I. Reasons for detachment of exterior wall bricks
1、The expansion joints between tiles have not been properly reserved.
During the installation of exterior wall tiles, if the appropriate expansion joints are not properly provided, the exterior wall tiles will not have sufficient space for expansion and contraction. This can lead to the tiles being squeezed and detached in situations with significant temperature changes.
2、The thickness of the mortar adhesive applied to the wall is uneven.
Uneven wall substrate and an improperly leveled leveling layer result in uneven mortar thickness when attaching bricks, leading to inconsistent shrinkage and potential brick detachment.
3、When adhering exterior wall bricks, the leveling layer becomes excessively dry.
During the hardening of cement mortar, cement undergoes hydration, which requires sufficient water. If there is not enough water, the cement cannot complete the hydration process, which cannot guarantee the strength of the cement mortar. As a result, the exterior wall bricks may detach due to insufficient bonding strength.
Two. What to do when exterior wall bricks are detaching?
1、only the mortar under the tiles is detached.
At this stage, all the mortar on the exterior wall bricks can be completely removed. Then, add an appropriate amount of cement to the 107 adhesive and mix it into a paste. Apply a thin layer of this mixture to the back of the tiles, and then attach the tiles to the previously pasted wall. The tiles will quickly adhere.
2、Ceramic tiles and mortar are both detaching.
First, create small indentations in the areas where the tiles are detached. Then, re-install the tiles using a mortar mixed with 107 adhesive, firmly pressing the tiles against the substrate. once the mortar has partially hardened, the tiles will be securely in place.
III. How to Prevent Brick Detachment on Exterior Walls
When laying exterior bricks, it is essential to apply the cement mortar evenly. The application time should not be excessive to prevent premature drying and hardening, which can lead to separation between the mortar layer and the substrate, resulting in bulging and detachment.
Mix the mortar according to the specified ratio, and do not add any extra water. The thickness of the mortar should be controlled between 2-3 centimeters.
When laying exterior wall bricks, the back surface should be cleaned of loose debris and dampened to ensure good adhesion. When laying bricks, apply even pressure to all four corners to ensure they are flush with the mortar bed and elevated 2-3 centimeters above the string line. Then, use a wooden hammer or rubber hammer to tap the bricks into place.
After laying a section of exterior wall bricks, lay the remaining bricks in a sequential manner, either to the sides or towards the rear. If any depressions are observed, lift the exterior wall bricks and level the substrate with mortar before re-laying.