How to Repair a Cobblestone Paver Patio

It may be necessary to repair a section of a cobblestone paver patio from time to time. Everything from old age and exposure to weather to accidentally dropping a heavy item can cause damage to paver patios. Whatever the case, small repairs are easily accomplished. Cobblestone patios with mortared joints will require more work, but most patios made with this versatile material are packed into place, not mortared, so the repair is relatively quick.

Tools and Materials:

  • Replacement cobblestone(s)
  • Rubber mallet
  • Masonry sand
  • Level
  • Chisel
  • Hammer
  • Thin, durable tool like a putty knife
  • Mortar and trowel (optional)

Step 1: Remove Cracked or Damaged Cobblestone

If the stones are packed but not mortared, loosen and remove the stone. You might insert a putty knife into a gap to pry it free. If the paver is cracked in two, chances are it is already loosened, so removing it shouldn't be too difficult. If the stone is mortared into place, take the chisel and hammer and free the stone by firmly chiseling away at the mortar. This is a bit more time consuming. Be careful not to damage surrounding stones.

Step 2: Prepare a New Foundation

Pour a small handful of masonry sand into the exposed space. Smooth and level the layer of sand with your hand. For mortared stones, clear away the mortar that is hardened to the surrounding cobblestones. Tap at it gently with the hammer and chisel. Once again, be cautious of accidentally breaking another stone. You'll want to use some sand to provide a bed for the new stone in this case as well.

Step 3: Set the Replacement Stone

Take the replacement cobblestone and set it upon the bed of sand. For both packed and mortared stones, make sure there is an equally-spaced gap on all sides of the stone relative to those surrounding it. There should be enough sand so that the stone sits slightly above the level of the patio, but not too high. If it sinks below the surrounding stones, remove it and add sand. If it's too high, remove it and pull some sand out.

Step 4: Tap into Place with the Rubber Mallet

Once you're happy with how the stone is sitting, take the rubber mallet and begin to gently pound on the cobblestone to cause it to sink into the bed of sand. Don't pound it violently or the stone could crack. Then again, don't pound it too lightly unless you're simply trying to finesse it into place.

Step 5: Check the Level

Place the level on the stone in several different places. Check that it's level widthwise and lengthwise. You may have to add or pull out sand to raise or lower a single corner.

Step 6: Stabilize the Stone

Once packed, take a handful of masonry sand and fill all of the gaps surrounding the stone. Use enough to completely fill in the spaces. Go higher than the level of the patio, for you'll eventually hose it off, and you want the sand to settle at surface level. If you're using mortar, mix up a small amount at the right consistency and fill the gaps. Use the masonry trowel to pack it in and properly smooth it to match the surrounding stones. Allow mortar to fully cure before applying weight to the repaired area.