Quck answer
Concrete ceilings can sustain non-structural damage over time due to various factors like water leakage, cracks, or wear and tear. To repair such damage, follow these steps:
1. Clean the damaged area by removing loose debris and dirt.
2. Use a wire brush to remove any loose or chipped concrete.
3. Fill the cracks with epoxy or a suitable concrete patching compound, following the manufacturer’s instructions.
4. Smooth the patched area using a trowel or putty knife, ensuring it is level with the surrounding ceiling.
5. Allow the patch to dry completely before applying a coat of concrete sealer or paint to match the rest of the ceiling.
6. Regularly inspect and maintain the ceiling to prevent further damage.
Cracks or damage in concrete ceilings indicate a problem. There is a failure in either the support structure or the concrete itself. The shifting of the foundation due to movement in the ground or soil settling can cause the walls to shift and concrete ceilings to crack. Ordinary cement cannot fix this issue because it shrinks when it dries. However, new materials have been developed that are strong, durable, and expand as they dry. By doing some preparation work, you can create a long-lasting and permanent repair.
Step 1
Thoroughly clean the ceiling with soap and water, and then use a cleaning solvent to remove grease and oils from the surface that needs repair. Make sure to dry the surface completely.
Step 2
Using a hammer and chisel, work around the edges of the crack or hole, undercutting and widening the crack behind the surface edges. This will create a flat-topped inverted “V” shape, similar to a dovetail joint in a dresser drawer corner. On a ceiling, the wider part of the “V” will be above the surface of the crack, so it will be right side up in relation to gravity. Remember, you are working upside down on a ceiling. Avoid cutting the crack in a “V” shape with the narrow end away from the surface, as the expanding repair compound will push itself out of the crack. The dovetail shape will ensure that the repair material is securely pushed into the crack.
Step 3
Follow the manufacturer’s instructions to mix an epoxy-based concrete repair compound. Use a type that bonds more slowly, as this can be challenging in a ceiling repair. You will need to provide some backing to the repair. The dovetail shape of the crack will help hold the repair compound in place, but make sure to inject plenty of compound into the crack to achieve a good seal throughout its depth.
Step 4
Use a putty knife to smooth the top of the repair compound, pressing it well into the crack. Add more compound if it further squeezes into the crack. Do not skimp on the repair. If some compound squeezes all the way through the crack into the attic or onto the roof, it will actually provide better support for the repair.
Step 5
While the repair compound cures, cover it with strips of cardboard and secure them in place with duct tape. You can even tape directly over the compound. Once it has set, the tape will peel off easily. Allow the compound to fully set and cure.
Step 6
Use sandpaper, specifically designed for metal or concrete, to sand over the top of the repair and blend it into the ceiling. If the repair is in a finished space, recoat or paint the ceiling where the repair was done. The repair compound may have pushed up slightly, so you will need a coarse-grade sandpaper to smooth the surface for painting or sealing. Apply paint or sealant. To achieve an invisible repair, you may need to redo the entire ceiling section where the repair was made.
