SIKA Sikasil® SG-500 Silicone Sealant

SIKA Sikasil® SG-500 silicone sealant: structural glazing and facade bonding

Sikasil® SG-500 is a high-performance structural silicone sealant designed for glazing bonding and curtain wall assembly.

It provides a durable bond between glass, aluminum, and facade materials, even under significant mechanical and climatic stress.

Formulated by SIKA, this product meets the requirements of the most technical structural applications.

What is Sikasil® SG-500? Overview and composition

A two-part structural silicone with neutral curing

Sikasil® SG-500 is a two-part structural silicone sealant developed by Sika. It is specifically formulated for structural glazing bonding and the assembly of facade elements.

Its neutral curing properties ensure high adhesion to glass, anodized aluminum, and stainless steel, generally without the need for a primer.

As a two-part system, it cures through a chemical reaction between the base and the hardener. This ensures a consistent, controlled cure regardless of atmospheric humidity levels.

Once cured, Sikasil® SG-500 forms a flexible and resistant elastomer capable of absorbing differential movements between the assembled materials. This is a key factor for curtain wall and facade applications.

It meets the requirements of ETAG 002 (European Technical Approval Guideline for structural glazing), making it a reliable choice for projects subject to strict standards.

At Dagobert Industrie, we offer this product to building, aluminum joinery, and facade professionals looking for a certified structural silicone that is proven in the field.

Technical properties and performance of Sikasil® SG-500

Mechanical, thermal, and UV resistance: what the technical data sheet guarantees

Sikasil® SG-500 is a two-part silicone sealant, designed specifically for structural glazing and facade bonding.

Its tensile strength reaches approximately 0.6 MPa, with an elongation at break greater than 150%. It withstands significant deformations without peeling or cracking.

Thermally, the product remains functional between -40 °C and +150 °C in continuous service. This range covers almost all climatic exposures for facades, including south-facing glazing.

UV stability is one of the SG-500's major assets. Unlike some acrylic or polyurethane sealants, it does not yellow or degrade under prolonged sun exposure. The black color remains stable over time.

It also exhibits excellent resistance to atmospheric agents: rain, humidity, and hygrometric variations. Ideal for curtain wall applications and glass-to-metal assemblies exposed to the elements.

Property	Sikasil® SG-500	Sikasil® SG-20	Dow 995
Type	Structural 2C Silicone	Structural 2C Silicone	Structural 1C Silicone
Tensile strength	~0.6 MPa	~0.8 MPa	~0.7 MPa
Thermal range	-40 °C / +150 °C	-40 °C / +150 °C	-54 °C / +149 °C
UV stability	Excellent	Excellent	Excellent
Curtain wall use	Yes	Yes	Yes

Areas of application: curtain walls, glazing, and structural assemblies

Sikasil® SG-500 is designed for demanding structural bonding applications where mechanical strength and durability are non-negotiable.

Its primary field is curtain walls and concealed frame facades. It bonds glass, aluminum, stainless steel, or composite panels directly to the load-bearing structure, without visible screws or mechanical fasteners.

It is also suitable for structural glazing in the workshop or on-site, for assemblies subject to wind, thermal expansion, or vibration stresses.

Typical applications covered include:

• Aluminum-framed curtain walls
• Structural glazing (SSG) mono and two-component
• Glass/metal and glass/glass assemblies
• Composite aluminum or steel facade panels
• Glass roofs, atriums, and skylights
• Bonding joints subject to dynamic loads

Product	Manufacturer	Type	Main use	Structural strength
Sikasil® SG-500	Sika	2-component silicone	Curtain walls, SSG	High
Sikasil® SG-20	Sika	2-component silicone	Industrial SSG, series production	Very high
DC 995	Dow	1-component silicone	Curtain walls, SSG	High
Ottoseal® S 70	Otto Chemie	1-component silicone	Glazing, joinery	Medium

The SG-500 is distinguished by its ETAG 002 certification, the European benchmark for structural sealant glazing. This is a decisive criterion for projects subject to strict regulatory requirements.

Sikasil® SG-500 compared to other structural silicones: comparison table

Comparison with Sikasil® SG-20, Dow 993, and other structural silicones

The market for structural silicones for facades and glazing offers several key references. Here is how Sikasil® SG-500 positions itself against its main competitors.

Product	Manufacturer	Components	Elastic modulus	UV resistance	Main application
Sikasil® SG-500	Sika	2 components	High	Excellent	Structural facade bonding, exterior glazing
Sikasil® SG-20	Sika	1 component	Medium	Very good	Interior structural bonding, small surfaces
Dow 993	Dow	2 components	High	Excellent	Structural curtain wall bonding
Dow 995	Dow	1 component	Medium-high	Very good	Structural glazing, facade joints

The two-component Sikasil® SG-500 is distinguished by its rapid and controlled curing, independent of ambient humidity. This is a decisive advantage in workshop or industrial settings.

The single-component Sikasil® SG-20 is easier to implement but cures through moisture, making it less predictable on large surfaces or in dry environments.

Compared to Dow 993, the SG-500 offers comparable mechanical performance. The choice often depends on the available applicator system and design office specifications.

At Dagobert Industrie, we recommend Sikasil® SG-500 for any project requiring certified structural bonding with high requirements for durability and long-term mechanical strength.

Implementation tips and precautions

Before any application, surfaces must be clean, dry, and degreased. Use a suitable primer (Sika Primer-215 or equivalent) on porous or difficult substrates.

Apply Sikasil® SG-500 at a temperature between +5 °C and +40 °C. Below this range, curing slows down significantly and adhesion may be compromised.

The product comes in two components (base + hardener). The mixture must be homogeneous before application: strictly follow the mixing ratio indicated in the Sika technical data sheet.

The open time is limited: position the glass elements quickly after application. Any late adjustment impairs the adhesion and mechanical integrity of the joint.

During curing, protect the assembly from any mechanical stress (vibration, shock, weight). The handling time varies according to temperature and bead thickness.

Essential precautions:

• Wear protective gloves and goggles during handling
• Ensure sufficient room ventilation during application
• Do not apply to damp or frozen surfaces
• Avoid any contact of the uncured product with mucous membranes
• Store away from heat and moisture, between +5 °C and +25 °C

If in doubt about compatibility with a specific substrate (anodized aluminum, treated glass, composite...), always perform a preliminary adhesion test before any series production.

FAQ - Sikasil® SG-500

1. Is Sikasil® SG-500 approved for structural facades?

Yes. Sikasil® SG-500 is certified according to ETAG 002, the European technical guideline for structural glazing.

It meets the requirements of curtain walls and glass assemblies subject to significant mechanical loads. It is a validated product for use in demanding professional environments.

2. What is the difference between a structural silicone sealant and a standard silicone?

A standard silicone is used for sealing. It fills joints but is not designed to transmit mechanical forces.

A structural sealant like Sikasil® SG-500 provides both sealing and structural bonding. It holds the glazing in place permanently, even under wind, thermal expansion, or vibration.

3. Can Sikasil® SG-500 be applied to all types of glazing?

It is compatible with monolithic, laminated, and insulating glass (double or triple glazing). It also adheres to aluminum, stainless steel, and certain treated glass substrates.

Verification of compatibility with Sika primers is recommended depending on the substrate. At Dagobert Industrie, we provide the Sika primers adapted to each configuration.

4. What is the curing time of Sikasil® SG-500?

Complete curing depends on temperature and ambient humidity. Under standard conditions (23 °C / 50% RH), allow about 3 to 4 weeks for full depth curing.

Surface curing occurs much earlier, generally within a few hours. The joint should not be loaded before complete curing.

5. Is Sikasil® SG-500 compatible with the surface treatments of anodized aluminum?

Yes, Sikasil® SG-500 is formulated to adhere to anodized and lacquered aluminum, widely used in facade joinery.

A preliminary adhesion test is still recommended, especially on colored anodizations or atypical lacquers. Using Sika Primer-190 optimizes adhesion to these surfaces.