Fiberglass Mesh for ETICS: The Essential Reinforcement for a Long-Lasting External Insulation System

Alkali-resistant fiberglass reinforcing mesh is one of the key components of an External Thermal Insulation Composite System (ETICS). Embedded within the base coat layer, it performs the essential structural function of evenly distributing surface stresses and helps prevent the formation of hairline cracks and fissures over time.

A high-quality reinforcing mesh is not simply an accessory, but an indispensable element for ensuring the durability, mechanical strength, and long-term reliability of the entire insulation system.

Technical Specifications

• Roll length: 50 m (±1%)

• Width: 100 cm (±1%)

• Mesh size: 4.5 (±1) mm × 4.5 (±1) mm

• Colour: White

• Weight: 158 g/m² (±5%)

• Organic content: 20 (±4)%

• Tensile strength: 35 N/mm / 40 N/mm

• Elongation: 4.5%

• Fire reaction class: F

• Certification: ETAG 004

Packaging

The rolls are individually wrapped with heat-shrink film

Storage

Store rolls in dry conditions. Recommended storage temperature: from -10°C to +40°C.

Why Is Reinforcing Mesh Important in an External Insulation System?

An external insulation system is continuously subjected to stresses caused by:

• Daily and seasonal temperature fluctuations;

• Expansion and contraction of building materials;

• Natural structural movements of the building;

• Shrinkage of cement-based mortars;

• Accidental impacts;

• Wind loads and weather exposure.

The fiberglass mesh embedded in the reinforced base coat absorbs and distributes these stresses across the entire surface, reducing the risk of cracking, fissures, and detachment of the finishing render.

Alkali-Resistant Fiberglass Mesh: Protection Against Degradation

Standard fiberglass can deteriorate over time when exposed to the highly alkaline environment of cement-based mortars and base coats.

For this reason, ETICS reinforcing meshes are treated with special alkali-resistant coatings that preserve their mechanical properties even after years of service. This protection enables the mesh to maintain its reinforcing function and ensure the long-term stability of the insulation system.

ETAG 004 Certification: Why Is It Important?

ETAG 004 (European Technical Approval Guideline 004) was the historic European guideline developed by the European Organisation for Technical Approvals (EOTA) for the technical assessment of External Thermal Insulation Composite Systems (ETICS).

This guideline established the performance requirements for all system components, including reinforcing mesh, evaluating:

• Mechanical strength;

• Behaviour after accelerated ageing;

• Alkali resistance;

• Long-term durability;

• Compatibility with ETICS systems.

Although ETAG 004 has now been replaced by the more recent EAD 040083-00-0404 for ETICS kit assessments, compliance with ETAG 004 remains an important quality benchmark for reinforcing meshes and many ETICS components.

Benefits of ETAG 004-Compliant Reinforcing Mesh

Choosing a mesh that complies with ETAG 004 requirements means benefiting from:

• High tensile strength;

• Excellent dimensional stability;

• Superior alkali resistance;

• Improved crack control;

• Enhanced durability of the insulation system;

• Performance verified through recognised European laboratory testing.

Reinforcing Mesh Improves Impact Resistance

In addition to reducing the risk of cracking, reinforcing mesh increases the surface resistance of the insulation system against accidental impacts.

This is particularly important in lower façade areas, high-traffic zones, and buildings exposed to greater-than-normal mechanical stresses. In such situations, additional reinforcement or double mesh layers may be specified in critical areas.

Correct Installation of Reinforcing Mesh in ETICS Systems

To achieve the expected performance of the insulation system, the mesh must be fully embedded within the reinforced base coat layer, avoiding placement too close to the surface or directly against the insulation board.

It is also essential to provide:

• Mesh overlaps of at least 10 cm;

• Diagonal reinforcement at window and door corners;

• Proper coverage with base coat mortar;

• Continuous reinforcement across the entire façade surface.

Careful installation allows the mesh to perform at its full potential and contributes to a stronger, more durable façade.