Contractor Spec Pack
A contractor spec pack is a written specification document that a homeowner provides to their contractor for bidding and building a lower-risk home. It replaces verbal conversations about "healthy materials" with a document the contractor can price, order from, and be held accountable to. The Good Air Standard includes option-specific spec packs covering material categories, approved product types, prohibited materials, construction-phase air quality requirements, and verification checkpoints. Spec packs are included in the $79 Build Package — one pack for each of the 7 build options.
Why Spec Packs Matter More Than Conversations
The single most common failure mode in lower-risk construction is not material selection — it is communication. A homeowner says "I want low-VOC materials." The contractor hears "use whatever the supply house sells as low-VOC." The homeowner expects formaldehyde-free plywood; the contractor installs CARB Phase 2 compliant OSB because the supply house said it was "low-VOC." Both believe they did what was asked. Both are right based on what they understood.
A written specification eliminates this failure mode. The spec pack lists exactly what to use, what not to use, and what to do when a specified product is unavailable. The contractor bids against the document, orders from it, and the homeowner inspects against it. This changes the dynamic from "homeowner asking for special treatment" to "homeowner providing a professional specification" — a dynamic every contractor already understands from commercial work.
What Each Spec Pack Contains
Section 1: Material Specification Table
Every building component in the assembly, organized by construction phase:
| Component | Specified Category | Not Permitted | Substitution Rule |
|---|---|---|---|
| Wall sheathing | [Per build option: MgO board, exterior gypsum, plywood] | OSB | Written approval required |
| Insulation (cavity) | Mineral wool batts | Spray foam (open or closed cell) | Written approval required |
| Insulation (continuous) | Mineral wool rigid boards | EPS, XPS, polyiso foam boards | Written approval required |
| Interior wall board | Fiberglass-faced gypsum | Paper-faced gypsum | Written approval required |
| Primer | [Per paint protocol specification] | Oil-based primers, PVA primers with high VOC | Must meet emissions documentation requirement |
| Paint | [Per paint protocol specification] | Products without published emissions data | Must meet emissions documentation requirement |
| Table continues for every component in the assembly. Full tables in $79 Build Package. | |||
Section 2: Prohibited Materials List
Explicit list of materials that must not be used anywhere in the project. Cross-references Materials to Avoid. Key items:
- OSB (oriented strand board) — in any application
- Spray foam insulation — open-cell or closed-cell
- Paper-faced drywall
- Interior polyethylene vapor barrier
- Conventional particleboard or MDF (non-CARB Phase 2 compliant)
- Products without published VOC emissions data
Section 3: Construction-Phase Air Quality Requirements
Summary of the Clean Air Construction Protocol in contractor-actionable format:
- HVAC register sealing: when to seal, how to seal, when to unseal
- Directed exhaust requirements during coating and adhesive application
- Wet lumber management: moisture content testing, drying requirements per Mold During Construction Protocol
- Cure timelines for each coating system
Section 4: Verification Checkpoints
Inspection points at each construction phase where the homeowner (or their representative) verifies compliance with the specification. Corresponds to the New Construction Checklist and Homeowner Remodel Checklist.
- Pre-drywall inspection (most critical — last time to see concealed work)
- Material verification at delivery (compare delivered products to spec)
- Finishing phase start (HVAC isolation verified before coating begins)
- Pre-occupancy verification (cure periods, deep clean, air quality)
Section 5: Substitution Protocol
Written process for when a specified product is unavailable:
- Contractor notifies homeowner in writing before substituting
- Contractor provides alternative product name, manufacturer, and emissions documentation
- Homeowner reviews and approves or rejects in writing
- Approved substitutions documented in the material log
No verbal substitution agreements. No "we used something equivalent" after the fact.
Option-Specific Differences
Each of the 7 build options has a dedicated spec pack because the material requirements differ:
- Option 1: Forgiving Wood — Specifies rainscreen gap, vapor-permeable sheathing, no OSB, no interior poly. Most sections filled with standard materials available from any supply house.
- Option 2: AAC — Specifies AAC block type, thin-set mortar, exterior mineral wool board attachment, interior plaster system.
- Option 3: CMU — Specifies CMU type, grouting, exterior mineral wool, interior plaster. Mortar and sealant VOC specifications.
- Option 4: Steel Frame — Specifies steel gauge, continuous exterior insulation details, thermal bridging solutions, interior mineral board or plaster.
- Option 5: Faswall — Specifies Faswall block sourcing, stacking, concrete fill, exterior and interior finish systems. Organic content disclosure included.
- Option 6: Hempcrete — Specifies structural frame, hempcrete mix, application method, drying timeline, finish plaster. Conditional status and organic content disclosed.
- Option 7: LECA — Premium custom specification. Available through direct consultation only.
How to Use the Spec Pack
- Purchase the $79 Build Package — includes all 7 spec packs plus the Decision Worksheet to identify your option.
- Complete the Decision Worksheet to narrow to 1–2 build options.
- Review the spec pack for your chosen option. Familiarize yourself with the material categories and prohibited materials.
- Include the spec pack in your bid request. Send it with your project drawings to 2–3 contractors. Their bids should reference the specification.
- Attach the spec pack to your contract. "Contractor will follow the attached material specification" in the contract language.
- Use the verification checkpoints during construction to confirm compliance.
What the Spec Pack Is Not
- Not a substitute for construction drawings. The spec pack specifies materials and methods. It does not replace architectural plans, structural engineering, or construction documents.
- Not a legal contract. It becomes part of the contract when attached to one. On its own, it is a specification document.
- Not customized to your project. It covers the material categories for your chosen build option in general terms. Site-specific details (dimensions, quantities, structural requirements) come from your project drawings.
Last reviewed: August 2026