Causes and prevention measures of cracking of wall putty layer

Putty layer cracking is a common defect in wall decoration, which seriously affects the appearance and durability. To effectively avoid cracking problems, it is necessary to accurately identify the causes and take targeted measures. Now analyze from two dimensions: materials and construction:

1. Core causes of cracking of putty layer

Material factors:

Shrinkage stress: Shrinkage stress is generated during the drying process of putty.

Temperature stress: Changes in ambient temperature cause thermal expansion and contraction.

Material defects: Use putty or inferior materials with mismatched bonding strength; improper proportioning leads to unstable performance.

Construction factors:

Base defects: The base surface is unclean, loose or the old putty layer remains, resulting in failure of bonding between the new and old layers.

Insufficient drying: The previous putty is not fully cured before covering the next layer.

Over-thickness: The thickness of a single layer of putty exceeds the standard, and the drying rate inside and outside is different.

Structural deformation: The wall is displaced by load or settlement, causing structural cracks.

2. Solution for cracking

Complete eradication: For cracked areas, it is recommended to completely eradicate until the base is stable.

Flexible transition (limited to minor cracks): For minor cracks, flexible putty can be used as the first repair layer, and then the standard process is used for subsequent construction.

Standardized construction:

Strictly control the thickness of a single layer (usually ≤2mm).

Ensure that each layer of putty is completely dry (the interval time depends on the environment, usually >4 hours) before subsequent operations.

3. Key preventive measures

Base reinforcement treatment:

Completely remove floating dust, oil stains and loose old layers.

Repair structural cracks and holes.

Apply qualified interface agent: Enhance the bonding between new and old layers and buffer stress.

Scientific selection of materials:

Select high-quality putty with suitable bonding strength and excellent crack resistance.

Strictly mix according to the manufacturer's ratio to ensure material homogeneity.

Construction process control:

Layered thin batches: Follow the principle of "thin batches and multiple times", and the thickness of a single layer does not exceed the product requirements.

Sufficient drying: Ensure that each process is completely dry before continuing.

Environmental management: Avoid construction in high temperature, high humidity or over-ventilated environments.

Conclusion

Systematic prevention and control is required to cure putty cracking: strictly control material quality, accurately treat the base layer, and standardize construction technology. Through scientific material selection and refined management, the risk of cracking can be significantly reduced, ensuring the long-term beauty and stability of the finishing layer.