Some useful tips to repair cracks in plaster walls

Cracks in plaster walls are normally occurred due to various factors like settlement, vibration or atmospheric conditions and in some cases for defective construction.

To repair cracks, the following items will be required :-

a. Blade for widening of cracks
b. Patching material usually putty
c. Painting brush
d. Paint scrapper
e. Flexible putty knife for filling
f. Fine grade sandpaper


1. With the help of blade or putty knife, broaden and undercut opening to arrange grip for filler. If filler material is applied in very small quantity then there will be no tough bonding and too much quantity is not also recommended. In second option, opt for plastering initially.

2. Arrange the patching material to fill the crack; blend it with a solid, buttery consistency for quick application. Ready-made putty is accessible almost everywhere and it should be blended with water.

3. Apply a brush to moisten the surface or spray to the full depth of the unsealed crack. Ensure water arrives at the far end of crack. The surface should be moistened perfectly to make the bond better.

4. The patching material alias putty should be applied through a flexible putty knife to fill the opening totally. Finally, take away surplus putty and level it on the wall by a paint scrapper.

5. A fine grade sand paper should be applied to smooth the patch surface. The adjacent surface should also be leveled. If gap still exists among crack layer and adjacent, then apply second filling coat to keep it dry. As soon as, it becomes dry, again use sand paper. Dust the surface and check for any divergences.

6. As soon as repaired patch gets dried, use prime coat over the filled-in crack and surface adjacent area. It will conceal the repaired area and provides a fine smooth finishing.

7. To patch a big crack, then undercut it, take away all the loose plaster and moisten the surface like equivalent to small crack.

8. Blend a batch of plaster and fill the cavity. Keep it dry for 24hours. Shrinkage may take place throughout drying.

9. If shrinkage happens, moisten again the patch area and fill cavity with fresh filler. Let it gets dry. Sand smooth and finally use prime coat.

Some useful tips to repair cracks in plaster walls