How to Lay Natural Stone in Wet Mortar

Natural stone has many shapes, sizes and colors due to it being weathered by nature.

Natural stone has many uses, and a few varying ways of installing it. One choice would be to dry stack the stones. Another choice is to use wet mortar which will reinforce the stone structure being built. Properly laying natural stone can prevent and virtually eliminate cracking and crumbling of mortar. It takes time for the mortar to crack but laying the natural stone in wet mortar the first time will reduce the chances of having to do it again later.

Things You'll Need

• Dry mortar mix
• Water
• Mixing container (5-gallon bucket)
• Trowel
• Notched trowel
• Natural stone
• Wire mesh (only on walls)

Instructions

1. Mix the mortar with water according to the manufacturer's directions. When properly mixed the mortar should be the consistency of cake icing. When placed on an upside-down trowel, the mortar should not fall off.

2. Smooth out a ½-inch-thick layer of mortar onto the surface where the stone will be installed. If the stone is going to be installed on a wall, tightly wrap the wall with wire mesh first.

3. Run a notched trowel through the wet mortar to create a groove for the mortar on the stone to bond with.

4. Butter the first stone to be placed by layering mortar on the bottom of it approximately ½ inch thick.

5. Press the stone into the mortar and wiggle it back and forth to settle the two layers of mortar into each other. Mortar should ooze out from under the stone. Wipe the excess away using the trowel.

6. Layer the top and sides of the first stone with mortar.

7. Repeat steps 4 to 6 until all stones have been placed. Place the next row of stone, centered over a joint between two stones in the row below.

8. Allow the mortar to dry for 30 minutes. It should not be completely dry. When touching the mortar after 30 minutes it should leave a fingerprint.

9. Brush the mortar between the joints smooth.

Tips & Warnings

• Always wear gloves when working with the mortar.

• Wear eye protection, and a face mask to prevent inhalation of the dust.

• Do not mix more mortar than you can use before it dries.

References

• Roll Rock Building Stone; How To Install Natural Thin Stone Veneer; 2003