skill / Sustainability

EPD Compare

A Claude Code skill that compares 2+ products on GWP and other environmental impact metrics. Validates comparability, normalizes declared units, generates percentage deltas, and checks LEED v4.1 MRc2 eligibility.

specifications analysis
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What it does

Type /epd-comparator with products to compare — from parsed EPDs, research results, sheet references, or pasted data. The skill validates comparability (declared units, system boundaries, PCR alignment), generates side-by-side impact tables, calculates percentage deltas relative to the lowest-impact option, and checks LEED v4.1 MRc2 eligibility.

Install

Claude Desktop:

  1. Open Customize → Browse plugins
  2. Click + → Add marketplace from GitHub
  3. Enter AlpacaLabsLLC/skills-for-architects
  4. Install the Sustainability plugin

Claude Code (terminal):

claude install github:AlpacaLabsLLC/skills-for-architects/045-sustainability

Usage

After parsing or researching EPDs:

/epd-comparator compare the CLT EPDs I just found

Or with inline data:

/epd-comparator concrete A: 320 kg CO2e/m3, concrete B: 280 kg CO2e/m3, concrete C: 410 kg CO2e/m3

What it checks before comparing

  • Declared unit alignment — warns if units differ and normalization isn’t possible
  • System boundary — flags cradle-to-gate vs. cradle-to-grave mismatch
  • PCR alignment — notes when products use different Product Category Rules
  • EN 15804 version — flags +A1 vs. +A2 differences (AP/EP units may differ)
  • Validity — marks expired EPDs
  • EPD type — distinguishes product-specific from industry-average

Sample: CLT comparison

Generated from: three CLT EPDs (Stora Enso, Arboreal, Kalesnikoff)

Comparability check: ✓ Declared unit: All 1 m3 ✓ All product-specific, third-party verified ⚠ System boundary: Stora Enso cradle-to-grave, others cradle-to-gate — A1-A3 comparison valid ⚠ Standard: Stora Enso & Arboreal EN 15804+A2, Kalesnikoff ISO 21930 — GWP comparable ⚠ Biogenic carbon: Use GWP-fossil for fair comparison across CLT producers

MetricStora EnsoArborealKalesnikoffUnit
GWP-fossil (A1-A3)52.6111124.5kg CO2e/m3
GWP-biogenic (A1-A3)-762-857—kg CO2e/m3
GWP-total (A1-A3)-708-743124.5kg CO2e/m3
PENRE (A1-A3)8161,7002,352MJ/m3

GWP-fossil (relative to lowest): Stora Enso — baseline · Arboreal +111% · Kalesnikoff +137%

Recommendation: Stora Enso is the clear leader on fossil GWP — less than half of the North American alternatives. For North American projects, Kalesnikoff has a shorter supply chain. All three qualify for LEED MRc2 Option 1 and Option 2.

Output saves as a markdown comparison report.

Pairs with