Access-limited occupied house
Option B has slightly higher material cost but materially fewer labor-hours. Shorter scaffold occupancy and less disruption may justify the labor leader after access cost is priced separately.
Home & Construction
Siding Scenario Comparison Calculator
Hold the measured facade constant while allowing each product to retain its own purchase and labor assumptions.
SIDING OPTION DECISION
Compare two product-and-labor plans on the same measured facade
Each option retains its own carton coverage, allowance, price, productivity, and labor rate. The comparison reports material, labor, cost, and surplus leaders separately.
Lower installed cost-
Option B minus A-
Lower labor hours-
Option A installed cost-
Option B installed cost-
Lower nominal surplus-
PROJECT DECISION ILLUSTRATION
Field context followed by an exact current calculation record
Hold the facade measurement constant while comparing each product's coverage, package size, labor rate, and allowance; the ledger keeps cost, hours, and surplus as separate decisions.
| Metric | Option A | Option B | B minus A | Decision boundary |
|---|
How to use
Compare products only after the facade and inclusion boundary match
- Freeze one net siding area measured under a consistent opening-deduction policy.
- Copy each option's carton coverage at the selected profile and installation orientation.
- Enter separate allowances because panel geometry, handling, and cutting loss may differ.
- Use current delivered carton prices with the same tax and accessory inclusion boundary.
- Enter observed or bid installation productivity and the matching loaded labor rate.
- Review carton, surplus, labor, material, and installed-cost differences before considering non-price performance.
Comparison fundamentals
A fair siding comparison controls five separate bases
- Common facade
- One net measured area used by both options.
- Carton coverage
- Installed face area represented by one product package.
- Product allowance
- Option-specific reserve for cuts, damage, and handling.
- Installation productivity
- Net facade area completed per direct labor-hour.
- Installed arithmetic cost
- Whole-carton material plus modeled direct installation labor.
Calculation method
Round each product on its own package basis, then add direct labor
Each option increases the common net area by its own allowance, divides by its carton coverage, and rounds cartons up. Material cost extends whole cartons by entered price. Labor divides the same net area by option productivity and multiplies by labor rate. No lifecycle or quality score is hidden inside the total.
Quote normalization
Price is comparable only when inclusions are comparable
One quote may include delivery, starter, trim, fasteners, waste, or disposal while another lists panels only. Normalize those scope differences outside the calculator or use panel-only prices for both. Do not call an omitted item a product advantage.
Productivity evidence
Installation speed depends on the actual assembly and crew
Board size, nailing pattern, prefinishing, access, stories, corners, openings, substrate repair, and crew familiarity influence production. Use records or a bid basis that matches the selected system rather than a universal square-foot rate.
Non-price decision boundary
Installed arithmetic cost is not lifecycle value
Durability, finish cycle, thermal and moisture assembly, fire classification, impact resistance, repairability, warranty, appearance, embodied impacts, and resale preference can outweigh a modest modeled cost difference. Record those factors beside—not inside—the arithmetic comparison.
Detailed calculation process
Two-option equations and default substitution
Ai = Anet × (1 + allowancei / 100)Ncartons,i = ceil(Ai / Ccarton,i)Cmaterial,i = Ncartons,i × Pcarton,iHlabor,i = Anet / productivityiCinstalled,i = Cmaterial,i + Hlabor,i × Rlabor,i
- Common net area = 2,100 ft².
- Option A order area = 2,100 × 1.08 = 2,268 ft²; cartons = ceil(2,268 / 200) = 12.
- Option A material = 12 × $245 = $2,940; labor = 2,100 / 38 = 55.263 h.
- Option B order area = 2,100 × 1.06 = 2,226 ft²; cartons = ceil(2,226 / 100) = 23.
- Option B material = 23 × $128 = $2,944; labor = 2,100 / 48 = 43.75 h.
- Each installed total adds labor at $58/h. The live ledger reports the signed B-minus-A difference and separate leaders.
The current result cards and ledger above provide the final reconciliation.
Result interpretation
Read cost, labor, and surplus as different decisions
The lower installed-cost option wins only the entered material-plus-direct-labor comparison. Lower labor may help schedule or access constraints; lower nominal surplus may reduce purchased area. Neither result proves product suitability or installed quality.
Sensitivity discipline
Change one uncertain assumption at a time
Test price, allowance, or productivity separately to see which assumption reverses the ranking. If a small change flips the decision, the quote needs stronger evidence or a wider commercial comparison rather than a confident single-point conclusion.
Evidence and data lineage
Retain both product records and the common measurement
Keep elevation takeoff, opening policy, net area, product and profile, installation manual revision, carton label coverage, color and lot, allowance rationale, supplier quote date, freight and tax treatment, labor scope, crew productivity source, wage burden, access conditions, accessory exclusions, warranty documents, estimator, and unrounded comparison output.
Limits and exclusions
What this comparison does not score
- No starter, trim, flashing, weather barrier, fastener, sealant, disposal, equipment, tax, or permit cost unless embedded consistently.
- No substrate repair, moisture, energy, fire, wind, warranty, durability, finish, maintenance, or resale analysis.
- No crew learning curve, weather downtime, price escalation, schedule risk, financing, or change-order exposure.
- No proof that either product is approved or compatible with the wall assembly.
Key terminology
Siding option terms
- Controlled basis
- Shared area and scope definitions used by both options.
- Carton coverage
- Entered installed face area per package.
- Direct labor
- Modeled installation hours multiplied by entered labor rate.
- Nominal surplus
- Purchased carton coverage above common net area.
- Sensitivity
- How the comparison changes when one assumption moves.
- Lifecycle cost
- Acquisition plus future maintenance, repair, and replacement cost, not modeled here.
Worked decision cases
A winner can change when the project constraint changes
Remote project with expensive freight
Option A uses fewer cartons but each carton is larger. Delivered freight, damage replacement, and local availability must be normalized before the panel-only material result supports procurement.
Professional basis
References for installation variables and scope control
Important note
Compare approved assemblies and complete proposals, not isolated package prices. Confirm product compatibility, installation details, water management, warranty conditions, local requirements, and contractor scope before selection.
Frequently asked questions
Why use one common net area?
It prevents measurement differences from being mislabeled as product performance.
Why can each option use a different allowance?
Board geometry, cut patterns, fragility, handling, and package rules can create different ordering loss.
Does lower installed cost mean lower project cost?
Not necessarily; accessories, removal, equipment, repairs, taxes, permits, and lifecycle costs may be outside the model.
Why report labor separately?
Labor affects schedule, access duration, crew risk, and commercial capacity even when total cost is similar.
Can I compare products with different warranty terms?
Yes for the arithmetic shown, but warranty conditions and expected service require a separate documented decision.
What if productivity is unknown?
Use a contractor's stated labor basis or comparable production record and test a range; do not invent a precise universal rate.