Should rebar be inserted into rock to hold footings?
If you don’t pin your footings to the rock with rebar even a strong wind could knock over the structure. You need concrete footings underneath a foundation to provide a base that will distribute the weight of whatever is sitting on top and, on rock, you need rebar to keep everything from moving or sliding off. Drill two or three 8″-dia. holes for each footing, about 1′ deep into the rock. Put lengths of 6″ rebar into each hole and set in place with epoxy anchoring adhesive. Make sure the hole is clean, since any dust will interfere with how the cement grout holds. The concrete, which will make up your footing, then gets poured into a form around the rebar.
Related Story An ingenious DIY solution to lighting rocky pathways
Related Story 6 speciality drill bits that you need in your tool box