Why the Simple Square-Foot Shortcut Fails

In siding terminology, one square generally represents 100 square feet of wall coverage. Dividing wall area by 100 may provide an early planning number, but it does not produce a complete material order.

The calculation does not automatically account for:

• Triangular gables and dormers
• Panel cuts at roof slopes
• Pattern and seam-layout requirements
• Profile-specific carton coverage
• Partial cartons and ordering increments
• Starter components and receiving channels
• Corners, window trim and mounting blocks
• Damage during handling or installation
• Panels retained for future repairs

Select the Exact Profile Before Final Estimating

Fairhaven Sound is available in several shake and scallop profiles with different exposures, dimensions and packaging. An estimate based on “shake siding” is not specific enough for ordering.

The profile selection affects:

• The number of courses required
• The number of panels per elevation
• The appearance and location of cuts
• The compatible accessories
• The number of pieces and coverage per carton
• Availability in the selected color

Use Gentek’s current product page, directory and written order information. Specifications and market availability can change, so an old brochure should not be the sole source for a current order.

Step 1: Divide the Home into Measurable Shapes

PEPA’s estimating worksheet separates walls, gable ends, dormer sides and upper gambrel walls. This approach is more reliable than trying to measure an irregular elevation as one large shape.

Step 2: Decide Which Openings to Deduct

PEPA notes that windows and doors are not always deducted from a preliminary siding estimate because keeping their area can help provide an allowance for waste. Very large openings, such as garage doors or sliding doors, may justify a partial deduction.

The decision should reflect actual panel layout. A wall with many small windows may use less visible siding, but it creates more cutting, trim and short panel sections.

Deducting the full area of every opening can make an estimate look precise while leaving the order short.

Step 3: Calculate Each Material Separately

When a design combines Fairhaven Sound with horizontal siding, board-and-batten, stone or brick, each material field should have its own takeoff.

Do not combine all wall areas and apply one overall percentage. Specialty siding used in a steep gable may have a different waste pattern from horizontal siding installed across a long rectangular wall.

Separate calculations also make it easier to verify whether the visual design matches the order.

Waste Is a Project Variable

PEPA’s estimating worksheet uses a general waste allowance, while its installation guidance also notes that waste depends on roof pitch and house-specific factors. That distinction matters.

A standard percentage may be reasonable for preliminary budgeting, but the final allowance should reflect the actual elevations.

More Waste Is Not Always Better Planning

Adding an excessive percentage “to be safe” ties up money, consumes storage space and can leave unopened cartons that may not be returnable. Ordering too little can stop the project and create availability or matching concerns.

The stronger method is a panel-level layout prepared from verified field dimensions, then rounded to the actual package quantity with an intentional contingency.

Accessories Need Their Own Takeoff

PEPA’s estimating worksheet lists accessories separately because square footage does not reveal how much trim a project needs. A small dormer may require little siding but a large amount of receiving channel relative to its wall area.

The accessory estimate may include:

• Manufacturer-approved starter components
• Inside and outside corner components
• J-channel or other receiving trim
• Utility or finish trim
• Transition bands between materials
• Window and door surrounds
• Mounting blocks for fixtures and penetrations
• F-channel and soffit receiving components
• Flashing and water-management materials
• Compatible corrosion-resistant fasteners

Accessory size must match the selected panel thickness and application. A color match alone does not establish compatibility.

Panel Length Affects Layout Efficiency

Gentek says Fairhaven Sound panels are approximately 40 percent longer than typical shake and scallop profiles. Longer panels can create uninterrupted visual lines and reduce the number of panel connections across a course.

Longer panels do not eliminate waste. The installer must still determine how panel lengths interact with:

• Wall width
• Window and door placement
• Roof slopes
• Permitted joint locations
• Pattern variation
• Reusable cut sections

Order the Complete Color and Profile Combination

Not every Gentek color is necessarily offered in every profile or market. The estimate should identify the exact profile, color, product code and package quantity rather than relying on a general color name.

Before release, compare the written order against the approved sample and elevation plan. Catching a profile or color substitution before delivery is far less expensive than discovering it after installation begins.

Consider Future Repair Stock

Retaining a small quantity of correctly labeled material may make a future localized repair easier. This is separate from installation waste: repair stock should be intentional, usable and stored correctly.

The appropriate quantity depends on the project, available storage and supplier policies. At minimum, the owner should retain:

• Usable panels from the original order
• Profile, color and product-code labels
• Selected accessory information
• The supplier invoice
• The installation date and contractor information
• Gentek’s warranty and care instructions

Random short scraps are not a substitute for a complete replacement panel when the locking features have been removed.

Verify the Jobsite Before Ordering

Plans, aerial measurements and estimating software are useful, but they may not show every projection, wall-depth change or concealed renovation condition.

Field verification should confirm:

• Actual wall dimensions
• Roof pitches and gable heights
• Window and door sizes
• Existing siding layers and wall depth
• Corner and transition locations
• Soffit and fascia conditions
• Utility penetrations and mounting blocks
• Delivery access and storage space

If concealed deterioration is likely, the contract should explain how additional materials will be authorized after demolition.

Compare Estimates by Scope, Not Only by Carton Count

Two contractors may quote different quantities because they made different assumptions. The lower number is not automatically more efficient, and the higher number is not automatically more complete.

Ask each estimator to identify:

1. The measured area assigned to each material
2. The exact Fairhaven Sound profile and color
3. The carton coverage used
4. The waste or contingency allowance
5. Which openings were deducted
6. The included trim and accessories
7. Whether soffit, fascia and rainware are included
8. Whether repair stock remains with the homeowner
9. How shortages and surplus material are handled
10. Which items may be returned or are special order

Estimating Affects the Finished Appearance

Material estimating may appear purely financial, but shortages can alter design decisions. A crew that runs short may be tempted to change a joint location, use an awkward cut or postpone one section of the exterior.

A complete order helps preserve:

• Balanced gable layouts
• Consistent pattern distribution
• Planned transition heights
• Matching corners and accessories
• Orderly completion of connected elevations

Documentation and Resale

A detailed material order does not guarantee a resale premium, but it can help establish what was installed. Future owners may need the exact profile and color for maintenance or repair.

Give the homeowner a final material schedule showing product names, codes, quantities and retained stock. Store it with the warranty, installation photographs and contractor invoice.