Improper practice
When the ceiling elevation is the same as the beam bottom elevation, gypsum board will not pass through the beam bottom, which will cause the interface between gypsum board and beam bottom. This interface will crack due to temperature difference and expansion deformation of different materials during use.
Correct approach
When the ceiling elevation is the same as the beam bottom elevation, gypsum board must pass through the beam bottom. The advantage of this is that there is no interface, which will effectively reduce joints and prevent cracks. In addition, gypsum board should pass through the lower part and side of the beam when dealing with the ceiling elevation and the horizontal hole of the beam. Leave the seam on the edge, so that there is no bottom plate for the seam, which will reduce cracks and maintenance rate.
Improper practice
The gypsum board in the corner of the ceiling gypsum board is sealed without L whole board, which is easy to shrink and produce cracks. When the wooden keel ceiling is sealed with gypsum board in the corner, if the whole board construction is not adopted, the gypsum board at the bottom will have joints in the corner. Due to the interface of the base material, the material is easy to shrink and cracks will occur.
Correct approach
I-shaped gypsum board is sealed at the corner of wooden keel of ceiling to prevent cracks. When the wooden keel ceiling is sealed with gypsum board at the corner, L-shaped whole plate construction is adopted. The gypsum board at the bottom is an L-shaped whole board in the corner. The cracks can be effectively controlled by leaving cracks on both sides of the ceiling, making it into a figure of eight, and then filling the cracks with Lafarge or gypsum powder.