Sequoia Select Ventilation Guide

Sequoia Select Hidden-Vent Soffit: Understanding the 10-Square-Inch Ventilation Rating

Gentek Sequoia Select Ultra-Premium soffit combines an extra-wide vinyl panel with concealed dual vent slots. Gentek's product webpage describes the vented profile as providing 10 square inches of ventilation per linear foot, making the rating an important part of product selection and material estimating.

That number needs to be interpreted carefully. It describes the published ventilation capacity of the vented panel—not the airflow guaranteed to reach a particular attic. Intake can still be restricted by blocked rafter bays, insulation, framing, narrow eave construction, paint, dirt, accessories, or an unbalanced exhaust system.

There is also a specification discrepancy worth identifying before materials are ordered. Gentek's current product webpage lists 10 square inches per linear foot, while its August 2026 Sequoia Select brochure states 9.6 square inches per linear foot.^[1][2] Contractors should obtain the current specification for the exact item number and use that confirmed figure in final calculations.

What Is Sequoia Select Hidden-Vent Soffit?

Sequoia Select is Gentek's ultra-premium vinyl soffit. The vented profile has a 12-inch exposure, 12-foot panel length, .044-inch nominal thickness, 3/4-inch nominal projection, and matte texture. Hidden dual vent slots provide intake openings while preserving a clean visible panel face.^[1]

Gentek also offers a matching non-vented profile. The solid and vented versions share the same general appearance, allowing a designer to distribute intake where required without switching to an obviously different soffit family.

The vented profile's principal published characteristics are:

• 12-inch exposure per panel
• 12-foot panel length
• .044-inch nominal panel thickness
• 3/4-inch nominal projection
• Matte texture
• Hidden dual vent slots
• Published ventilation of approximately 10 square inches per linear foot

Current profile, color, carton, and availability information can be reviewed through Suburban Wholesale's Sequoia Select soffit product page.

What Does “Per Linear Foot” Mean?

The rating is based on the installed linear footage of vented soffit panel. It is not a square-foot rating for the attic floor, roof, or soffit surface.

One installed linear foot of the vented profile contributes the manufacturer's stated number of square inches of ventilation. Using the brochure's 9.6-square- inch rating, 20 linear feet of unobstructed vented Sequoia Select would provide 192 square inches of nominal ventilation.

These examples show product-rating arithmetic only. They do not determine the ventilation required for a particular building or prove that the completed assembly will deliver the calculated airflow.

Why the 9.6-versus-10 Difference Matters

The difference between 9.6 and 10 square inches appears small: 0.4 square inch per linear foot. Across a longer roofline, however, the difference accumulates. Sixty linear feet calculates to 576 square inches at 9.6, compared with 600 square inches at 10.

That does not necessarily mean either document is wrong. The webpage may use a rounded marketing figure while the brochure reports a more precise technical value. The problem arises when a rounded number is treated as an exact design value without confirmation.

Before relying on the rating:

1. Identify the exact Sequoia Select vented profile and item number.
2. Obtain the current manufacturer specification or product data.
3. Ask the supplier to confirm which ventilation figure applies.
4. Record the document date and rating used in the calculation.
5. Use one consistent figure throughout the estimate and project file.

This is not paperwork for its own sake. It prevents a contractor, designer, supplier, and inspector from making decisions from different versions of the same specification.

Start With the Required Intake—Not the Available Roofline

A common mistake is to count the available eave length, multiply it by the panel rating, and declare the attic adequately ventilated. That calculation shows potential product capacity. It does not establish the building's ventilation requirement.

The correct sequence is:

1. Determine the enclosed attic or roof area served.
2. Confirm the applicable ventilation requirement.
3. Determine the intended balance between intake and exhaust.
4. Calculate the intake capacity needed at the eaves.
5. Divide that required intake by the confirmed panel rating.
6. Verify that the building has enough usable eave length.
7. Confirm that air can pass from the soffit into the roof assembly.

Applicable building requirements and accepted ventilation ratios can depend on the jurisdiction, roof assembly, vapor-control provisions, and project conditions. The authority having jurisdiction and the responsible design or building professional should resolve those requirements.

Example: Converting Required Intake Into Vented Length

Assume that a project-specific ventilation calculation calls for 360 square inches of soffit intake. This number is only an example; it is not a recommendation for a particular attic.

Using the brochure's 9.6-square-inch rating:

The result should not be rounded down. It also must be translated into a practical layout. If the building has two suitable eaves, the designer may distribute the intake between them. If only part of each eave communicates with the attic, the usable vented length may be less than the visible roofline.

If the calculation lands exactly on the minimum, field obstructions and layout losses can erase the margin. A qualified professional should decide whether additional capacity or a revised system is appropriate.

The Panel Cannot Overcome a Blocked Eave

Sequoia Select can only admit air that has a continuous path beyond the panel. The hidden vent slots may be open while the space above them is blocked by insulation, wood framing, old soffit material, debris, or an improperly detailed renovation.

Inspect for:

• Insulation packed tightly against the roof deck
• Missing, crushed, or blocked ventilation chutes
• Solid wood blocking between the soffit and attic
• Existing soffit left in place without adequate openings
• Framing that interrupts the intended airflow path
• Paint, sealant, dirt, or insect nests obstructing openings
• Receiving channels positioned in a way that restricts the vent area

Covering an existing solid soffit with vented vinyl does not automatically ventilate the roof. Openings must exist behind the new panel, and those openings must communicate with the intended attic or roof cavity.

Intake and Exhaust Must Work Together

Soffit ventilation normally serves as low intake. The roof assembly also needs a compatible exhaust strategy where the design requires one. Adding more intake does not guarantee useful air movement if the exhaust is absent, undersized, blocked, or placed incorrectly.

The reverse is also true. A large ridge or roof exhaust cannot pull adequate replacement air through sealed or obstructed eaves. It may instead draw air from unintended openings in the ceiling plane.

Review the system as a whole:

• Low intake location and capacity
• High exhaust location and capacity
• Air path through each rafter bay
• Attic air sealing and insulation placement
• Separate attic areas, additions, valleys, and intersecting roofs
• Bathroom, kitchen, and dryer exhaust termination

Bath fans, kitchen exhaust, and clothes dryers should not be treated as attic ventilation. Moisture-producing equipment must discharge as required for the specific system and applicable requirements.

Distribute Vented Panels Intentionally

The matching solid profile allows vented material to be placed where intake is needed and solid material to be used elsewhere. That does not justify a random alternating pattern.

Vent distribution should follow the attic configuration and available air paths. Concentrating all vented material on one short section may leave distant roof areas poorly served, even when the total arithmetic appears sufficient.

The layout should identify:

• Which eaves serve each attic or roof cavity
• The usable vented length on every elevation
• Locations requiring solid panels
• Porches that do not connect with the attic
• Fire-separation or other conditions affecting airflow
• Obstructions around beams, returns, and additions

Do Not Confuse Panel Coverage With Ventilation Capacity

Gentek lists Sequoia Select panels at 12 feet long with 12-inch exposure. Published packaging is 16 pieces per carton and 1.92 squares per carton.^[1]

Those figures help calculate material coverage. They do not replace the ventilation calculation. A project may have enough cartons to cover the overhang but the wrong mixture of vented and non-vented panels.

The order should separately identify:

• Total soffit area
• Required linear footage of vented profile
• Required linear footage of non-vented profile
• Panel direction and cut lengths
• Waste allowance and its basis
• Receiving channels, trims, and accessories

Why Hidden Vents Improve Appearance

Conventional perforated soffit can make the ventilation pattern visually prominent. Sequoia Select places its dual vent slots in a concealed position, allowing the exposed face to read more like a solid architectural panel.

This is particularly useful on wide overhangs, front elevations, covered entries, and other areas viewed from below. The matte texture and 12-inch profile reinforce the clean-line appearance.

Hidden does not mean inaccessible to inspection. The installer still needs to protect the slots from damage and verify that they remain unobstructed after cutting, handling, and installation.

Confirm the Specification Before the Order Is Released

The conflict between the webpage's 10-square-inch figure and the brochure's 9.6-square-inch figure is exactly why current product documentation matters. Do not silently select whichever number makes the planned layout pass.

A defensible project file should contain:

1. The exact product and profile name
2. The manufacturer item number
3. The dated technical document used
4. The confirmed ventilation rating
5. The building's required intake calculation
6. The vented-panel layout by elevation
7. Documentation of the intake-to-attic air path

This article explains manufacturer product ratings and does not provide a project-specific ventilation design. Product specifications, ventilation ratings, profiles, packaging, colors, warranties, and availability may change. Verify current Gentek documents, applicable building requirements, field conditions, and the complete intake-and-exhaust design before ordering or installing materials.