Why use exterior wall insulation mesh with excellent alkali resistance?

In the construction of thin-plaster exterior wall insulation, the role of the fiberglass mesh is to prevent cracking of the insulation layer and damage from the mortar falling off. Therefore, the quality of the alkali-resistant fiberglass mesh is crucial to building insulation.

my country's exterior wall insulation technology started late, and the energy-saving effect and project quality are not ideal. Some projects suffer from poor insulation performance, surface cracking, peeling, water seepage, poor durability, poor fire resistance, and poor weathering and atmospheric stability. A major reason for these problems is the improper use of fiberglass mesh, such as excessively low basis weight, excessive elongation, mesh size that is too large or too small, insufficient application of the alkali-resistant coating, low alkali resistance retention, improper installation location, and cracking caused by gaps or non-overlapping of the mesh.

The current national standard for external wall insulation technology (JG149-2003) stipulates that the alkali-resistant tensile strength of the fiberglass mesh in both the warp and weft directions must not be less than 750 N/50 mm, and the alkali-resistant tensile strength retention rate must not be less than 50% per square meter of weight.

High-quality alkali-resistant mesh has three main indicators: alkali resistance, tensile strength, and tensile strain at break, with alkali resistance being the most important. Fiberglass mesh used in polystyrene board thin-plaster external wall insulation systems is required to have excellent alkali resistance because it is embedded in cement mortar.