Filling Holes and Cracks in Interior Walls
Holes, cracks, and dents in wall surfaces are unsightly, but not overly difficult to repair. How the repair is made will depend on the wall material. Use this easy to follow guide to repair the most common interior wall surfaces.
Plasterboard or Wallboard
Cracks and Small Holes
Fill cracks and small holes in plasterboard or wallboard by first digging out any loose pieces of material. Fill the crack or hole with spackling or joint compound. Smooth with a wide putty knife, and let dry. If ridges remain or the patch is obvious, sand to blend the area with fine-grit sandpaper.
To repair peeling joint tape, first remove the old section of tape. Cut away with a sharp utility knife. Use the knife to score the compound along the edges of the tape. Try not to pull off large chunks of the compound along the repair edges.
Cut a new section of joint tape and apply to the repair area. Smooth new joint compound over the replaced tape, overlapping the adjacent area slightly. Let the compound dry for 24 hours and apply a second coat of compound. Let the second coat dry completely, then sand with fine-grit paper to blend.
To repair larger holes in plasterboard or wallboard, first cut the hole to a rectangular shape larger than the damaged area. Using construction adhesive, glue a section of 1" x 2" wood to the back side of the hole. The wood should be about 4 inches longer than the width of the rectangle. Secure the wood with drywall screws from the front side of the hole.
Cut a piece of board to patch the hole that is approximately 1/8 inch smaller than the hole. Cover all edges of the patch with joint compound and press the patch-board into place. Cover the entire patch and over the edges with joint compound. Smooth to blend. Sand when dry with fine sandpaper.
Fine cracks on plastered walls should be widened slightly to allow for better adhesion of the filler. Use a screwdriver to widen cracks and clean away loose plaster with a firm-bristled brush. Cracks wider than 1/4 inch should be undercut for best adhesion (taper bottom edge at an angle wider than the top of the crack at the wall's surface).
Fill the widened and cleaned crack with spackling. Smooth with a putty knife. Let the spackling dry according to package directions, then sand with fine sandpaper before finishing.
To repair small holes in plaster, first clean away all broken pieces of plaster. Using water, wet the edges of the small hole. Apply a plaster bond product to the edges.
Fill the hole with a plaster patching product. Work from the outside edge into the center until the entire hole is filled halfway to the surface. Score small grooves in the plaster with the putty knife so the second layer of patch adheres to the first. Allow the plaster to dry for 24 hours.
Wet the first layer of plaster patch with water just until damp and apply a second coat of patching plaster. Smooth the surface with the putty knife. Sand when dry.
For larger holes that will not fill completely, a layer of mesh wire needs to be applied before the patch.
Cut away broken plaster pieces so there is a solid frame of sturdy plaster, undercutting edges as described above. Cut a piece of mesh wire larger than the hole. Work a piece of wire through the center of the mesh and gently ease the wire through the hole. Pull the looped wire to hold the mesh patch firmly against the back of the wall. Twist the center wire around a dowel held against the front of the wall to hold the mesh in place.
Fill the hole as previously described. Be sure the plaster works into the wire mesh. With the first layer of patch dry, cut the wire and dowel away. Finish filling the hole.
Repair dents, holes, and missing knots in wood wall surfaces by first filling with wood filler. Let the area dry according to package directions, and sand to a smooth finish. Wood filler can be sanded, painted, or stained along with the rest of the wood.
With these tips, any small or medium size wall imperfection can be filled and smoothed to inconspicuously patch wall damage. With paint or finish applied, no one will ever know the damage was there.