.
Begin adding the flagstone, one stone at a time. It's like building an enormous jig saw puzzle. Adjust each stone and use the level for each one and to make sure neighboring stones are flush with each other. Take away or add crush run to adjust height of the stone. A simple process, but yes very tedious.
Here I am leveling and comparing stone to stone. Each neighboring stone. If you want your patio to have a slight pitch to it that's totally okay. Just make sure the stones are even with each other so you don't create a trip hazard.
Use a sizable hammer to chip off jagged edges or sharp points. Make sure you wear safety glasses. Flagstone is very easy to break and shape to make stones fit gaps and follow the contour of the other stones. I found this 5 pound hammer at Lowes or Home Depot.
Tamp around the edge of each stone and make sure it's well seated in the crush run. As a final test for each stone, stand on them to make sure there's no wobble. If you detect wobble, keep working with it to make sure it has a good solid base.
Stones are all in place. Now it's time to fill in the gaps. BTW, it's okay to have 1 to 2 inch gaps between stones. But you may want to place the stones for a tighter fit. That would mean you would need less filling matter. I DO NOT recommend concrete because you're building this patio on a crush run base. Concrete would eventually crack if you used it to fill the gaps. Now, if you built it on a concrete base, you might be okay with concrete in the gaps.
I used something called M10 to fill the gaps. M10 packs well and is not as prone to sustain vegetation growth. It's a very fine gravel--almost like a mixture of gravel and granite dust. A truck load is all I needed.
Broadcast the M10 out over your patio with a shovel. Then use a push broom to move it into the gaps and cracks.
Using your hose with a spray nozzle attachment, lightly spray over the patio. This will encourage the M10 to settle down into the gaps. You may want to repeat this step a couple of times, until the M10 is nearly flush with the stones.
And you're done! Invite friends, family, neighbors and have a party! But you might want to rest and recover first. Or make a visit to your Chiropractor - LOL. This project took me several weekends to complete, but I saved thousands doing it myself.
Stephen Scott Johnson
Want more details about this and other DIY projects? Check out my blog post!
Frequently asked questions
Have a question about this project?
3 of 4 questions
  • Beki Bowen Beki Bowen on May 30, 2018

    We did this too. However, we live in the Texas Hill Country and it is hot as......blazes!!! What can you do to make this cool enough for kids to walk on bare footed? Ours is around the pool.

  • Kelly-n-Tony Kelly-n-Tony on May 21, 2019

    I've considered a project like this as well and wonder how any chairs will slide/move on the surface. Will they be easy to move or get stuck or wobble with the difference in the stones and the M10 gravel?

  • Tiffany Tiffany on Mar 01, 2021

    Hey there, how did you determine the amount of M10 you would need? And in the event that itcdries, and I'm wanting to add more, is that ok?

Join the conversation
4 of 46 comments