How to Repair a Metal Mesh Foundation

Exposed Mesh Repair

• 1

  Put on a pair of work gloves and safety goggles to prevent injury during the repair process.

• 2

  Locate the damaged area of the foundation and examine the surface to determine the extent of the damage. Look for any exposed wire mesh within the damaged section. If mesh is present, you’ll need to cut through the slab and replace the damaged area with new concrete containing a new mesh layer. If there is no sign of mesh, you can proceed with an epoxy crack repair for small cracks less than 1/4 inch thick, or a mortar patch for wider cracks or breaks in the concrete.

• 3

  Place a chalk outline around the damaged section about 3 inches from the damaged area if you can see the wire mesh. Place the tip of a jackhammer on the line with the beveled side of the tip pointing toward the interior of the outlined area. Tile the jackhammer slightly toward you so that you’re cutting through the slab toward the damaged section. Start the jackhammer and break through the slab and mesh with the jackhammer, following the outline until you’ve broken an area that encompasses the damage.

• 4

  Turn off the jackhammer and switch to a sledgehammer. Break through the damaged slab with the sledge by striking the concrete from the outline toward the center until you have pieces of concrete you can haul away. Cut the mesh holding the pieces together with tin snips. Place the pieces into a wheelbarrow so that you can remove them from the repair area. Use a broom to sweep the debris from the area, and then haul off the debris.

• 5

  Cut a piece of wire mesh 1 inch smaller in diameter than the area of concrete you removed using a pair of tin snips. Mix a batch of concrete in a wheelbarrow using a hoe. Fill the hole halfway to the top with the concrete from the wheelbarrow using a spade. Place the sheet of cut mesh over the concrete layer and then fill the hole to the top. Use a trowel across the top of the concrete to smooth it out to the same level as the surrounding concrete. Allow the patch to cure for 21 days.

Spalled Surface Repair

• 6

  Remove any loose flakes of concrete from the foundation surface by sweeping the area clear. Cut any partially connected flakes away with a chisel and hammer. Chisel the flakes away at their bases using the chisel point, and then pull the flake from the surface.

• 7

  Clean the damaged area with a wire brush to remove debris, and then wash away any dirt with water. Dry the surface with a piece of cloth.

• 8

  Mix a batch of two-component epoxy gel adhesive with a wooden stir stick in a small bucket. Use a paintbrush to brush the damaged surface with the adhesive. Allow the adhesive to dry out until it’s sticky without being wet. The adhesive will help bind the patch material with the foundation surface.

• 9

  Use a drill with a grout mixing attachment to mix a bucketful of mortar patch material in a large bucket. Pour the patch material into the damaged area where you removed the flaking material. Fill the area to the level of the surrounding concrete, and then smooth the patch material with the flat of a steel trowel until it’s even with the surrounding foundation. Allow seven days curing time for the patching material before touching the foundation surface.

Large Crack Repair

• 10

  Repair large cracks in the foundation wider than 1/4 inch or greater than 1/2 inch in depth with no sign of wire mesh present, using a mortar patch. Clear out the crack prior to patching with a wire brush to remove debris and then wash the crack out with water. Remove any excess water from the area with a piece of cloth.

• 11

  Mix a small batch of two-component epoxy gel adhesive in a small bucket with a wooden stir stick. Brush the epoxy adhesive onto the sides of the crack with a paintbrush to create a binding layer between the patch material and the old concrete. Allow the adhesive to dry until it’s sticky but no longer wet to the touch.

• 12

  Mix a batch of mortar patch material in a large bucket with a drill containing a grout mixing attachment. Mix the mortar until it’s the consistency of thick cake batter.

• 13

  Fill the crack with the patch material using a trowel. Pack the crack tightly with the patch material, filling any small nooks that could otherwise form a void within the crack. Smooth the top of the crack with the flat of the trowel and allow the patch to cure for seven days before touching the repair area.

Small Crack Repair

• 14

  Clean out small cracks with the wire brush, and then wash them out with water. Dry the cracks with a piece of cloth.

• 15

  Mix two-component epoxy resin in a small bucket with a wooden stir stick.

• 16

  Fill the crack with the resin using a putty knife. Stuff the crack to the level of the surrounding surface and then scrape over the patch with the knife to level the resin out. Allow the resin to dry for 48 hours before touching the repair area.