Cracks and cracks are the most common quality problems in construction projects. It has an impact on building waterproofing, building appearance, and the overall quality of construction projects. It is also the direct cause of building leakage. Cracks are mostly reflected on the base layer. Because the base layer has cracks. The same cracks will inevitably occur with exterior wall putty.
These cracks are mainly caused by the subsidence of the foundation. The change of the wall structure. And the instability of the base. Straight line or oblique line, or irregular straight line or oblique line, regardless of the size or number of gaps. Basically has nothing to do with putty.
The outer wall putty is prone to irregular cracks, which is mainly related to the poor adhesion of the outer wall putty, poor crack resistance, and improper treatment of the base layer interface. If the cracking phenomenon caused is more serious, there may be the consequences of cracking first, then hollowing, and then falling off. Years of research and experiments have shown that no matter whether there are cracks or cracks in the building, it is basically a crack to the end. Even with highly elastic materials, it is difficult to completely repair.
The processing of the grassroots and the grassroots interface has the following contents.
1. Stability of the grassroots
The base layer should be carefully checked and confirmed before construction. Check the flatness, strength and water absorption of the base layer. Whether there is any phenomenon of pulverization, looseness and alkali return in the base layer. Whether there are obvious cracks and cracks (can be checked by pouring water on the wall). Whether the base has been stabilized. If the base layer fails to meet the construction requirements of exterior wall putty, corresponding technical treatment should be done first. If the base meets the construction requirements for exterior wall putty, exterior wall putty construction can be carried out.
2. Strength of the base layer must be greater than that of the exterior wall putty.
Bonding theory and practice by material. If the strength of the base layer of the wall is lower than that of the putty on the exterior wall, the putty on the exterior wall is prone to “rooting”, hollowing, and falling off. These problems will not occur if the base strength is greater than that of the exterior wall putty.
3. Strict handling of the interface.
First remove floating ash and oil stains (including release agent), fill and scratch the cracks in the base layer, and remove bulges. If there is obvious unevenness in the base, use anti-crack mortar to level it first. If the base layer is particularly dry, has strong water absorption, and the ambient climate is also very dry, it will affect the adhesion and strength of the putty on the exterior wall and the base layer. Therefore, it is recommended to wet the base of the wall with water before construction, and then carry out the construction of putty on the exterior wall. If conditions permit, 2-3 days after construction, it can be sprayed with water for 1-2 times for maintenance, and the anti-cracking effect and strength will be better.
Summary: Exterior wall putty is the most important part of the exterior wall decoration project. Once there is a problem with the putty. No matter how good the paint is on the exterior wall, it will not achieve the desired effect. The product quality of exterior wall putty lies in the quality of cement, the selection and application of fillers and polymer additives.
In terms of construction, construction personnel are familiar with and understand the properties of materials. The influence of base, interface and climate environment on the performance of exterior wall putty. The level of construction technology, the meticulous workmanship and excellence in the construction process, etc. These are all very important factors for the construction quality of high-quality building exterior wall putty.