When the foam dries, the excess can be cut.

In the presence of medium cracks, on the walls or ceiling, they are sealed with cement mortar, and then putty, and mixtures from gypsum are also suitable. If the cracks are large, then you can fill with foam special fillers. Foam increases in its volume, so keep in mind that the level of foam should be below the edge of the crack. When the foam dries, the excess can be cut. Put a cement mortar or plaster from gypsum on the foam. We glue a reinforced special tape and a crack hubby. For greater strength, you can add a primer to the solution and mix. This method is also suitable for sealing cracks at the junction of panels or in the corners.