How to Install Pavers Over a Concrete Patio Without Mortar

Paver patio

I have a small poured concrete patio, and that I’d like to cover with brick pavers. Can I do this without using mortar?

According to several paver manufacturers, paving blocks can be installed on top of concrete without mortar if you first lay down a 1/2″ to 1” bed of coarse sand. The process is nearly identical to laying a paver patio over ground.

However, this type of installation should be done with caution, since drainage, settling, and cracking can be a problem. Keep these tips in mind when laying pavers over a concrete patio:

  • Drainage: The biggest problem with laying pavers over a concrete slab is the inability for water to drain through the blocks and down into the earth. Before you begin, make sure your concrete is properly sloped and doesn’t puddle. Keep this drainage slope in mind when adding your pavers, and make sure the edge that drains water stays low and permeable. You can also drill small drainage holes through the concrete every few inches, to help any puddling water seep into the ground.
  • Sand in Joints: When you’re finished laying the blocks, firm them up by filling the joints with polymeric sand. While sand joints are still permeable, if properly set they can help excess water run off the surface rather than puddling.
  • Edging: Like any other type of installation, a concrete slab paver patio needs to be firmly edged, to keep the sand and pavers from settling and squishing around. However, your edging needs to allow for water to drain; if it’s watertight, your patio could turn into a bowl of water when it rains.
  • Red brick pavers

  • Semi-Mortared: Rather than dealing with edging, some builders use mortar or adhesive to hold the perimeter course of pavers in place. To do this, you’ll need a clean perimeter around the sand bed, so the blocks can stick directly to the concrete. Make sure the mortar and sand bed are the same thickness, so the blocks will be level. This method can create a nonpermeable edge that could cause water to puddle under the pavers.
  • Height: Your new patio will be up to 3” higher than the original concrete slab. Be sure to plan for transitions to other areas, especially if the patio adjoins your house. Most building codes specify how far a masonry patio should be from a home’s siding, and you may need to install flashing to keep water away from the house.
  • Concrete Condition: If the concrete slab is broken or in terrible shape, you might be better off ripping it up and starting over.
  • Not for Driveways: In general, this isn’t a good method for driveways. The underlying concrete doesn’t allow for the pavers to give, so they’re more likely to rock and crack.
  • Patio Extension: You can also extend the size of your patio, by digging out the soil around it and installing a proper gravel and sand bed, then screeding and tamping the sand across both the old and new areas to make it level. However, keep in mind that the non-concreted areas will be more likely to settle, and over time your patio may become uneven.
  • Don’t Rule Out Mortar: If you’re new to this project, don’t be intimidated by the prospects of mortaring a permanent paver patio. In my opinion, mortar would be less work!

Julie

Further Information

17 COMMENTS

  1. Re. Julie’s article on installing pavers over concrete.

    I plan to do this on the walk leading to my front door. The existing concrete (in good condition) like many other sidewalks consists of a series of 3 foot sections. If these are expansion joints, the groove is only a half inch deep. The question is can I go over these joints with pavers? Do I have to avoid going over these joints when I set the edge using an adhesive or mortar? Thanks. Doug

  2. I’m laying pavers over my existing concrete patio. I have mortared in the two sides, but left the front of it unmortared to allow for drainage. I planned on building the soil level up a little here so that it allows drainage, but also some restraint. Does this sound like a good method? If not, what do you suggest? Thanks, Joe.

  3. Another area to consider when making lawns and gardens look great is professional concrete curbing. I haven’t read any articles here that speak about it. Curbing will really enhance the look and feel of your property, either residential or commercial. Installing concrete curbing is what we do and it makes all the difference.

  4. Hi Danny,

    Thank you for providing this service to home owners.

    I’m the second owner of a townhouse and pavers were added to the concrete patio in approx. 1996 (I’ve lived in the house 6 years). The pitch from the middle of the patio has changed and its slopping toward the house and now my laminate floor is warped because of the moisture from the water absorbed by the concrete slab my house is built on.

    Since I’ve lived in this house from spring thru fall, high powered sprinkler have been saturating the patio and vinyl siding,leaving puddles of water all over patio.

    Also, the paver stones by the wall of the house are all lifted up or sunken down. There are 3 brick borders edges around the patio but not at the edge of the house where the sliding door is, instead the is about a 1″ space between the pavers and the wall.

    The question: would almost 19 years of water saturating the patio and the house cause the downward sloping of the patio and the pavers to shift and come up and sink down? The homeowners association is responsible for outside maintenance and the sprinklers and they are trying to shift the responsibility for this issue. I would appreciate any information you can provide. Thanks.

    Dee

  5. Dee, I think you need an attorney. I am living testimony to the effects sprinklers can have on on structures. For six years I wasn’t particularly careful about water hitting the wood fence that borders my backyard garden. By last fall the cedar posts needed bracing to keep it upright, and this summer I had to replace it–to the tune of $7,000. Good luck!

  6. I want to put a step outside of my French door. It is paved area. What do I put down first before I lay the bricks and then the paving slabs? I am a lady of 71 and I would like to have a go at this.

  7. Is there a way to drill drainage holes in an existing partically cover patio. The patio is concrete cover with porcelain tiles. When there is a heavy rain, the water puddles in areas and runs across part of the patio. The patio has a stone wall on one side and the water collects in area against the wall.

  8. My landscaper installed pavers over my existing patio using a sand base and filling the spaces between with sand…then the rains came and leached water up to the stucco on the house. They drilled about 60 holes in the patio, layed the pavers over sand again and now the monsoon season in New Mexico is here…needless to say, water is leaching up to the house and staining the stucco….what should be done to resolve this problem? My landscaper says this is normal and especially on a patio facing north. I say this could ultimately result in stucco damage as well as other structural problems…any suggestions?
    Thanks

  9. I have cool deck over concrete around my pool. It is not is bad shape but looks old. What is the best way to spruce this up and make it look new again?

  10. I have an uncovered patio that used to have outdoor carpet. After mulitple demo efforts, there are still traces of carpet glue residue and water pools in the center. The patio is surrounded by the brick walls of our house on three sides and a short drivet wall on the fourth. I’m looking for an inexpensive solution that will be slip resistant and won’t trap dog hair from my shedding Shepherds. I am open to removing the short wall. This seems quite hopeless without a huge budget. I have 1/3 of the patio covered in recycled rubber pavers as a test area – this was a miserable failure since it requires daily shop vac to remove all the dog hair. Any suggestions would be appreciated!

  11. I have just signed a contract to have pavers put around my pool deck. I asked that he use polymeric sand & he said I didn’t need it on a concrete deck base. What do you think?
    Regards
    Lauretta

  12. My house is 97 years old and sits on the corner at the intersection between two streets. The concrete walkways to the street at the front of the house and the one to the street at the side of the house are old and pocked, and so are the two or three steps that go down to the street level. After thoroughly scrubbing this old concrete with a rotary wire brush attachment on a Rigid angle grinder, I used Quickcrete patching material to patch the pocked areas in the concrete. Then I used masonry adhesive from Lowe’s to glue a course of 4 by 8 by 1 inch thick brick pavers placed perpendicular to the edges of the walkways. I placed small round globs of the masonry adhesive at six points on the bottom of each brick paver so that there would plenty of space for rain water to drain out between the pavers and the concrete surface underneath. Then I cut heavy black construction paper to fit in two layers between the two courses of brick pavers on either side of the walkway–a space 24 inches wide. Then I spread a thin layer of sand over the black paper and proceeded to cover the black paper with a basket weave design of brick pavers. It all fit together just perfectly without doing any cutting. (I did have to do some cutting to cover the steps going down to street level and at the porch steps.) then I spread polymeric sand over the surface and brushed it carefully into all of the small spaces between the brick pavers. I sprinkled the whole surface with water to wash as much of the sand as possible into the spaces between the brick pavers. Using the same procedure I covered the concrete patios at two entrances into the house. That was two years ago, and things have held together beautifully.

  13. Do you have any photos of before & after for the “sand over concrete” pavers install.

    Also, any photo examples of a few years AFTER the work was completed?

    I’m a visual person. Seeing an example & perhaps the steps would simplify the “how to do this is;” particularly in my mind.

    Sounds like a great idea! I can’t wait to see & try it out!! Thank you

  14. i plan on installing pavers over an existing 24 x 24 concrete patio. Will I have a problem in winter with water getting under the pavers and freezing? I would add 1/2 – 1″ of sand under the pavers. Should I leave a means for water to drain at the end of the patio by drilling holes through the concrete every 6 ” in front of the mortared border at the low end of the patio

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