Major renovation - addition
Major renovation / addition: whole-house gut renovations, large-scale remodels involving structural changes, and room additions. The owner is always the homeowner. An architect or design professional is typically engaged, full permitting is required, and the project follows a structured sequence from existing-conditions assessment through closeout. Concealed conditions are the signature risk — what is found when surfaces are opened can fundamentally change scope, budget, and schedule. (Sources: S35, S37, S42, S48)
Process diagram
flowchart LR P1["Assessment + feasibility"] P2["Programming + schematic design"] P1 --> P2 P3["Design development + CDs"] P2 --> P3 P4["Permitting + builder selection"] P3 --> P4 P5["Pre-construction + abatement"] P4 --> P5 P6["Selective demo + discovery"] P5 --> P6 P7["Structural + rough-in"] P6 --> P7 P8["Finishes + changes"] P7 --> P8 P9["Closeout + warranty"] P8 --> P9
1. Assessment + feasibility
The project begins with evaluating the existing building: structural condition, MEP systems, building envelope, and potential hazardous materials. The goal is to determine whether the owner’s vision is feasible within the existing structure and to establish a preliminary scope and budget range.
Terms used in this phase: Existing conditions, feasibility, budget range
- Owner and sponsor: Defines goals, budget tolerance, and lifestyle needs. Discloses known issues.
- Architecture firms and consultants: Tests fit between goals, existing structure, and probable cost. May begin as-built documentation.
- Builder and general contractor: In Design-build delivery, engaged from the start. Otherwise, may provide informal pricing input.
- City county and state authorities (AHJ): Zoning, setbacks, and historic-overlay constraints may immediately limit options. Permit history reveals prior unpermitted work.
- Home inspector: Performs pre-renovation assessment: structural integrity, moisture, electrical safety, life-safety deficiencies, suspect hazardous materials.
- Environmental consultant and abatement contractor: Conducts hazardous-material screening (lead, asbestos) if building is pre-1978 or suspect materials are present.
- Subcontractors and trade contractors: Minimal early role except specialized assessment (structural engineer, MEP specialist).
- Vendors suppliers and distributors: Not yet engaged.
Related glossary terms: Existing conditions, Concealed conditions, Contingency
2. Programming + schematic design
The owner’s needs are translated into a conceptual design within the constraints of the existing structure. Major systems (structural, MEP) are evaluated for reuse or replacement. A preliminary budget is developed.
Terms used in this phase: Schematic design, programming, as-built, concept
- Owner and sponsor: Defines room count, lifestyle needs, aesthetic goals, and budget tradeoffs.
- Architecture firms and consultants: Creates conceptual plans, evaluates structural and MEP options, and produces as-built drawings from field measurements.
- Builder and general contractor: If engaged preconstruction, provides rough pricing and constructability input on existing-conditions constraints.
- City county and state authorities (AHJ): May require early conversations about zoning variances, historic review, or addition setbacks.
- Subcontractors and trade contractors: Structural engineer may evaluate load paths and framing capacity.
- Vendors suppliers and distributors: Early input on long-lead items if selections are time-sensitive.
Related glossary terms: Schematic design
3. Design development + construction documents
The approved schematic design is developed into detailed drawings and specifications for permitting and construction. All material and finish selections are finalized. For additions, the new structure must comply with current codes as new construction; for alterations, the IEBC determines which upgrade triggers apply.
Terms used in this phase: Design development (DD), Construction documents (CDs), Permit set, specifications
- Owner and sponsor: Approves the package that will drive price and execution. Makes consequential finish and scope decisions.
- Architecture firms and consultants: Produces detailed architectural, structural, and MEP drawings. Coordinates consultants. Specifies materials.
- Builder and general contractor: Uses documents to establish cost and execution plan. In design-build, this is iterative with design.
- City county and state authorities (AHJ): Will review this set for permit issuance under the applicable IEBC alteration level.
- Subcontractors and trade contractors: Price key scopes based on documents. Flag practical conflicts with existing conditions.
- Vendors suppliers and distributors: Product data, energy-code compliance documentation, and selections are finalized.
Related glossary terms: Design development (DD), Construction documents (CDs), Permit set, IEBC (International Existing Building Code)
4. Permitting + builder selection
Construction documents are submitted for plan review. In design-bid-build delivery, the builder is selected through competitive bid or negotiation. In design-build, the construction cost is finalized. Permit triggers vary by scope — structural changes and MEP alterations require full plan check; some work qualifies for over-the-counter permits.
Terms used in this phase: AHJ (Authority Having Jurisdiction), plan check, bid, contract, Substantial improvement
- Owner and sponsor: Selects builder (in design-bid-build) and signs construction agreement. Watches carrying cost during review.
- Architecture firms and consultants: Responds to plan-review comments and revises plans.
- Builder and general contractor: Turns estimate into contract price. Negotiates subcontracts and procurement.
- City county and state authorities (AHJ): Building, fire, zoning, historic, and floodplain reviewers may all be involved depending on scope and location.
- Subcontractors and trade contractors: Bid their portions through the builder.
- Vendors suppliers and distributors: Confirm pricing, lead times, and product availability.
Related glossary terms: Plan check - review comments, Substantial improvement, Design-build
5. Pre-construction + abatement
Before physical construction begins: long-lead materials are ordered, hazardous-material abatement is completed, temporary protections are installed (especially for occupied homes), and the construction schedule is finalized. Abatement must be completed and cleared before selective demolition can disturb any suspect materials.
Terms used in this phase: Abatement, RRP Rule, mobilization, containment
- Owner and sponsor: Prepares for disruption. May need to arrange temporary living if the scope requires vacating.
- Architecture firms and consultants: Finalizes any remaining submittals or shop-drawing approvals.
- Builder and general contractor: Develops detailed schedule, orders long-lead items, sets up site protection. Holds pre-construction kickoff meeting.
- City county and state authorities (AHJ): Trade-specific permits may be pulled. Abatement notifications filed where required.
- Environmental consultant and abatement contractor: Completes lead and/or asbestos abatement. Performs clearance testing.
- Subcontractors and trade contractors: Submit specialty items. Confirm crew availability windows.
- Vendors suppliers and distributors: Release long-lead orders (cabinets, windows, structural steel, mechanical equipment).
Related glossary terms: Abatement, RRP Rule, Selective demolition
6. Selective demo + discovery
Existing finishes, non-structural walls, and systems are carefully removed to reveal the conditions behind them. This is the phase where concealed conditions are discovered — and where the project’s real scope often becomes clear. A decision protocol (stop → assess → determine code triggers → present options → change order) governs how discoveries are handled.
Terms used in this phase: Selective demolition, Concealed conditions, Change order, Contingency
- Owner and sponsor: Approves change orders for discovered conditions. Decides whether to expand scope or hold the line. Contingency is drawn down here.
- Architecture firms and consultants: Evaluates discoveries, determines code implications, updates drawings if structural or design changes are needed.
- Builder and general contractor: Documents discoveries with photos and reports. Presents options with cost and schedule impact. Manages the change-order process.
- City county and state authorities (AHJ): May need to be consulted if discoveries trigger code-compliance escalation (e.g., IEBC level change, structural deficiency).
- Home inspector: Role is typically complete, but findings from the pre-renovation assessment inform the interpretation of discoveries.
- Environmental consultant and abatement contractor: Returns if additional hazardous materials are found during demolition.
- Subcontractors and trade contractors: Perform selective demolition. Flag field-discovered conflicts.
- Vendors suppliers and distributors: Product adjustments if discoveries change specifications.
Related glossary terms: Selective demolition, Concealed conditions, Change order, Contingency, Scope creep
7. Structural + rough-in
With existing conditions revealed and change orders resolved, structural work (foundations, framing, load-bearing modifications) and rough-in of MEP systems proceed. Municipal inspections occur at staged milestones — work cannot be concealed before it is inspected. For additions, this phase follows the same sequence as new construction.
Terms used in this phase: Under construction, framing, rough-in, inspection
- Owner and sponsor: Monitors progress and cost. May still be living in unaffected portions of the home.
- Architecture firms and consultants: Answers field questions. Issues clarifications when as-built conditions differ from drawings.
- Builder and general contractor: Superintendent runs sequence, inspections, quality, and trade coordination. Manages occupied-home logistics.
- City county and state authorities (AHJ): Inspectors check foundation, framing, rough MEP, insulation/air-sealing, and waterproofing at staged milestones.
- Subcontractors and trade contractors: Foremen and crews install structural and rough-in scopes. Electrical and plumbing work must comply with current codes for altered systems.
- Vendors suppliers and distributors: Release materials to match build sequence and site readiness.
Related glossary terms: Under construction, Superintendent
8. Finishes + changes
Drywall, flooring, cabinetry, countertops, tile, paint, fixtures, and trim are installed. Late-stage owner changes and remaining punch items converge. In occupied renovations, this is when the homeowner begins to see the result and may want to adjust — Scope creep pressure is highest here.
Terms used in this phase: RFI (Request for Information), Change order, selections, finish work
- Owner and sponsor: Final selection decisions. Late changes create downstream cost and schedule effects.
- Architecture firms and consultants: Issues minor clarifications. Reviews finish quality against design intent.
- Builder and general contractor: Controls changes, quality, and final sequence across trades. Manages selection logistics.
- City county and state authorities (AHJ): Final or near-final inspections continue.
- Subcontractors and trade contractors: Install finish scopes. Return trips for rework are expensive if late changes stack up.
- Vendors suppliers and distributors: Finish-package deliveries become timing-sensitive. Countertop templating occurs after base cabinets are installed.
Related glossary terms: Change order, RFI (Request for Information), Scope creep
9. Closeout + warranty
Final inspections, punch-list completion, final payment, lien waivers, and warranty handoff close the project. The homeowner takes possession of the completed space and begins the warranty period.
Terms used in this phase: Substantial completion, Punch list, Final completion, warranty, lien waiver
- Owner and sponsor: Conducts final walkthrough. Accepts completed work. Begins warranty relationship.
- Architecture firms and consultants: May assist in determining completeness. Reviews final state against design intent.
- Builder and general contractor: Completes punch items. Compiles closeout records: warranties, as-built drawings, owner’s manuals, lien waivers. Initiates warranty.
- City county and state authorities (AHJ): Final inspection and certificate of occupancy (if required for the scope).
- Subcontractors and trade contractors: Return for punch work and corrections.
- Vendors suppliers and distributors: Warranty data and product manuals pass to the owner.
Related glossary terms: Substantial completion, Final completion, Punch list, Occupancy - use signoff