2026 Reference Model: Source Alignment Record Standards-Referenced Workflow Mapping Verified April 2026

Last Source Alignment Verification: April 17, 2026

Source Alignment & Citations 2026

Mapping TradeHub workflow logic to published NFPA, ACCA, and ICC standards for field-use reference alignment.

Source Navigation Index

TradeHub Source Alignment Quick Map

This index provides structured access to the master reference table and tool-specific source alignment records, with methodology and verification framework documented separately.

Standards Navigation Index

Select a source alignment record below to jump to its corresponding section.

Suite Navigation

No live plumbing source-alignment records are published yet.

No live structural or roofing source-alignment records are published yet.

Purpose

This index organizes the source ledger and active source alignment records, with methodology and verification framework maintained separately.

Engineering Manifesto

Technical Methodology & Framework

This ledger documents source alignment across active TradeHub workflow pages. To review the broader methodology, data handling posture, and verification approach, use the methodology page.

View Our Methodology

Reference Category Source Data Mapping Code Edition Source Verified
Electrical (Load/Conduit)
NFPA 70: National Electrical Code® Articles 220.82 & 120.82 · Chapter 9 Tables 1, 4 & 5
2017 2020 2023 2026 READY
Mar 29, 2026
Mechanical (ACCA/Manual J/S/D)
ACCA / ANSI Technical Manuals
Manual D: Section 12 (ASP) Manual D: Section N (Altitude) Manual D: Section 3 (Blower) Manual J (Thermal) Manual S (Equip)
ANSI/ACCA 2 (V3) & 1 (V3) Mar 29, 2026
Plumbing (IPC/IFGC)
ICC International Codes Sewer Slope (DFU) & Gas Pipe Sizing
2024 Edition Mar 29, 2026
Structural (ASCE-7/IRC 9)
ASCE-7 Minimum Design Loads Beam Span & Roof Pitch Assemblies (IRC Ch. 9)
2024 IRC / ASCE 7-22 Mar 29, 2026

Residential: Electrical Source Alignment Record

Residential Load Calculator · Source Alignment Snapshot

This section defines how the Residential Load Calculator aligns with NEC optional-method service sizing, including demand factor application, load aggregation logic, and panel capacity evaluation workflows.

NEC Optional Method Alignment Record

Primary Standards Basis

NFPA 70 Optional-Method Dwelling Load Workflow

The live residential load engine is aligned to NEC optional-method demand logic for single-family dwelling service sizing, panel-capacity review, and field-facing load schedule support.

Current source family

NFPA 70® Articles 220.82 and 120.82, with TradeHub handling year-specific optional-method differences across supported code cycles.

Mapped Logic Scope

Residential scope of alignment

Load basis

General lighting, small-appliance and laundry demand, fixed-appliance handling, and optional-method diversity application.

Major equipment

Range, dryer, tankless water-heater treatment, continuous-load handling, and equipment-side nameplate review.

HVAC and EV

HVAC demand comparison, heat-pump auxiliary treatment, EV charger inclusion, and panel-capacity benchmarking.

Field outputs

Required amps, recommended service size, shareable result links, and professional load schedule/report workflows.

Reference Defaults Posture

The tool uses bounded workflow assumptions such as required branch-circuit baselines and year-specific demand logic where the NEC optional method prescribes them. User-entered nameplate data still controls when supplied.

Verification Posture

This engine is maintained as a live source-aligned tool for residential service sizing review, with output logic aligned to published optional-method pathways and trade-facing reporting needs.

Field-Use Limitation

Local amendments, utility requirements, service equipment constraints, and AHJ interpretation remain final. This page documents source alignment; it does not replace licensed design review.

Live Tool Link

Open the Residential Load Calculator to review the corresponding live aligned workflow.

Open Residential Load Tool

HVAC BTU: Mechanical Source Alignment Record

HVAC BTU Load Calculator · Source Alignment Snapshot

This section defines how the HVAC BTU Load Calculator aligns with Manual J-style thermal load estimation, including envelope assumptions, equipment load relationships, and HVAC sizing reference workflows.

Manual J-Style Thermal Alignment Record

Primary Standards Basis

Manual J-Style Thermal Load Workflow

The live BTU engine aligns with Manual J-style thermal baseline review, regional design assumptions, directional gain handling, and preliminary HVAC sizing workflows.

Related downstream dependencies

This tool informs electrical and duct workflows by generating BTU, tonnage, and airflow reference values used later in the ecosystem.

Mapped Logic Scope

HVAC BTU scope of alignment

Envelope baseline

Structure age, insulation assumptions, regional climate baseline, and building-envelope load effects.

Solar and glazing

Directional glazing review, solar-gain weighting, and opening-related heat-load adjustments.

Sizing outputs

BTU results, tonnage guidance, airflow reference values, and report-facing HVAC sizing summaries.

Ecosystem handoff

Electrical demand handoff support and upstream airflow guidance for later Manual D-style duct evaluation.

Reference Defaults Posture

Where field measurements or manufacturer data are unavailable, the tool may apply bounded reference assumptions for envelope, infiltration, and climate-sensitive thermal workflows so the estimate remains usable.

Verification Posture

This engine is maintained as a field-facing HVAC sizing workflow and is documented here as part of the broader TradeHub thermal and mechanical alignment stack.

Field-Use Limitation

Final equipment selection, commissioning, installed-condition verification, and manufacturer compliance remain outside the software and must be confirmed by the responsible professional.

Live Tool Link

Open the HVAC BTU Load Calculator to review the corresponding live thermal alignment workflow.

Open HVAC BTU Tool

Breaker Sizing: Electrical Source Alignment Record

Breaker & Panel Load Calculator · Source Alignment Snapshot

This section defines how the Breaker & Panel Load Calculator aligns with load-to-amperage conversion, 125 percent continuous-load adjustment, and next-standard OCPD screening for field-use breaker review workflows.

NEC Breaker Sizing Alignment Record

Primary Standards Basis

Load-to-Breaker Reference Workflow

The live Breaker & Panel Load Calculator aligns with field-use breaker screening by converting connected load into amperage, applying continuous-load adjustment where required, and matching the result to the next standard breaker rating used in common one-phase 120V and 240V review workflows.

Current source family

NFPA 70® continuous-load overcurrent guidance and standard ampere rating workflow, with TradeHub using load, voltage, and runtime posture to support practical breaker-selection screening.

Mapped Logic Scope

Breaker sizing scope of alignment

Load basis

Connected load entry in watts or volt-amperes, paired with selected system voltage for amperage screening.

Continuous-load logic

125 percent adjustment workflow when the load is expected to run for 3 hours or more before breaker selection is screened.

Field outputs

Base current, adjusted amperage, next standard breaker match, utilization view, headroom note, and printable field summary output.

Workflow boundary

Field-facing OCPD screening support only; conductor ampacity, terminal limits, equipment listing, and installation conditions remain outside the calculator boundary.

Reference Defaults Posture

The workflow uses bounded reference math for common one-phase breaker review, with user-entered load, runtime posture, and voltage selection driving the screening result. It does not attempt to replace conductor sizing, equipment instructions, or full panel design review.

Verification Posture

This engine is maintained as a field-facing breaker-sizing reference workflow and is documented here as part of the broader TradeHub electrical alignment stack.

Field-Use Limitation

Final conductor sizing, equipment rating confirmation, listing requirements, local amendments, panel configuration, and AHJ interpretation remain final. This alignment record supports field-use screening; it does not replace project-specific code review.

Live Tool Link

Open the Breaker & Panel Load Calculator to review the corresponding live breaker-screening reference workflow.

Open Breaker Panel Tool

Voltage Drop: Electrical Source Alignment Record

Voltage Drop Calculator · Source Alignment Snapshot

This section defines how the Voltage Drop Calculator aligns with conductor drop screening, one-way length review, material selection, and field-facing upsizing guidance for branch-circuit and feeder workflows.

Electrical Voltage Drop Alignment Record

Primary Standards Basis

Voltage Drop Reference Workflow

The live Voltage Drop Calculator aligns with standard conductor voltage-drop formulas for field-use review, using system type, system voltage, load current, one-way length, conductor material, and conductor size to screen conductor performance before final installation decisions are made.

Related workflow dependencies

This tool supports electrical planning by helping compare conductor size choices against selected voltage-drop targets, with downstream field verification still required for ampacity, derating, installed conditions, and local code review.

Mapped Logic Scope

Voltage drop scope of alignment

Circuit review inputs

Single-phase or three-phase system type, system voltage, load current, one-way length, conductor material, and conductor size inputs.

Calculation workflow

Voltage-drop calculation in volts and percent using one-way length workflow and material-dependent resistance constants for conductor screening.

Field outputs

Status evaluation, voltage at load, target-drop comparison, recommended conductor sizing, upsizing ladder review, and max-length mode support.

Environmental allowance

Light environmental adjustment to reflect warmer or more bundled field conditions while preserving the page’s screening-first workflow posture.

Reference Defaults Posture

The workflow uses bounded reference math and user-selected review inputs to keep conductor screening usable in the field. It does not attempt to replace full ampacity, temperature-correction, conductor-derating, or terminal-rating review.

Verification Posture

This engine is maintained as a field-facing voltage-drop reference workflow and is documented here as part of the broader TradeHub electrical alignment stack.

Field-Use Limitation

Final conductor sizing, ampacity confirmation, temperature adjustment, derating, equipment instructions, local amendments, and AHJ interpretation remain final. This alignment record supports field-use screening; it does not replace project-specific code review.

Live Tool Link

Open the Voltage Drop Calculator to review the corresponding live conductor-screening reference workflow.

Open Voltage Drop Tool

Conduit Fill: Electrical Source Alignment Record

Conduit Fill Calculator · Source Alignment Snapshot

This section defines how the Conduit Fill Calculator aligns with NEC Chapter 9 raceway-fill screening, grouped conductor area review, raceway trade-size guidance, and field-facing conduit workflow support.

NEC Chapter 9 Raceway Fill Alignment Record

Primary Standards Basis

NEC Chapter 9 Raceway Fill Workflow

The live Conduit Fill Calculator aligns with NEC Chapter 9 raceway-fill screening workflow using allowable fill percentage, raceway internal area, conductor area, grouped conductor counts, and trade-size review to help electricians evaluate whether a selected conduit is likely to remain within the applicable fill limit before installation decisions are finalized.

Related workflow dependencies

This tool supports electrical planning by screening physical raceway fit for grouped conductors, surfacing upsizing guidance, and bridging back to the voltage-drop workflow when conductor regrouping or sizing changes are being considered.

Mapped Logic Scope

Conduit fill scope of alignment

Raceway review inputs

EMT, PVC Sch 40, PVC Sch 80, RMC, and IMC raceway selection with trade-size review against grouped conductor makeup.

Calculation workflow

Allowable fill from NEC Chapter 9 Table 1, raceway internal area from Table 4, and conductor-area screening from Table 5 for total grouped conductor review.

Field outputs

Fill percent, allowable fill area, grouped conductor area, recommended raceway trade size, upsizing ladder guidance, and field-facing status output.

Advanced field screening

Mixed conductor groups, parallel raceway review, pull-difficulty screening, and ampacity / derating awareness reminders to support real field installation decisions.

Reference Defaults Posture

The workflow uses bounded NEC Chapter 9 reference values and user-entered conductor makeup to keep raceway screening usable in the field. It does not attempt to replace complete ampacity, conductor adjustment, equipment-terminal, or installed-condition review.

Verification Posture

This engine is maintained as a field-facing conduit-fill reference workflow and is documented here as part of the broader TradeHub electrical alignment stack.

Field-Use Limitation

Final raceway selection, conductor makeup, ampacity confirmation, derating, installed conditions, local amendments, and AHJ interpretation remain final. This alignment record supports field-use screening; it does not replace project-specific code review.

Live Tool Link

Open the Conduit Fill Calculator to review the corresponding live raceway-fill reference workflow.

Open Conduit Fill Tool

Manual S: Equipment Selection Source Alignment Record

Manual S Equipment Selection Calculator · Source Alignment Snapshot

This section defines how the Manual S Equipment Selection workflow aligns with load intake, expanded performance screening, capacity verification, oversize review, and downstream Manual D bridge preparation.

Manual S Equipment Selection Alignment Record

Primary Standards Basis

Manual S Equipment Selection Workflow

The live Manual S workflow aligns with equipment-selection review using Manual J design loads, manufacturer expanded performance data, sensible and latent capacity checks, heating output checks, and oversize screening for field-facing reference use.

Related upstream and downstream dependencies

Manual J load inputs inform the selection screen, while blower profile, delivered airflow, static point, and device pressure-drop assumptions can carry downstream into Manual D workflows.

Mapped Logic Scope

Manual S scope of alignment

Design-load intake

Manual J total, sensible, and latent cooling loads, heating load, airflow targets, and indoor/outdoor design conditions.

Equipment screening

Brand, equipment type, nominal size, matched-system filtering, and OEM expanded performance table screening at design conditions.

Performance verification

Total cooling, sensible cooling, latent balance, heating output, and oversize-limit review for candidate pass/fail evaluation.

Manual D bridge

Blower profile, delivered airflow, static point, and device pressure-drop values prepared for downstream duct-design reference workflows.

Reference Defaults Posture

Where complete field data or manufacturer detail is unavailable, the workflow may rely on bounded reference assumptions for matching, screening, and design-condition review. User-entered project values still govern when supplied.

Verification Posture

This workflow is maintained as a field-facing equipment-selection alignment record and is documented here as part of the broader TradeHub HVAC alignment stack.

Field-Use Limitation

Final equipment selection, AHRI matching, manufacturer data confirmation, installed-condition review, and local code or AHJ interpretation remain final. This alignment record supports reference workflow use; it does not replace project-specific design responsibility.

Live Tool Link

Open the Manual S Equipment Selection workflow to review the corresponding live equipment-selection reference logic.

Open Manual S Tool

Manual D: Duct Design Source Alignment Record

Manual D Duct Design Calculator · Source Alignment Snapshot

This section defines how the Manual D Duct Design Calculator aligns with duct design workflow logic, pressure-budget review, effective length handling, and field-facing airflow diagnostics.

Tool-Specific Verification Record

Primary Standards Basis

ANSI/ACCA Manual D Duct Design Workflow

The live duct-sizing engine aligns with Manual D-style duct design relationships, pressure-budget review, effective length handling, and friction-rate workflow support for field-facing reference use.

Related upstream dependencies

Manual J load assumptions and equipment-side inputs may inform airflow targets, but this block is focused on duct-path design logic rather than whole-home load derivation.

Mapped Logic Scope

Manual D scope of alignment

Pressure workflow

Available Static Pressure, component pressure-loss budgeting, and blower-table-aware pressure review.

Path calculation

Total Effective Length, fitting equivalent length handling, and multi-path critical-path evaluation.

Sizing logic

Friction Rate workflow, airflow targets, velocity screening, and terminal-face performance checks.

Field diagnostics

Flex compression penalties, restriction alerts, warning states, and report-facing diagnostics for field review.

Reference Defaults Posture

Where installed-component data, manufacturer tables, or measured pressure losses are unavailable, the tool may apply bounded TradeHub defaults to preserve workflow continuity. Those defaults support estimation and diagnostics only.

Verification Posture

This engine is maintained as a live duct-design reference workflow for pressure budgeting, friction-rate review, and trade-facing diagnostics aligned to the broader TradeHub mechanical source stack.

Field-Use Limitation

Measured field conditions, installed layout, blower performance, manufacturer data, local code amendments, and AHJ interpretation remain final. This alignment record does not replace field verification or stamped design review.

Live Tool Link

Open the Manual D Duct Design Calculator to review the corresponding live duct-design alignment workflow.

Open Manual D Tool

Verified Tool Launch

Apply Verified Logic

Launch TradeHub reference calculators to apply NEC and ACCA-aligned logic directly to field calculations, design validation, and permit-facing documentation workflows.

Legal Notice & Methodology

TradeHub.tools is a digital data utility. Logic verification is conducted by mapping software outputs against printed source text. While we strive for 1:1 alignment with published national code tables, the onsite licensed professional and local AHJ maintain final authority over all installations and design decisions.