Construction sealant selection is not simply a matter of choosing silicone, MS polymer, or polyurethane. The correct sealant depends on the substrate, joint movement, exposure conditions, required adhesion, and whether the joint is intended for weatherproofing, glazing, or structural bonding.

For contractors, facade engineers, distributors, and specifiers, three questions should come first:

1. What materials are being sealed or bonded?
2. How much movement will the joint experience?
3. Is the sealant required for weatherproofing, glazing, or structural bonding?

These questions become especially important in facade applications involving glass, concrete, and aluminum panels. A sealant that performs well on one substrate may not be appropriate for another.

This guide provides a practical construction sealant selection framework and a substrate-based decision matrix for choosing the right facade sealant.

1. Construction Sealant Selection: The Five Factors That Matter

Before comparing products, evaluate the joint using five technical factors.

Selection Factor	What to Check	Why It Matters
Substrate	Glass, concrete, aluminum, stone, PVC, etc.	Determines adhesion and compatibility
Joint Movement	±20%, ±25%, ±35%, ±50%	Determines required elasticity
Exposure	UV, rain, freeze-thaw, humidity, heat	Determines weathering requirements
Joint Function	Weatherproofing, glazing, structural bonding	Determines sealant technology
Aesthetic Requirements	Clear, translucent, color-matched, paintable	Affects silicone vs. MS polymer selection

The key principle is simple:

Do not select a sealant by product name alone. Select it by substrate + movement + environment + function.

For example, a curtain wall joint exposed to strong UV radiation and large thermal movement requires a different solution from an interior concrete joint.

2. Silicone vs. MS Polymer: Which Construction Sealant Should You Choose?

Silicone remains an important technology for exterior weatherproofing and structural glazing. MS polymer, meanwhile, can offer advantages where paintability, low migration, or primerless adhesion are priorities.

INGADA’s product portfolio describes MS polymer as combining silicone-like weather resistance with polyurethane-like adhesion while providing paintability, zero migration, solvent-free formulation, and high elasticity.

Technology	Main Advantages	Typical Limitation	Typical Construction Use
Silicone	Excellent UV and weathering resistance	Generally not paintable; formulation-specific migration/staining considerations	Curtain walls, glazing, exterior joints
MS Polymer	Paintable, flexible, solvent-free, low migration	May have higher material cost than standard silicone	Expansion joints, prefab structures, facade joints
Polyurethane	Strong adhesion and structural strength	Lower UV resistance; may require primer depending on application	Construction joints and specialized bonding

For facade projects, the right choice is therefore determined by joint function, not simply by chemistry.

3. Construction Sealant Selection Decision Tree

A practical decision tree for common facade substrates can be summarized as follows:

Step 1: Identify the substrate

Glass → Determine whether the joint is structural glazing, glass weatherproofing, or decorative/transparent sealing.

Concrete → Determine whether the joint is an expansion joint, precast joint, facade perimeter joint, or general construction joint.

Aluminum panel → Determine whether the sealant is being used for facade weatherproofing, movement joints, or another bonding application.

Step 2: Identify the movement requirement

Expected Joint Movement	Recommended Direction
±20%	Standard weatherproofing
±25%	Moderate facade movement
±35%	High-movement facade or expansion joint
±50%	Extreme movement, seismic, super-tall, or infrastructure applications

INGADA’s MS weatherproof series ranges from Class 25 to Class 50, while its silicone weatherproof series covers applications from Class 20 through Class 50.

Step 3: Select the sealant type

Substrate	Primary Application	Recommended Sealant Type	Example INGADA Products
Glass	Structural glazing / SSG	Structural silicone	SR-100, SR-102
Glass	Transparent exterior joint	Translucent/weatherproof silicone	SR-103, SR-38
Glass	Interior/decorative glass bonding	Clear MS adhesive	MS-88
Concrete	Expansion or facade movement joint	Low-modulus MS polymer	MS-625, MS-635
Concrete	High-movement/seismic joint	Class 35–50 sealant	MS-635, MS-650
Aluminum panel	Exterior facade weatherproofing	Weatherproof silicone	SR-35, SR-35L, SR-50L
Aluminum panel	High-movement facade joint	Low-modulus MS polymer	MS-635, MS-650
Aluminum + glass	Structural glazing system	Structural silicone	SR-100, SR-102

Important: A weatherproof facade joint should not automatically be treated as a structural joint. Structural glazing requires a sealant specifically designed and qualified for the structural application.

4. Glass: Choose Between Structural Silicone and Weatherproof Sealant

Glass is one of the most technically demanding construction substrates because it can be part of a structural glazing system or simply form a weather-resistant enclosure.

For Structural Glazing: Use Structural Silicone

If the sealant transfers loads within a structural glazing or curtain wall system, look for a structural silicone sealant rather than a general-purpose weatherproof product.

INGADA SR-100 1K Structural Silicone Sealant is designed for field structural glazing and curtain wall assembly, with tensile strength ≥1.8 MPa, elongation ≥300%, and ±20% movement. It is listed as ASTM C1184 compliant.

For controlled factory production, SR-102 2K Structural Silicone Sealant provides ≥2.0 MPa tensile strength, ±25% movement, and a 30–60 minute adjustable open time.

For Transparent Weatherproof Joints

Where appearance is important, a translucent silicone can provide a cleaner visual result.

SR-103 Neutral Cure Structural Silicone offers a translucent appearance, ≥350% elongation, ±25% movement, and 3,000-hour laboratory-tested UV resistance. It is positioned for glass curtain walls, skylights, and transparent structures.

Glass Selection Rule

• Structural load transfer → Structural silicone
• Exterior glass weatherproofing → Weatherproof silicone
• Transparent/invisible appearance → Translucent silicone
• Interior decorative glass bonding → Clear MS adhesive, where appropriate

5. Concrete: Prioritize Movement and Low Modulus

Concrete facade joints often experience thermal expansion, shrinkage, vibration, settlement, and structural movement.

For this reason, a high-strength rigid adhesive is not necessarily the best choice. A movement joint generally needs a sealant capable of deforming repeatedly without losing adhesion.

Low-Modulus MS Polymer for Moving Concrete Joints

INGADA MS-625 Low-Modulus Polyether Sealant is designed for precast and prefab applications. It provides Class 25 movement capability, a tensile modulus of 0.4 MPa, 3,000-hour UV resistance, and joints up to 50 mm. Applications include infrastructure expansion joints, curtain walls, prefab buildings, and green building projects.

For more demanding joints, MS-635 Ultra-Low Modulus Expansion Joint Sealant provides Class 35 movement, ≥600% elongation, 3,000-hour UV stability, and 5,000 fatigue cycles. It is intended for curtain walls, bridge expansion joints, tunnels, seismic zones, and major infrastructure.

For extreme movement, MS-650 High-Movement Joint Sealant reaches Class 50 movement with ≥780% elongation and is positioned for super-tall buildings, seismic zones, and long-span infrastructure.

Concrete Selection Rule

Concrete + normal movement → MS-625

Concrete + high movement → MS-635

Concrete + extreme/seismic movement → MS-650

The final selection should be verified against the actual joint design, dimensions, substrate condition, and project specification.

6. Aluminum Panel: Select for Weathering, Movement, and Staining Risk

Aluminum composite panels and other metal facade panels are exposed to substantial thermal movement because metal can heat and cool rapidly.

The critical factors are therefore:

• UV resistance
• Joint movement
• Adhesion to the specific coating or finish
• Staining/migration compatibility
• Long-term weatherability

For standard exterior applications, a Class 25 or Class 35 weatherproof sealant may be appropriate depending on the joint design.

INGADA SR-35 High-Performance Curtain Wall Silicone provides Class 35 movement and a stated service temperature range of -40°C to 150°C. It is designed for high-performance curtain walls.

Where a low-modulus formulation is preferred, SR-35L provides Class 35 movement and zero-migration positioning for natural stone curtain wall applications.

For extreme movement, SR-50L Ultra-Low Modulus Weatherproof Silicone provides Class 50 movement and is positioned for super-tall curtain walls.

Aluminum Panel Selection Rule

Aluminum facade + moderate movement → SR-25 / SR-35

Aluminum facade + high movement → SR-35 / SR-50L

Aluminum facade + extreme movement → SR-50L or an appropriate Class 50 MS polymer

Always confirm adhesion to the actual aluminum finish, coating, anodized layer, or composite panel surface before full-scale installation.

7. Facade Sealant Selection Matrix

For architects, facade contractors, and distributors, the following matrix provides a simplified selection framework.

Project Condition	Key Requirement	Preferred Sealant Category	Example
Glass curtain wall	Structural load transfer	Structural silicone	SR-100 / SR-102
Glass skylight	UV + transparency	Translucent silicone	SR-103 / SR-38
Concrete expansion joint	Low stress + movement	Low-modulus MS polymer	MS-625
Concrete seismic joint	Extreme movement	Class 35–50 MS polymer	MS-635 / MS-650
Aluminum curtain wall	Exterior weatherproofing	Weatherproof silicone	SR-35
Super-tall aluminum facade	Extreme movement	Ultra-low-modulus silicone	SR-50L
Facade movement joint	Paintability + flexibility	MS weatherproof sealant	MS-635 / MS-650
Natural stone facade	Low migration	Low-migration/zero-migration sealant	SR-35L

INGADA’s application guide maps curtain wall and facade projects to SR-50L, SR-35L, SR-35, MS-635, MS-650, SR-100, and SR-102, emphasizing high movement class and staining control for this segment.

8. Weighted Construction Sealant Selection Matrix

There is no single sealant that is best for every project. A weighted scoring approach can help procurement teams compare technologies according to the actual project priorities.

Illustrative scoring: 1 = low, 5 = high. These scores are a selection framework rather than laboratory test results and should not replace project-specific TDS verification.

Selection Criterion	Structural Silicone	Weatherproof Silicone	MS Weatherproof
UV resistance	5	5	4
High movement capability	4	4–5	5
Paintability	1	1	5
Structural glazing suitability	5	1	1
Low migration potential	Depends on formulation	Depends on formulation	5
Exterior facade suitability	5	5	5
Typical selection priority	Structural glazing	Weatherproofing	Movement + paintability

The matrix illustrates why the phrase “best construction sealant” is technically incomplete. The correct product is the one that satisfies the project’s required combination of performance characteristics.

9. Understanding ASTM Standards for Sealant Buyers

Standards should be treated as part of the selection process, not as a substitute for it.

Standard	What It Indicates in This Selection Context	Example INGADA Products
ASTM C920	Relevant classification framework for elastomeric joint sealants	MS-625, MS-635, MS-650
ASTM C1184	Structural silicone sealant specification	SR-100, SR-102, SR-103
ISO 11600	International classification reference used by several INGADA products	MS and silicone series
GB 16776	Structural silicone sealant requirements	SR-100, SR-102, SR-103

For example, SR-100 is listed as ASTM C1184 compliant, while MS-625 is listed with ASTM C920.

However, certification should always be checked against the specific product, color, production version, application, and project specification. Do not assume that compliance of one product automatically applies to an entire product family.

10. Common Construction Sealant Selection Mistakes

Mistake 1: Choosing by Price Alone

A lower unit price can become expensive if the sealant requires additional primer, produces excessive waste, has inadequate movement capability, or requires premature repair.

Mistake 2: Using Structural Silicone for Every Glass Application

Structural glazing and weatherproof glazing are different functions. A weatherproof sealant should not automatically be substituted for a structural glazing sealant.

Mistake 3: Ignoring Joint Movement

A sealant can have excellent adhesion but still fail if its movement capability does not match the joint design.

Mistake 4: Selecting a Rigid Adhesive for a Moving Joint

Expansion joints require controlled deformation. High hardness does not automatically mean better performance.

Mistake 5: Ignoring Substrate Finish

“Aluminum” is not one universal bonding surface. Anodized aluminum, powder-coated aluminum, painted aluminum, and composite panels may have different adhesion characteristics.

Mistake 6: Treating Every Facade Sealant as Interchangeable

Facade systems combine different materials, joint widths, movement levels, exposure conditions, and installation methods. Product selection should therefore be based on the complete joint design.

11. What Should You Ask a Building Sealant Manufacturer?

A qualified building sealant manufacturer should be able to provide more than a product catalog.

Before approving a sealant, ask for:

1. Technical Data Sheet (TDS)
2. Safety Data Sheet (SDS)
3. Relevant ASTM/ISO/EN test information
4. Movement classification
5. Tensile and elongation data where relevant
6. Application temperature range
7. UV/weathering information
8. Substrate adhesion recommendations
9. Primer requirements
10. Compatibility/staining information
11. Recommended joint dimensions
12. Batch traceability and quality documentation

INGADA states that it operates under an ISO 9001 quality management system and that selected products meet requirements including REACH, RoHS, French VOC A+, FDA, and relevant ASTM standards depending on product category and target market. Full certification and compliance documentation is available upon request.

For distributors, this documentation is particularly important because downstream contractors and specifiers often need technical evidence before approving a new sealant.

12. Why Manufacturer Support Matters in Facade Projects

The role of a building sealant manufacturer should not end when the cartridges leave the factory.

For complex facade projects, suppliers should be able to support:

• Product selection
• Substrate compatibility
• TDS/SDS documentation
• Sample testing
• Application training
• Batch traceability
• OEM/private-label requirements
• Distributor technical support

INGADA’s distributor support program includes English TDS and catalogs, marketing materials, downstream sample support, online English product training, and batch COA documentation.

This becomes especially valuable for distributors managing multiple facade and construction sealant SKUs.

13. Construction Sealant Selection: A Practical Checklist

Before placing a purchase order, confirm the following:

Question	Required Answer
What is the substrate?	Glass / concrete / aluminum / other
Is the joint structural?	Yes / No
What is the expected movement?	±20 / ±25 / ±35 / ±50%
Is the joint exposed to UV?	Yes / No
Is paintability required?	Yes / No
Is staining/migration a concern?	Yes / No
Is low modulus required?	Yes / No
Is a translucent or clear appearance required?	Yes / No
What standard applies?	ASTM / ISO / project-specific
Has substrate adhesion been tested?	Yes / No
Has the exact product been approved?	Yes / No

If several answers remain unknown, the sealant should not be selected solely from a product brochure.

14. FAQ: Construction Sealant Selection

What is the best sealant for a glass curtain wall?

For structural glazing, a structural silicone designed for the application should be considered. INGADA’s SR-100 and SR-102 are positioned for structural glazing and curtain wall applications, with ASTM C1184 listed for both products.

What sealant is recommended for concrete expansion joints?

A low-modulus, high-movement sealant is generally the appropriate category. INGADA MS-625 is a Class 25 low-modulus option, while MS-635 and MS-650 provide higher movement capability for more demanding joints.

What is a good facade sealant for aluminum panels?

For exterior aluminum facade weatherproofing, select a weatherproof sealant based on the required movement class and the specific aluminum finish. INGADA’s SR-35 and SR-50L are examples of Class 35 and Class 50 weatherproof silicone solutions for demanding facade applications.

Is MS polymer better than silicone?

Neither is universally better. Silicone is particularly strong for UV/weathering and structural glazing applications, while MS polymer can be advantageous where paintability, flexibility, solvent-free formulation, and low migration are important.

How do I choose between Class 25, Class 35, and Class 50 sealant?

Match the movement class to the actual joint design and expected movement. Class 25 is suitable for moderate movement, while Class 35 and Class 50 are intended for pr

Should a facade sealant be tested on the actual substrate?

Yes. Especial

Conclusion: Choose the Sealant by the Joint, Not by the Product Name

Effective construction sealant selection starts with the project rather than the product shelf.

For glass, first determine whether the application is structural glazing or weatherproofing.

For concrete, focus on movement, modulus, and long-term joint deformation.

For aluminum panels, prioritize weatherability, movement capability, substrate compatibility, and staining control.

A practical selection sequence is:

Substrate → Joint Function → Movement → Environment → Sealant Chemistry → Standard → Adhesion Test → Final Approval

For facade applications, this process can help engineers and contractors avoid one of the most common sealant-selection errors: choosing a technically strong product that is simply not the right product for the joint.

INGADA currently offers MS polymer, silicone structural, silicone weatherproof, and other construction adhesive/sealant series, with 41 SKUs across seven product series.

Need help selecting a construction or facade sealant?

Contact the INGADA technical engineering team at hua@ingadabondpro.com to request TDS documentation, product recommendations, or a commercial sample kit.