Materials and reconstruction

Draft · protocol 3.0.0-draft

Product identity

Minimum product attributes: manufacturer, brand, product family, SKU or model, GTIN if available, material class, declared or functional unit, dimensions, composition where known, performance certifications, relevant standard numbers, fire, moisture, thermal and acoustic properties, warranty, region, supplier, product status and last-verified date.

Do not infer engineering compliance from text similarity or marketing labels.

Environmental declarations

An EnvironmentalDeclaration reference captures:

• document ID, issuer or program operator, manufacturer and product scope;
• whether the source is product-specific, industry-average or generic;
• URL or document hash, publication and expiry dates, verification statement and verifier where available;
• applicable product category rules and the underlying LCA standard;
• declared or functional unit and conversion rules;
• the impact indicator and units, such as total versus fossil GWP, as defined by the source;
• life-cycle module values individually, not just an unexplained aggregate;
• geography, manufacturing site if known, electricity mix and transport assumptions;
• biogenic carbon treatment, Module D and end-of-life scenarios;
• data license and access restrictions, extraction confidence, review state and refresh date.

A declaration may be expired, incomplete, not directly comparable, regionally irrelevant or license-restricted. These conditions must be exposed to the user. Use epd for Environmental Product Declaration; avoid the ambiguous abbreviation epr.

Embodied carbon calculation

For each selected product and module, normalize installed quantity to the declaration’s declared unit, then compute impact = normalized_quantity × declaration module impact per declared unit. Store the normalization chain, rounding, declaration version, uncertainty and inclusion rules. Where no product declaration exists, a named generic or industry-average dataset may be used at a lower evidence grade. Do not imply a product-specific result.

Comparable alternatives

A comparison MUST disclose differences in functional performance, product category rules, lifecycle boundary, unit, geography, manufacturing vintage, transport, installation waste, expected service life and data quality.

If a comparison is invalid, return not_comparable with reasons, not a ranking. If a candidate requires extra layers or reinforcement, include them in the assembly-level cost and impact.

Decision model

Every alternative is evaluated against mandatory gates and weighted objectives.

• Gates: code and insurer-approved requirements, assembly compatibility, engineering and safety requirements, warranty constraints, coverage and contractual limits.
• Objectives: total installed cost, embodied carbon, operational impact, resilience, delivery time, maintenance, service life, waste implications, contractor effort.

Never treat an automated “LKQ match” as an engineering approval. Represent these states distinctly: proposed, technically_reviewed, engineer_approved, insurer_approved, rejected, ordered, installed, verified_installed.

A decision may set licensed_engineer_review_required: true. When critical evidence is missing, the status is needs_review, not pass.

LKQ equivalence dimensions

Intended function and use case; applicable codes and jurisdiction; grade, thickness, dimensions and installation system; structural and load requirements; fire rating and assembly listing; moisture exposure; thermal and acoustic performance; durability, service life and warranty; finish match and policy-specific requirements; availability and compatibility with adjacent materials; accessibility and historic-preservation constraints.

Two-stage ranking

1. Eligibility gate. Exclude or flag alternatives failing mandatory constraints.
2. Transparent comparison. Show carbon delta, installed-cost delta, lead time, availability, resilience changes, data quality and approval status. If weighted scoring is used, expose the weights and allow an unweighted Pareto view.

The lowest-impact option must not be recommended as automatically preferable if it costs substantially more, is unavailable, underperforms or violates policy or engineering requirements.

Commercial pricing

Capture price_source, quoted_at, valid_until, currency, region, supplier, quantity_breaks, material_cost, labor_cost, equipment_cost, freight, tax, disposal, overhead_profit, installation_complexity, lead_time, stock_status, minimum_order_quantity, returnability and confidence.

Keep estimate-book pricing, supplier quote, contractor bid and paid invoice separate. Prices may be confidential and require access controls.

Availability

Availability is time-dependent. Capture supplier and location, verified timestamp, delivery region, lead time, reserved versus unreserved stock, substitutions, inventory source and availability_status (confirmed, reported, estimated, unknown, unavailable). A generated assertion that a product is “available at a retailer” is not a live stock check.

Decision provenance

Record actor, organization, authority or role, reviewed alternatives, documents, constraints, selected option, rejection reasons, approvals, timestamps, any policy exception, and whether the installed product matched the approved product. If the selection changes during procurement, reopen the assessment and preserve the original decision record.