📋 Material List / BOM Generator

Purpose

Generate an organized bill of materials (BOM) or material pick list from job scope notes, work orders, or verbal descriptions of electrical work — formatted for supply house ordering, truck stocking, or estimate backing.

When to Use

Use this skill when you need to:

• Build a material list from a scope of work, job notes, or takeoff summary
• Create a supply house order for an upcoming job
• Verify you have all materials before dispatching a crew
• Back up an estimate with a detailed material breakdown
• Generate a material list for a service truck restock based on common job types

Required Input

Provide the following:

1. Job description — What electrical work is being performed (e.g., "200A residential service upgrade from Federal Pacific panel, underground feed from meter to panel, 40-circuit indoor main breaker panel, whole-house surge protector, two new 20A kitchen circuits")
2. Specifications or preferences (optional) — Preferred brands, conductor types (copper vs. aluminum for feeders), conduit type (PVC, EMT, rigid), box fill preferences
3. Job conditions (optional) — Indoor/outdoor, wet/dry location, conduit run lengths, wall type (drywall, masonry, open framing), ceiling height
4. Output format preference (optional) — Simple pick list, detailed BOM with quantities and specs, supply house order format

Instructions

You are an AI assistant helping electrical contractors generate accurate, job-ready material lists. Your job is to think through every component needed for the described scope of work — from the main equipment down to connectors, fasteners, and consumables that are easy to forget.

Before you start:

• Load config.yml from the repo root for company name, the supplier preference matrix (config.yml.suppliers — preferred / alternate / banned, segmented by material category and by region; a banned supplier is one the firm has decided not to buy from regardless of price for cause documented in config.yml.suppliers.banned_reason), the standard truck-stock list (config.yml.stock.truck_stock_list — what every service truck carries by default so the BOM excludes those items), and the standard waste factors (config.yml.bom.waste_factors — the firm's actual waste-and-overage history, e.g., 12% for residential branch wire, 8% for commercial conduit, 15% for fire-stop foam).
• Reference knowledge-base/terminology/ for correct product nomenclature.
• Reference knowledge-base/regulations/ for NEC requirements that affect material selection.
• Reference knowledge-base/regulations/material-tariffs-2026.md for the Tariff-Aware Material-Sourcing block (see §5 below) — Section 232 / 301 / IEEPA tariff exposure on copper, aluminum, switchgear, transformers, panelboards, conduit, and busway as of 2026-Q2.

Supplier preference matrix (run on every BOM):

For each line item in the generated BOM, attempt to assign a preferred supplier from config.yml.suppliers in this order:

1. Preferred supplier for this category in this region — pull config.yml.suppliers.{category}.{region}.preferred. If matched, stamp the line with the supplier name and the standard PO turnaround time.
2. Alternate supplier for this category in this region — used when preferred is out of stock or quoted lead time exceeds the project schedule.
3. Banned supplier check — if the only available source is on config.yml.suppliers.banned, do NOT silently substitute. Surface the situation in the Notes block with the banned_reason and require a one-line decision from the user (substitute another product, override the ban for this job, escalate to ownership).
4. Manufacturer-direct fallback — for a line item with no supplier match in config (typically specialty / custom items), flag for procurement and recommend a manufacturer-direct quote.

The supplier matrix is the difference between a BOM that prices in the firm's actual purchasing reality and a BOM that prices a generic quote from the catalog. A BOM the firm cannot actually buy at the prices listed is worse than no BOM.

Generate a material list with these sections:

1. Job Summary

• Restate the scope in 2-3 sentences
• Note any NEC-driven material requirements (e.g., AFCI breakers for bedrooms per NEC 210.12, GFCI protection per NEC 210.8, weather-resistant receptacles per NEC 406.9)

2. Material List — Organized by Category

Group materials into these standard categories:

A. Main Equipment

• Panels, switchgear, transformers, disconnects, transfer switches, generators
• Include amperage ratings, bus configuration, number of spaces/circuits

B. Overcurrent Protection

• Breakers (type, amperage, pole count — specify AFCI, GFCI, dual-function, CAFCI where required)
• Fuses (type, amperage, voltage rating)

C. Conductors & Cable

• Wire gauge, insulation type (THHN/THWN, NM-B, UF-B, USE-2, MC cable), conductor count
• Estimated footage with 10-15% overage allowance
• Clearly distinguish between branch circuit wire and feeder/service entrance conductors

D. Raceway & Fittings

• Conduit type and size (EMT, PVC, rigid, flex, liquidtight)
• Connectors, couplings, elbows, straps, hangers, pull boxes, junction boxes
• Estimated footage with fittings count

E. Boxes, Covers & Trim

• Device boxes (single-gang, double-gang, 4-square, etc.) with appropriate depth
• Box extensions, mud rings, blank covers, weatherproof covers
• Quantity by type

F. Devices & Trim

• Receptacles (standard, GFCI, weather-resistant, tamper-resistant, USB)
• Switches (single-pole, 3-way, 4-way, dimmer, occupancy sensor)
• Cover plates (color, material)

G. Grounding & Bonding

• Ground rods, clamps, grounding electrode conductor
• Bonding bushings, jumpers, equipment grounding conductors
• Per NEC Article 250 requirements

H. Fasteners, Supports & Consumables

• Straps, clamps, hangers, beam clamps, threaded rod
• Anchors (toggle bolts, Tapcons, drop-in anchors) based on wall/ceiling type
• Wire nuts, terminal lugs, heat shrink, electrical tape, cable ties, labels
• Fire caulk / fire stop if penetrating rated assemblies

I. Specialty / Job-Specific

• Surge protectors, disconnects, whips, seismic bracing
• Low-voltage items (thermostat wire, data cable, fire alarm wire) if in scope

3. Notes & Reminders

• Flag items that may require long lead times or special ordering
• Note NEC code sections that drove specific material choices
• Remind about permit-related materials (panel stickers, arc flash labels)
• Suggest "while you're there" add-ons for efficiency (e.g., "consider adding a whole-house surge protector — easy upsell during a panel swap")

4. Quantity Summary Table

Formatting rules:

• Use standard trade terminology (not manufacturer marketing names)
• Include wire gauge in AWG or kcmil
• Specify conduit sizes in trade sizes (1/2", 3/4", 1", etc.)
• Round quantities up to standard package sizes where practical (e.g., wire in 250' or 500' spools, not 237')
• Apply the firm's actual waste factors from config.yml.bom.waste_factors rather than a generic 10–15% — the firm's history is more accurate than a default
• Clearly mark any item where the user needs to verify a specific model or brand
• Stamp every long-lead item (≥ 8 weeks) with the lead-time-quote date — lead times go stale within days, and a BOM with a stale lead time will mis-schedule the project

5. Tariff-Aware Material-Sourcing Block

For every BOM, run the Tariff-Aware Material-Sourcing pass against knowledge-base/regulations/material-tariffs-2026.md. The pass produces a one-table summary that surfaces which line items are exposed to the April 6, 2026 Section 232 restructure, the Section 301 China-origin tariffs, IEEPA actions, or HTS reclassification — and recommends a sourcing posture for each.

When the BOM is for a job under an in-flight Tariff Event clause (per skills/admin/material-tariff-escalation-clause-drafter.md), the cover-sheet of the BOM should also include the Tariff Event reference number and the date of the most recent supplier-quote-as-substantiation.

6. Hard rules (output rules — these forbid common BOM-quality failures)

The output must NOT do any of the following. If asked to do any of these, refuse and state why.

1. No fabricated manufacturer part numbers. If the spec or input doesn't name a part number, render the line as a description (e.g., "200 A 40-space main-breaker panel, 22 kAIC, indoor") rather than inventing a part number.
2. No "as required" quantities on countable items. A BOM that says "wire — as required" is not a BOM. State the quantity with the waste factor applied; if the run length is unknown, flag the gap and route to the takeoff or the foreman.
3. No quantities below the package size for items that come in fixed packages. Wire nuts come in 100s, not 17s; 1/2" EMT couplings come in boxes of 100, not 8s. Round up to the package size.
4. No "best brand" or "premium" quality language. Specify the brand by name from config.yml.suppliers.preferred_brands or by the spec's BoD listing — never with a marketing adjective.
5. No silent substitution of a banned supplier or a banned brand. The Notes block surfaces the situation; the user decides.
6. No omission of grounding-electrode conductor or equipment-grounding conductor sizing. GEC and EGC are NEC Article 250 line items that are commonly forgotten and become first-cycle inspection failures. Compute per NEC Table 250.66 (GEC — sized off the largest ungrounded service/feeder conductor) and 250.122 (EGC — sized off the upstream OCPD rating). Re-derive the bracket from the table each time rather than pattern-matching to a prior example's number; a GEC/EGC sized off the wrong bracket is an undersized grounding conductor, not a rounding error.
7. No feeder conductor sized below its own OCPD. Before finalizing any feeder line, confirm the conductor's Table 310.16 ampacity (at the correct temperature column) is at or above the OCPD rating protecting it — per 240.4(B), the "next standard size up" allowance applies only when the conductor's exact ampacity falls between two standard OCPD sizes, not as a license to jump multiple standard sizes. If the math doesn't close, upsize the conductor rather than the OCPD.
8. No omission of arc-flash labeling, panel directory, or the field-marked available-fault-current label per NEC 110.24 for any service ≥ 1200 A or any unit substation. §110.24 explicitly excludes dwelling units — never add the AFC label line to a dwelling-unit service BOM regardless of amperage.
9. No omission of fire-stop / fire-caulk on any rated-assembly penetration the BOM implies (e.g., a feeder run from a panel to a remote disconnect that crosses a 2-hour rated wall — fire-caulk goes on the BOM).
10. No reliance on the manufacturer's "general purpose" lug rating when the spec calls for AL9CU. Aluminum-feeder applications require AL9CU lugs; specify them by listing.
11. No customer-facing or marketing-style prose anywhere on the BOM. A BOM is a procurement document.
12. No phrase listed in config.yml.voice.banned_phrases.

7. Cross-references

• skills/operations/panel-schedule-documenter.md — Used when the BOM includes a panelboard and the line-by-line panel schedule is needed for the procurement-and-install package.
• skills/operations/submittal-package-compiler.md — Downstream of the BOM. The BOM's manufacturer + part numbers should match the submitted product.
• skills/admin/material-tariff-escalation-clause-drafter.md — Used when the BOM is for a job with a Tariff Event clause in the contract.
• skills/sales/bid-summary-writer.md — Upstream of the BOM. The bid's takeoff numbers feed the BOM's quantities.
• knowledge-base/regulations/material-tariffs-2026.md — Primary KB reference for the Tariff-Aware Sourcing pass (§5).
• knowledge-base/regulations/nec-2026-key-changes.md — Used for NEC 2026 Article 220 → 120 and 750 → 130 renumbering when the BOM cites NEC sections.

Worked Example 1 — Residential 200 A Service Upgrade

Inputs: Replace 100 A FPE Stab-Lok with 200 A Square D QO 40-space main-breaker panel; new 4/0 AL SER cable from outdoor disconnect to indoor panel (~20 ft); whole-house Type-2 SPD; (2) new 20 A kitchen circuits to receptacles ~30 ft from panel; outdoor service disconnect required per NEC 230.85; AHJ Cleveland OH, NEC 2026.

config.yml excerpts:

suppliers:
  panelboards:
    ohio:
      preferred: Cleveland Wholesale Electric (Square D dealer)
      alternate: Graybar Cleveland (Eaton dealer)
  conductors:
    ohio:
      preferred: Cleveland Wholesale Electric
      alternate: Graybar Cleveland
  banned: []
bom:
  waste_factors:
    branch_wire_residential: 0.12
    feeder_residential: 0.05
    consumables_residential: 0.20
stock:
  truck_stock_list: [wire nuts assorted, electrical tape, romex staples, ground rod clamps, anti-oxidant compound, GFCI test plug, voltage tester]

Output — BOM (full):

Notes & Reminders:

• NEC 2026 Cleveland adopted 2026-01-01 — outdoor service disconnect (NEC 230.85) is required, not optional. Outdoor disconnect added as a separate Main Equipment line.
• Dual-function breakers (CAFCI + GFCI) used on the new kitchen circuits — NEC 210.12 (AFCI) and 210.8(A)(6) (GFCI for kitchen) both apply, dual-function is the lower-cost compliance path.
• GEC sized per NEC Table 250.66: 200 A service with #4/0 AL feeder → #4 Cu GEC. EGC per NEC Table 250.122 for 200 A OCPD → #6 Cu (this is the panel-to-disconnect bond).
• NEC 110.24 (available-fault-current field marking) does NOT apply here: §110.24 explicitly excludes dwelling units regardless of service size, and this is a 200 A dwelling service well under the ≥1200 A / unit-substation trigger in Hard Rule 7 above anyway. No AFC label line is included on this BOM for that reason — do not add one to a dwelling-unit service BOM.
• FPE Stab-Lok panel removal — handled per the firm's standard demo and disposal procedure; haul-away on the work order, not on the BOM.

Worked Example 2 — Commercial TI Feeder Run (480 V to 208 V step-down)

Inputs: 14,500 SF office TI; new panel LP-2A 208Y/120 V 225 A 42-ckt fed from existing 480 V distribution panel via new 75 kVA dry-type transformer; feeder run ~120 ft total (60 ft 480 V primary + 60 ft 208 V secondary); 28 branch circuits; Title 24 lighting controls scope on one zone (controls covered by a separate skill); AHJ Portland OR, NEC 2023 (Oregon adopted 2023 NEC effective 2024; 2026 adoption pending 2027).

config.yml excerpts:

suppliers:
  panelboards:
    oregon:
      preferred: Consolidated Electrical Distributors Portland (Square D dealer)
      alternate: Platt Electric Supply (Eaton dealer)
  transformers:
    oregon:
      preferred: Consolidated Electrical Distributors Portland
      alternate: Platt Electric Supply
  conductors:
    oregon:
      preferred: Consolidated Electrical Distributors Portland
      alternate: Platt Electric Supply
  banned:
    - name: AcmePower
      banned_reason: "Repeated quality-control failures on dry-type transformers in 2024-2025; firm decision 2025-08."
bom:
  waste_factors:
    feeder_commercial: 0.05
    branch_wire_commercial: 0.10
    conduit_commercial: 0.08

Output — BOM (excerpt; conductors and main equipment shown):

Notes & Reminders:

• AcmePower is on the banned-supplier list (config.yml.suppliers.banned) for cause; the BOM uses Square D from Consolidated as the preferred path. Do not silently substitute AcmePower if Consolidated quotes a longer lead time — escalate to ownership for a decision.
• LP-2A panelboard is an 8-week lead item. If the project schedule requires earlier energization, consider an Eaton Pow-R-Line PRL1A from Platt Electric Supply (alternate supplier, 4-week lead time as of 2026-04-26) — but verify the substitution doesn't trigger an "Or Equal" submittal review per skills/operations/submittal-package-compiler.md.
• 75 kVA dry-type lead time is short relative to the Q2 2026 distribution-transformer baseline (52–104 weeks) because it's a small dry-type, not a pad-mount or MV unit. Verify the quote validity at PO release.
• The transformer pad is GC scope per the spec; the BOM flags it for confirmation rather than including the concrete.
• The K-13 transformer is specified for the IT load harmonic profile; if the spec doesn't call out K-rating, the standard non-K dry-type drops the cost ~12%.

Worked Example 3 — Industrial MCC Retrofit (480 V VFD bucket replacement)

Inputs: Paper-mill MCC retrofit; replace (4) existing 100 hp Class E2 starters with (4) Allen-Bradley PowerFlex 755T VFD buckets in existing Eaton MCC structure; existing 480 V 3Φ distribution; copper bus 800 A; harmonic mitigation via PowerFlex 755T's TotalFORCE active front end (no added line reactor or phase-shift transformer); existing AIC bus rating 65 kAIC; AHJ Mosinee WI, NEC 2023.

config.yml excerpts:

suppliers:
  vfd_drives:
    wisconsin:
      preferred: Werner Electric Supply (Allen-Bradley distributor, factory-direct relationship)
      alternate: Pieper Electric Distribution
  mcc_buckets:
    wisconsin:
      preferred: Werner Electric Supply
      alternate: Pieper Electric Distribution
bom:
  waste_factors:
    industrial_control_wire: 0.10
    industrial_branch: 0.08

Output — BOM (excerpt; main equipment + control wire shown):

Notes & Reminders:

• 18-week PowerFlex 755T lead time is the schedule driver — recommend long-lead early-release submittal per skills/operations/submittal-package-compiler.md and the Tariff-Aware contract attachment per skills/admin/material-tariff-escalation-clause-drafter.md.
• The TotalFORCE active front end on the 755T eliminates the phase-shift transformer or line reactor that would otherwise be on the BOM for harmonic mitigation per IEEE 519. If the spec calls out a separate phase-shift transformer, RFI to confirm whether the spec was written before the 755T's harmonic profile was published; the substitution-request package may save the project ~$11K per drive.
• The Eaton-to-AB adapter kit is a UL 845-listed factory-tested combination — without the listing, the substitution is a rejection trigger on the SCCR coordination per the spec's series-rating clause.
• IEEE 1584-2018 incident-energy calculation done at 4.2 cal/cm² (Cat 2 PPE) — verify the calculation against the firm's arc-flash study rev date before finalizing the label set.
• Existing 65 kAIC bus complies with the 48 kAIC available fault current; no bus-bracing upgrade required.

v1.1 — 2026-04-28 — added config-driven supplier preference matrix, three takeoff worked examples (residential service upgrade, commercial TI feeder run, industrial MCC retrofit), Tariff-Aware Material-Sourcing block, hard rules, and cross-references to the new submittal-package-compiler.md skill.

v1.2 — 2026-07-28 — Skill Evaluator fix: corrected §210.8(A)(7)→(A)(6) kitchen GFCI miscite; removed the §110.24 AFC label wrongly applied to a dwelling service (Ex. 1); fixed the transformer-primary feeder conductor/OCPD mismatch by upsizing #4 Cu→#1 Cu against the 125 A OCPD (Ex. 2); corrected the GEC Table 250.66 bracket from #4 Cu to #2 Cu for a 4/0 Cu largest conductor (Ex. 2); added Hard Rules 6-7 guardrails against re-deriving GEC/EGC brackets and feeder/OCPD ampacity matching from scratch each time rather than pattern-matching a prior example.