2026 Reference Model: Source Alignment Record Standards-Referenced Workflow Mapping Tool Verification Index

Last Source Alignment Review: May 2026

Source Alignment & Citations 2026

Mapping active TradeHub calculators to published NFPA and ACCA references, review scope, and field-use limits.

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 process documented separately.

Standards Navigation Index

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

Suite Navigation

Purpose

This index organizes active tool source records and links each calculator to its governing references, review scope, and field-use limits.

Methodology & Source Review

Technical Methodology & Verification Process

This page maps active TradeHub Trade Calculators to the code references, standards, source scope, and field-use boundaries used in each calculator. For broader methodology, data handling, and review practices, use the methodology page.

View Our Methodology

Reference Category Source Data Mapping Code Edition Source Verified
Electrical (Load, Breaker & Raceway)
NFPA 70: National Electrical Code® Articles 220.82, 210.20(A), 215.2(A), 240.6(A) · Chapter 9 Tables 1, 4, 5, 5A & 8
2017 2020 2023 2026 READY
Code Audit: May 2026
Electrical (Wire Sizing)
NFPA 70: National Electrical Code® Articles 110.14(C), 210.19(A), 215.2(A), 240.4(B), 240.4(D), 240.6(A), 310.12, 310.15, 334.80 · Table 310.16
2020 2023 2026 READY
Code Audit May 2026
Electrical (Ampacity & Derating)
NFPA 70: National Electrical Code® Articles 110.14(C), 240.4(D), 310.15, 334.80, 338.10(B)(4) · Table 310.16 · Ambient Correction & Conductor Adjustment Screening
2020 2023 2026 READY
Code Audit May 2026
Electrical (EV Charging)
NFPA 70: National Electrical Code® Article 625 · 210.20(A) · 215.2 · 240.4(D) · 240.6(A) · 310.15 · Table 310.16
2017 2020 2023 2026 READY
Code Audit May 2026
Electrical (Box Fill)
NFPA 70: National Electrical Code® Article 314.16(B) · Table 314.16(B) · 314.16(B)(1)–(5) · NEC 314.28 boundary for #4 AWG and larger pull / junction box review
2020 2023 2026 READY
Code Audit May 2026
Mechanical / HVAC (Manual J/S/D)
ACCA / ANSI Technical Manuals
Manual D: ASP / FR / TEL Manual D: Altitude Correction Manual D: Blower Data Manual J: Load Screening Manual S: Equipment Screening
ACCA Manual J / S / D References Source Review May 2026

Residential: Electrical Source Alignment Record

NEC 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 Calculator is aligned to NEC 220.82 optional-method demand logic for dwelling service sizing, panel-capacity review, HVAC/appliance/EV load treatment, and field-facing load schedule support.

Current source family

NFPA 70® Article 220.82 optional-method dwelling load calculation, with TradeHub handling supported 2017, 2020, 2023, and 2026 code-cycle differences where the optional method changes.

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 calculator is maintained as a live source-aligned field reference 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 labeling, installed conditions, and AHJ interpretation remain final. This page documents source alignment; it does not replace licensed design review or final service approval.

Live Tool Reference

Use the Residential Load Calculation tool to review the corresponding residential load reference.

Manual J: Load Screening Source Alignment Record

2026 Manual J Load Screening Calculator · Source Alignment Snapshot

This section defines how the Manual J Load Screening Calculator aligns with cooling and heating BTU review, airflow reference values, glazing exposure assumptions, and nameplate-gated electrical handoff boundaries.

Manual J Load Screening Alignment Record

Primary Standards Basis

Manual J-Style Load Screening Reference

The live calculator aligns with Manual J-style load screening for cooling BTU, heating BTU, cooling tons, airflow reference, regional design assumptions, and directional glazing exposure review. Manual J®, Manual S®, and Manual D® are registered trademarks of ACCA; TradeHub.tools is not affiliated with ACCA.

Related downstream dependencies

This tool can inform Manual S, Manual D, and electrical handoff review by producing BTU, tonnage, airflow, and equipment-context reference values.

Mapped Logic Scope

Manual J load screening scope

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

Cooling/heating BTU results, cooling-ton reference, airflow reference values, and report-facing HVAC load screening summaries.

Ecosystem handoff

Nameplate-gated electrical handoff support and upstream airflow guidance for later Manual S and Manual D-style review.

Reference Defaults Posture

Where field measurements, full design data, or manufacturer information are unavailable, the tool may apply bounded reference assumptions for envelope, infiltration, regional climate, glazing exposure, and airflow screening so the estimate remains usable.

Verification Posture

This calculator is maintained as a field-facing Manual J-style load screening reference and is documented here as part of the broader TradeHub mechanical workflow.

Field-Use Limitation

Final Manual J design, equipment selection, manufacturer data, installed-condition verification, commissioning, local requirements, and AHJ interpretation remain outside this screening reference and must be verified by the responsible professional.

Live Tool Reference

Use Tradehub's HVAC BTU Calculator tool to review the corresponding HVAC load screening reference.

Breaker Sizing: Electrical Source Alignment Record

2026 NEC Breaker Sizing Calculator · Source Alignment Snapshot

This section defines how the Breaker Size 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 Size Calculator aligns with field-use breaker screening by converting watts or VA into amperage, applying 125% continuous-load adjustment where required, and matching the result to standard OCPD ratings used in common 120V and 240V review workflows.

Current source family

NFPA 70® continuous-load and standard ampere rating workflow, including NEC 210.20(A), 215.2(A), and 240.6(A), 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 calculator is maintained as a field-facing breaker-sizing reference workflow and is documented here as part of the broader TradeHub electrical sequence from load basis to conductor sizing, ampacity review, voltage drop, and raceway checks.

Field-Use Limitation

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

Live Tool Reference

Use the Breaker Size Calculator when a known service or branch-circuit load needs breaker sizing review.

Wire Sizing: Electrical Source Alignment Record

NEC 2026 Wire Size Calculator · Source Alignment Snapshot

This section defines how the Wire Size Calculator aligns load entry, terminal ampacity, conductor-count adjustment, ambient correction, NEC 310.12 dwelling service rules, small-conductor limits, and OCPD next-size review into a field-use conductor selection workflow.

NEC 2026 Conductor Sizing Alignment Record

Primary Standards Basis

Load-to-Conductor Reference Workflow

The live Wire Size Calculator aligns with field-use conductor selection by converting load amps, watts/VA, MCA, motor FLC, or dwelling service/feeder rating into the required amp basis, checking terminal temperature limits, applying conductor-count and ambient-temperature adjustment logic, and screening the first conductor size that satisfies the governing rules.

Current source family

NFPA 70® Articles 110.14(C), 210.19(A), 215.2(A), 240.4(B), 240.4(D), 240.6(A), 310.12, 310.15, 334.80, Table 310.16, plus motor/HVAC boundary notes for Article 430 and Article 440 contexts.

Mapped Logic Scope

Wire sizing scope of alignment

Load basis

Load amps, watts/VA, MCA, motor FLC, and dwelling service or feeder rating entries are normalized into the amp basis used for conductor review.

Terminal screen

60°C and 75°C terminal temperature limits are checked against the selected conductor material and wiring method.

Derating screen

Current-carrying conductor count and ambient temperature are applied through the selected adjustment column before final acceptance.

Field outputs

Recommended wire size, governing condition, pass/fail decision table, NEC reference notes, consent-gated result boundary, ampacity handoff, voltage-drop handoff, and conduit-fill handoff.

Reference Defaults Posture

The workflow uses bounded reference values for common copper and aluminum conductors, NEC Table 310.16 ampacity columns, ambient correction factors, conductor-count adjustment factors, and the NEC 310.12 residential service sizing option where applicable.

Verification Posture

This calculator is maintained as a field-facing wire-sizing reference workflow and is documented here as part of the broader TradeHub electrical workflow between breaker sizing, ampacity/derating review, voltage drop, and conduit fill verification.

Field-Use Limitation

Final conductor selection remains subject to equipment labeling, terminal ratings, insulation type, adjustment/correction conditions, OCPD protection, raceway fill, voltage drop, local amendments, and AHJ interpretation. This alignment record supports field-use screening; it does not replace project-specific code review.

Live Tool Reference

Use the Wire Size Calculator tool to review the corresponding conductor-sizing reference.

Ampacity & Derating: Electrical Source Alignment Record

NEC Wire Derating & Ampacity Calculator · Source Alignment Snapshot

This section defines how the Ampacity & Derating Calculator aligns conductor material, Table 310.16 ampacity, 60/75/90°C terminal limits, ambient temperature correction, conductor-count adjustment, and final usable-ampacity screening into a field-use derating workflow.

NEC 2026 Ampacity Derating Alignment Record

Primary Standards Basis

Conductor Ampacity Derating Workflow

The Ampacity & Derating Calculator supports field-use review by starting with NEC Table 310.16 conductor ampacity, applying 310.15 ambient-temperature correction and current-carrying conductor adjustment, respecting terminal limits, and comparing final usable ampacity against the entered circuit load.

Current source family

NFPA 70® Table 310.16, Article 310.15 adjustment/correction, Article 110.14(C) terminal temperature limits, Article 240.4(D) small-conductor OCPD limits, 334.80 NM cable ampacity, and 338.10(B)(4) SE cable conditions.

Mapped Logic Scope

Ampacity and derating scope of alignment

Ampacity basis

Conductor material, wire size, selected insulation/temperature column, and terminal temperature basis are used to establish the starting ampacity and final allowable limit.

Temperature correction

Ambient temperature is applied through the selected correction column, with an inline Fahrenheit helper for field readability.

Conductor adjustment

Current-carrying conductor count is screened through grouped-conductor adjustment factors before final comparison.

Field outputs

Usable ampacity, total derating factor, pass/fail result, terminal-limit note, NEC reference notes, and workflow handoffs for wire size, voltage drop, and raceway review.

Reference Defaults Posture

The workflow uses bounded reference values for common copper and aluminum conductor sizes through 500 kcmil, NEC Table 310.16 ampacity columns, ambient correction factors, and conductor-count adjustment factors for field-use screening.

Verification Posture

This calculator is maintained as a field-facing ampacity and derating reference workflow and is documented here as part of the broader TradeHub electrical workflow between wire sizing, voltage drop, and conduit fill verification.

Field-Use Limitation

Final conductor ampacity remains subject to equipment labeling, terminal ratings, insulation type, installed conditions, cable or raceway fill, small-conductor limits, local amendments, and AHJ interpretation. This alignment record supports field-use screening; it does not replace project-specific code review.

Live Tool Reference

Use the Ampacity Calculator tool to review the corresponding ampacity and derating reference.

EV Charging: Electrical Source Alignment Record

EV Charger Wire Size & Breaker Calculator · Source Alignment Snapshot

This section defines how the EV Charger Circuit Sizing workflow aligns with NEC Article 625 continuous-load sizing, standard breaker selection, NM-B versus THHN/raceway screening, and maximum EVSE output review for Level 1 and Level 2 charging circuits.

NEC EV Charging Alignment Record

Primary Standards Basis

EV Branch-Circuit Reference Workflow

The live EV Charger Wire Size & Breaker Calculator aligns with residential EV charging review by converting charger output into adjusted branch-circuit demand, applying 125% continuous-load math, screening standard breaker sizes, comparing common NM-B versus THHN/raceway assumptions, and finding max EVSE output for known breaker sizes.

Current source family

NFPA 70® Articles 625, 210.20(A), 215.2, 240.4(D), 240.6(A), 310.15, and Table 310.16, paired with residential branch-circuit screening and wiring-method differentiation used for field-facing breaker and wire review.

Mapped Logic Scope

EV circuit sizing scope of alignment

Load basis

Charger output current, charging level, selected system voltage, known-breaker mode, and wiring method drive the branch-circuit screening result.

Continuous-load logic

125 percent EV charging adjustment is applied before breaker selection, with result math screened against standard OCPD increments.

Field outputs

Adjusted load, breaker match, maximum EVSE output for known breakers, typical wire guidance by wiring method, field note posture, and voltage-drop handoff for long-run review.

Workflow boundary

Field-facing EV circuit screening support only; derating, EGC sizing, equipment listing, local amendments, and final installation conditions remain outside the calculator boundary.

Reference Defaults Posture

The workflow uses bounded residential reference logic for Level 1 and Level 2 EV branch-circuit review. It differentiates common NM-B and raceway assumptions for practical field screening, but does not replace equipment instructions, derating review, or project-specific code analysis.

Verification Posture

This calculator is maintained as a field-facing EV circuit reference workflow and is documented here as part of the broader TradeHub electrical workflow, including breaker screening, wire-method context, service/load review, and downstream voltage-drop review.

Field-Use Limitation

Final conductor sizing, terminal temperature limits, equipment labeling, EVSE manufacturer requirements, receptacle configuration, load management requirements, local amendments, and AHJ interpretation remain final. This alignment record supports field-use screening; it does not replace project-specific code review.

Live Tool Reference

Use the EV Charger Circuit Sizing tool to review the corresponding EV branch-circuit reference.

Voltage Drop: Electrical Source Alignment Record

Voltage Drop & Wire Upsizing Calculator · Source Alignment Snapshot

This section defines how the Voltage Drop Calculator aligns with branch-circuit and feeder voltage-drop screening, one-way length review, conductor material selection, wire upsizing ladder, EGC upsizing review under NEC 250.122(B), and field-facing upsizing guidance.

Electrical Voltage Drop Alignment Record

Primary Standards Basis

Voltage Drop Reference Workflow

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

Related workflow dependencies

This tool supports electrical planning by comparing conductor size choices against selected voltage-drop targets, surfacing an upsizing ladder, flagging EGC upsizing review when ungrounded conductors are increased, and keeping downstream field verification required for ampacity, derating, installed conditions, and AHJ 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, conductor size, and voltage-drop target inputs.

Calculation workflow

Voltage-drop calculation in volts and percent using one-way length workflow, material-dependent resistance constants, upsizing review, and EGC upsizing prompt when conductor upsizing affects grounding review.

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 calculator is maintained as a field-facing voltage-drop reference workflow and is documented here as part of the broader TradeHub electrical workflow between conductor selection, ampacity confirmation, EGC review, and raceway fill.

Field-Use Limitation

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

Live Tool Reference

Use Tradehub's Voltage Drop Calculator tool to review the corresponding voltage-drop screening reference.

Conduit Fill: Electrical Source Alignment Record

2026 NEC Conduit Fill Calculator · Source Alignment Snapshot

This section defines how the Conduit Fill Calculator aligns with NEC Chapter 9 raceway-fill screening, grouped and mixed conductor area review, compact aluminum, bare copper grounds, jam-ratio review, 24-inch nipple treatment, parallel-raceway context, 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, mixed conductor sets, compact aluminum/bare conductor references, 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 or mixed conductors, surfacing upsizing guidance, flagging jam/pull-condition review where applicable, and bridging back to the voltage-drop workflow when conductor regrouping or sizing changes are required.

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 calculator is maintained as a field-facing conduit-fill reference workflow and is documented here as part of the broader TradeHub electrical workflow after conductor sizing, ampacity review, voltage drop, and raceway selection.

Field-Use Limitation

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

Live Tool Reference

Use the Conduit Fill Calculator tool to review the corresponding raceway-fill reference.

Box Fill: Electrical Source Alignment Record

2026 NEC Box Fill Calculator · Source Alignment Snapshot

This section defines how the Box Fill Calculator aligns with NEC 314.16(B) cubic-inch box-fill screening for conductors, equipment grounding conductors, device yokes, internal clamps, support fittings, listed ring volume, and the NEC 314.28 boundary for larger pull and junction box review.

NEC 314.16(B) Box Fill Alignment Record

Primary Standards Basis

NEC 314.16(B) Box-Fill Workflow

The live Box Fill Calculator aligns with NEC 314.16(B) box-fill screening using conductor volume allowances for #18 through #6 AWG, equipment grounding conductor allowances, device/yoke allowances, internal clamp and support fitting allowances, and total available box volume including listed ring or extension volume entered by the user.

Related workflow dependencies

This tool sits after conductor sizing and raceway planning. It screens the cubic-inch capacity of the box assembly and hands larger conductor or pull-box conditions to NEC 314.28 review instead of applying #18 through #6 box-fill math outside its source scope.

Mapped Logic Scope

Box fill scope of alignment

Box volume inputs

Manual or preset box volume, listed plaster ring / mud ring / extension ring volume, and total available cubic-inch volume reporting.

Calculation workflow

Insulated conductor allowances, standard and isolated EGC allowances, device/yoke gang allowances, internal clamps, and support fitting type counts.

Field outputs

Required volume, total available volume, remaining or deficit volume, fill ratio, NEC 314.16(B) breakdown, and printable field report output.

Boundary conditions

#18 through #6 AWG cubic-inch box-fill scope, with #4 AWG and larger pull / junction box conditions redirected to NEC 314.28 review.

Reference Defaults Posture

The workflow uses bounded NEC 314.16(B) conductor volume allowances and current-cycle EGC screening logic while preserving legacy EGC-cycle awareness where selected. It does not attempt manufacturer box catalog selection or pull-box dimensioning for larger conductors.

Verification Posture

This calculator is maintained as a field-facing box-fill screening workflow and is documented here as part of the broader TradeHub electrical workflow after load basis, conductor sizing, ampacity / derating awareness, voltage-drop screening, and raceway planning.

Field-Use Limitation

Final box selection, listed cubic-inch markings, device count, conductor count, EGC treatment, support hardware, local amendments, adopted code cycle, manufacturer instructions, and AHJ interpretation remain final. This alignment record supports box-fill screening; it does not replace project-specific code review.

Live Tool Reference

Use the Box Fill Calculator tool to review the corresponding NEC 314.16(B) box-fill reference.

Manual S: Equipment Selection Source Alignment Record

Manual S Equipment Screening Calculator · Source Alignment Snapshot

This section defines how the Manual S Equipment Screening workflow aligns with Manual J load intake, capacity checks, AHRI/OEM data status, oversize review, and Manual D readiness.

Manual S Equipment Screening Alignment Record

Primary Standards Basis

Manual S Equipment Screening Reference

The live Manual S-style workflow screens equipment against Manual J design loads using expanded performance data, sensible and latent capacity checks, heating output checks, AHRI/OEM data status, and oversize review for field-facing reference use. Manual J®, Manual S®, and Manual D® are registered trademarks of ACCA; TradeHub.tools is not affiliated with ACCA.

Related upstream and downstream dependencies

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

Mapped Logic Scope

Manual S screening scope

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, AHRI/OEM data status, and expanded performance table screening at design conditions.

Performance verification

Total cooling, sensible cooling, latent balance, heating output, oversize-limit review, and candidate screening status.

Manual D bridge

Blower profile, delivered airflow, static point, and device pressure-drop values prepared for downstream Manual D readiness review.

Reference Defaults Posture

Where complete field data, AHRI match details, or manufacturer expanded performance data are 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 Manual S-style equipment screening record and is documented here as part of the broader TradeHub mechanical workflow.

Field-Use Limitation

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

Live Tool Reference

Use the Manual S Calculation tool to review the corresponding equipment-screening reference.

Manual D: Duct Screening Source Alignment Record

2026 Manual D Duct Screening Calculator · Source Alignment Snapshot

This section defines how the Manual D Duct Screening Calculator aligns with friction rate, available static pressure, total effective length, velocity screening, blower data, altitude correction, flex penalties, and field-facing airflow diagnostics.

Tool-Specific Verification Record

Primary Standards Basis

Manual D-Style Duct Screening Reference

The live calculator aligns with Manual D-style duct screening relationships, pressure-budget review, available static pressure, total effective length, friction-rate calculation, velocity checks, altitude correction, and flex-penalty review for field-facing reference use. Manual J®, Manual S®, and Manual D® are registered trademarks of ACCA; TradeHub.tools is not affiliated with ACCA.

Related upstream dependencies

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

Mapped Logic Scope

Manual D screening scope

Pressure workflow

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

Path calculation

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

Sizing logic

Friction rate calculation, airflow targets, velocity screening, and terminal-face performance checks.

Field diagnostics

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

Reference Defaults Posture

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

Verification Posture

This calculator is maintained as a live Manual D-style duct screening reference for pressure budgeting, friction-rate review, and trade-facing diagnostics aligned to the broader TradeHub mechanical workflow.

Field-Use Limitation

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

Live Tool Reference

Use the Manual D Calculator tool to review the corresponding duct-screening reference.

Verified Tool Launch

Apply Verified Logic

Use the active TradeHub reference calculators to apply NEC and ACCA-aligned logic to field calculations, design screening, and documentation review.

Electrical Suite

NEC-aligned calculators for residential service sizing, conductor planning, ampacity review, voltage-drop analysis, and raceway fill checks.

Live Tool

Residential Load Calculator

NEC optional-method service sizing and panel capacity workflow.

Live Tool

Breaker Size Calculator

Load-to-amperage conversion, continuous-load adjustment, and standard breaker sizing workflow.

Live Tool

Wire Size Calculator

NEC ampacity, terminal-limit review, derating, and conductor selection workflow.

Live Tool

Ampacity Calculator

Table 310.16 ampacity, correction/adjustment, terminal limits, and derating screening workflow.

Live Tool

EV Charger Circuit Size Calculator

NEC Article 625 continuous-load sizing, breaker selection, and residential wire-method workflow.

Live Tool

Voltage Drop Calculator

Conductor performance, drop-percent screening, and feeder validation.

Live Tool

Conduit Fill Calculator

Raceway fill, conductor count, and compliance planning workflow.

Live Tool

Box Fill Calculator

NEC 314.16(B) cubic-inch box-volume screening and field report workflow.

Mechanical / HVAC Suite

ACCA-aligned calculators for thermal load screening, equipment selection review, and duct system design screening.

Live Tool

Manual J Load Calculator

Manual J-style cooling/heating BTU, airflow reference, and load screening workflow.

Live Tool

Manual S Calculation

Capacity screening, AHRI/OEM data status, oversize review, and equipment selection workflow.

Live Tool

Manual D Calculator

Friction-rate, available-static-pressure, TEL, and duct path screening workflow.

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.