The Short Answer

Gentek and Alside both manufacture credible vinyl siding systems. Their leading premium horizontal products—Gentek Sequoia Select and Alside Charter Oak—are especially close competitors. Both feature a nominal .046-inch thickness, full or rolled nailing hems, reinforced panel designs, 3/4-inch projections, low-maintenance finishes, darker-color technology, and ASTM D5206 wind-load testing.

Gentek Sequoia Select emphasizes its Advantage Lock system, full-roll nailing hem, deep cedar-grain appearance, and Color Clear Through coordination. Alside Charter Oak emphasizes its TriBeam design, rolled-edge nail hem, specially formulated vinyl compound, and ColorConnect system.

An Important Connection Between Gentek and Alside

Gentek and Alside are separate building-product brands, but both operate within the broader Associated Materials organization. That helps explain why some terminology, color technologies, design approaches, and warranty concepts may appear similar across the two product families.

This corporate relationship does not mean every Gentek and Alside panel is identical. Product profiles, locks, nail hems, packaging, colors, distribution networks, warranties, and market availability can differ. Buyers should still compare the exact product numbers and current technical documents.

Begin With VSI Certification and ASTM Standards

Manufacturer features are important, but recognized standards provide a more reliable starting point. The Polymeric Exterior Products Association, formerly known as the Vinyl Siding Institute, owns the VSI Product Certification Program.

The association states that its certification program uses independent, accredited certification bodies. Products listed through the program have demonstrated compliance with the ASTM standard applicable to their product category.

• ASTM D3679: Standard Specification for Rigid Polyvinyl Chloride Vinyl Siding. It addresses requirements involving materials, dimensions, weatherability, impact resistance, expansion and shrinkage, surface distortion, and wind-load resistance.
• ASTM D5206: A test method used to evaluate rigid vinyl siding under negative wind-load pressure.
• ASTM D4756: Standard practice covering the installation of rigid vinyl siding and soffit.
• ASTM D7793: Standard specification applicable to insulated vinyl siding.
• ASTM D7254: Standard specification applicable to polypropylene siding products.

These standards create a meaningful performance baseline. They do not make every panel equal. Thickness, profile design, material formulation, nail-hem construction, locking system, color technology, and installation details can still vary.

Gentek and Alside at a Glance

Specifications vary by product, profile, color, market, and installation configuration. Verify current manufacturer literature before ordering.

Premium Comparison: Gentek Sequoia Select vs. Alside Charter Oak

Sequoia Select and Charter Oak provide the most direct comparison between the two brands. Both manufacturers publish a nominal .046-inch thickness for their premium horizontal profiles. Both also use reinforced attachment and profile engineering to improve rigidity and wind-load performance.

Where Sequoia Select Stands Out

Sequoia Select offers four traditional horizontal profiles along with a Board and Batten vertical profile. Gentek’s Color Clear Through system can also be valuable when coordinating siding with designated soffit, fascia, trim, aluminum, steel, and rainware products.

Where Charter Oak Stands Out

Charter Oak’s TriBeam construction is a central part of Alside’s product design. Alside also publishes detailed information about the ingredients and performance role of its PureStrength resin, Ti-Shield titanium dioxide, StayRight stabilizers, TrueShield impact modifiers, and DesignersChoice pigments.

Standard Comparison: Gentek Concord vs. Alside Coventry

Gentek Concord and Alside Coventry offer a sensible comparison for homeowners and builders seeking attractive, dependable vinyl siding without automatically moving into a premium .046-inch product.

Both manufacturers publish a nominal .042-inch thickness for these product lines. Both also offer multiple traditional profiles, rolled nail hems, low-maintenance finishes, coordinated accessories, and enhanced darker-color technology on designated colors.

Concord and Coventry can both be appropriate for remodeling, additions, garages, rental properties, production building, and projects where dependable performance and price are more important than selecting the heaviest available panel.

What Does .046-Inch Thickness Mean?

Both Sequoia Select and Charter Oak are marketed with a nominal .046-inch wall thickness. This places them in an extra-heavy or premium vinyl siding category compared with many common .040-inch, .042-inch, or .044-inch panels.

A heavier panel may provide:

• Greater rigidity during handling and installation
• A straighter appearance over a properly prepared wall
• Improved resistance to ordinary impacts
• More substantial panel engagement
• Deeper shadow lines when paired with a larger projection

Thickness is not a complete performance score. Nail-hem construction, lock design, panel geometry, formulation, substrate preparation, and fastening practices also affect the installed system.

Wind-Load Testing: Similar Language, Important Limitations

Gentek states that Sequoia Select has been tested for negative wind-load resistance under ASTM D5206 and meets or exceeds the applicable industry standard for wind-load performance.

Alside uses similar ASTM D5206 language for Charter Oak. Alside explains that Charter Oak’s TriBeam design and rolled-edge nail hem are intended to increase rigidity and resist intense wind forces.

The fact that both products reference ASTM D5206 does not prove that every profile has an identical design-pressure rating. ASTM D5206 describes the test method. The actual performance result depends on the specific tested configuration.

A brochure statement about wind resistance should never replace the complete product specification, code calculation, and manufacturer installation instructions.

Comparing Color Technology

Gentek and Alside both use ChromaTrue technology on designated darker colors. This connection is not surprising given their shared corporate organization, but color availability still differs between the brands and individual product lines.

Gentek pairs its colors with the Color Clear Through system. Alside uses its ColorConnect system. Both approaches are intended to make it easier to coordinate siding with selected soffit, fascia, trim, rainware, and accessory products.

Insulated Siding Requires a Different ASTM Comparison

Alside Prodigy is a one-piece insulated siding system that combines a vinyl panel with contoured expanded polystyrene insulation. Alside highlights its RigidLock connection, extended panel lengths, insulated accessories, moisture permeability, added impact resistance, and thermal performance.

Insulated siding should not be compared directly with an uninsulated panel based only on thickness. The applicable product standard for insulated vinyl siding is ASTM D7793, while ASTM D3679 applies to conventional rigid vinyl siding.

If insulation is a project priority, compare complete insulated systems using their published R-values, thicknesses, water-vapor characteristics, installation requirements, fire-test data, code documentation, and written warranties.

Installation Quality Remains Decisive

Vinyl siding expands and contracts as outdoor temperatures change. It must be attached securely while remaining free to move. Driving fasteners too tightly, failing to provide clearance inside receiving channels, or stretching panels upward can cause buckling, distortion, and visible waviness.

ASTM D4756 provides an industry-recognized installation practice. Manufacturer instructions then provide the details for the selected product and profile.

1. Prepare a flat, structurally sound substrate.
2. Install the required water-resistive barrier and flashing.
3. Use the manufacturer-approved fastener type and length.
4. Position fasteners correctly within the nail slots.
5. Do not drive fasteners tightly against the nail hem.
6. Provide temperature-appropriate clearance at trim channels.
7. Fully engage the panel locks without forcing panels upward.
8. Follow profile-specific fastening schedules for high-wind applications.
9. Use approved details around windows, doors, corners, and penetrations.

A correctly installed standard panel can outperform an improperly installed premium panel. The installer’s knowledge and workmanship remain as important as the selected brand.

Comparing Warranty Protection

Gentek states that Sequoia Select is backed by a lifetime limited, non-prorated, transferable warranty with hail protection and lifetime fade coverage, subject to the complete written terms.

Alside states that Charter Oak and qualifying accessories are backed by lifetime limited warranties. Its brochure directs buyers to the current written warranty for the complete coverage, limitations, and exclusions.

Before purchasing either product, examine:

• Original-owner eligibility
• Transferability to a future owner
• Proration after transfer
• The definition of excessive fading
• Hail coverage and limitations
• Labor, removal, freight, and disposal coverage
• Registration and claim requirements
• Exclusions involving improper installation

Warranty language can change. The current written warranty—not a salesperson’s summary—is the controlling document.

Local Inventory Can Change the Best Choice

Product performance is not the only real-world consideration. Contractors also need materials to arrive accurately and on schedule.

Gentek’s local availability through Suburban Wholesale & Supply can provide an important operational advantage for Quad Cities contractors. Deep local inventory can help:

• Reduce special-order lead times
• Keep installation crews working
• Replace damaged or mismeasured pieces quickly
• Coordinate siding with trim and accessories
• Reduce excess jobsite inventory
• Protect contractor cash flow
• Provide access to experienced local support

That does not make Alside an inferior product. It means availability, delivery, and distributor support belong beside thickness, wind testing, color, and warranty when making a responsible purchasing decision.

Which Brand Is the Better Fit?

Final Gentek vs. Alside Comparison

Gentek and Alside both offer strong vinyl siding choices. Their shared corporate connection helps explain several similarities, but the brands maintain distinct product names, profiles, design systems, distribution networks, and technical documents.

Sequoia Select and Charter Oak are closely matched premium products. Concord and Coventry offer comparable .042-inch value-oriented choices. Alside also provides a notable insulated option through Prodigy, while Gentek can provide a powerful practical advantage when its siding and accessories are stocked locally for prompt delivery.

The best decision comes from comparing equivalent products, confirming current VSI certification, reviewing ASTM-based performance information, examining physical samples, reading the written warranties, and selecting an installer who follows manufacturer requirements and industry-approved practices.

Technical References

1. Polymeric Exterior Products Association — VSI Product Certification Program
2. ASTM International — ASTM D3679, Standard Specification for Rigid PVC Siding
3. Gentek — Sequoia Select Manufacturer Specifications
4. Alside — Charter Oak Manufacturer Brochure and Specifications
5. Alside — Coventry Manufacturer Brochure and Specifications
6. Alside — Prodigy Insulated Siding Manufacturer Brochure

Product offerings, profiles, colors, certification status, warranties, and specifications can change. Confirm all information using current manufacturer documents, applicable building codes, written warranties, and current VSI certification listings before specifying or installing siding. ASTM D5206 identifies a test method; it does not establish that every tested product has the same design-pressure rating.