How to Repair Small Dents in Wallboard:

Tool and Material Checklist:

Sandpaper (Course & Fine), Joint compound, Keyhole saw, Good grade of adhesive, Wallboard tape, Small pieces of wallboard, Hammer, Sandpaper block, Scraper, Putty knife, Hand saw, Heavy cord, Short sections of 2x4's, Small nails

Objects shoved against wallboard sometimes make dents or scratches in the surface. These are not actual breaks. They are merely indentations that can be easily repaired with a minimum of effort.

Step 1 in repairing a dented or scratch wallboard is to sand the surface thoroughly. This sanding roughens the surface and provides a good base for the joint filler compound.

Use coarse sandpaper and a good sandpaper block. If you have a lot of patch work to do, a power sander may be needed.

Fill the dent with a good grade of joint compound. Use a 3" or 4" spreader for applying the joint compound. Spread it evenly and press it firmly into the dented area.

If the dents are extremely large, it may be necessary to let the compound dry overnight and then apply a second coat.

When material is completely dry, sand the area and prime it for a coat of paint or whatever finish you prefer to use.

Be sure to remove any high or low spots in the patched area. Use a fine sandpaper for the finish job.

2. Patching Cracks in Wallboard

Various types of patching powders and compounds are available for patching wallboard. Some are powder, others are offered in paste form.

Regardless of what type of patching compound you use, read the manufacturer's instructions carefully and follow each step as suggested. Some patching plaster dries quickly while other types of plaster require longer periods to dry.

Be sure the cracked area which is to be patched is completely clean and dry. Remove all dirt from the area around the crack. Clean out all cracks so the patching plaster can be inserted in them.

Apply the patching plaster with a wide and flexible putty knife. Apply the patching plaster by working across the crack with strokes in both directions. This tends to work the patching plaster into the crack better than strokes in one direction.

Force the patching material into the crack with strong, firm strokes. Examine the crack after each stroke. If more material is required, apply it and force it into the crack at all points.

Apply enough pressure to the knife to bend it as you draw it along the cracked area. Repeat the passes along the crack as often as necessary to force the material well into the cracked surface.

Now remove any surplus patching material by using the putty knife as a scraper. Move it along the cracked area gently to scrape away all the surplus patching material which was applied by the double strokes in each direction.

It sometimes helps to dip the putty knife into water and make one final pass along the repaired area. You can then apply a finish, touch-up application to finish the job.

After the patched area has dried completely, it can be sanded and primed or painted as you desire.

3. Patching Small Holes in Wallboard

Holes in wallboard up to 18" in diameter can be patched and repaired in a way that makes them totally inconspicuous.

Smaller holes, less than 12" in diameter can be repaired without a supporting brace across the back. In such cases, cut out the hole with a keyhole to provide even edges along all sides.

Now cut a patching piece of wallboard about 2" larger that the hole which is to be repaired. Punch or drill 2 small holes through this piece of board and tie a stick to the board as illustrated. Allow for about 8" between the board and the stick.

Apply a smooth coat of some good grade of adhesive all around the edge of the piece of patching material.

Insert the piece of patching board through the hole and position it so the adhesive fits firmly against the solid area around the hole.

Now turn the stick clockwise to twist the string and increase pressure against the patch board at the rear of the hole. When the string has been thoroughly tightened, it will hold the board firmly into place until the adhesive dries.

Give the adhesive a little time to dry. Then begin to fill in the area to be patched with a good grade of patching plaster. Leave the stick and the string in position during this patching process.

It may be necessary to apply 2 or 3 layers of patching plaster to build up the patched area adequately. Let on e layer dry before applying another.

Remove the stick and string just before the material dries. Smooth out the area where the string was drawn through the plaster then let the complete patch dry thoroughly.

When the patched area is completely dry, sand off all high spots and apply a prime coat for paint of other coating.

It is best to use a fine grade of sandpaper and a sanding block when doing this finish sanding work.

4. Patching Large Holes in Wallboard

Larger holes in wallboard will require some type of supporting brace when a patch is inserted.

A short piece of 2x4 cut to the proper length can provide such a supporting brace for patching a large hole in plasterboard.

Cut 2 pieces of 2x4 to a length approximately 8" longer than the distance across the hole.

Apply some good grade of cement to 1 piece of the 2x4 then insert it through the hole and tie it to another piece of 2x4 which is held parallel to it but in front of the wallboard.

Allow the 2 pieces of 2x4 to remain tied in this position until the cement dries and holds the back piece of 2x4 firmly to the back of the wallboard. Most cements will require about a one hour drying time.

Now remove the supporting piece of 2x4 in front of the wallboard by untying the string. The cement will hold the back piece of 2x4 firmly in position to provide a supporting brace for the wall patch.

Now cut a patch block to fit exactly into the sawed out area which is to be patched. The block will have to be slightly smaller than the hole itself, but it should be cut to fit as tightly as possible.

Now use a firm putty knife or patching spatula to apply joint compound all around the patch board.

Work the patch compound thoroughly into all cracks then scrape away any surplus material and let the patched area completely dry.

When the area has completely dried, use a regular sanding block and a piece of fine sandpaper to sand away any high areas on the patched surface.

When the area has been thoroughly sanded and smoothed, a prime coat can be applied to get the wall ready for painting.

5. Repairing Loose Tape on Wallboard

Sometimes tape will pop loose at the joints in wallboard. This can be caused by shrinkage in the wallboard material or by a settling of the building.

Check all joints carefully and remove any loose tape. Run your fingers along the joints. If you feel air bubbles, strip all loose tape away.

Pull any loose tape off carefully. Try to avoid removing sections of the joint compound and wallboard core when taking the old tape off the wall.

Now sand the area where the tape was removed very carefully. It is important that you take time to sand this area properly. If you do not do so, sumps may appear when the new tape is applied.

When the area has been completely sanded, apply new tape, with a regular putty knife and a good grade of tape compound.