Demolition Scope of Work: What GCs Need to Include When Buying Out a Demo Sub

Demolition looks like the simplest scope on any project — take it down and haul it away. In practice, it's one of the most dangerous scopes to underdocument. Selective demolition on an existing building without a clear scope of work creates structural risk, utility hazards, hazardous material exposure, and change order disputes before any construction begins. This guide covers what to include in a demolition scope of work, organized by the trade-specific work, package items, and the critical coordination required before any demo work starts.

Scope Type and Extent

Tip: The most important thing in any demolition scope of work is defining exactly what is NOT being demolished. "Selective demolition" scopes that don't specify what stays are more dangerous than no scope at all — they give the sub no guidance on what to protect.

• Selective vs. complete demolition: Define the scope as complete demolition (full structure to grade) or selective demolition (specified elements only within a structure remaining in service). On selective demolition, provide clear drawings showing what is to be removed, what is to be protected, and what is to be salvaged.
• Structural elements: Any demolition that involves load-bearing walls, columns, beams, or floor assemblies requires a structural engineer's demolition sequence plan. Specify that the demo sub must follow the engineer's sequence and obtain GC approval before removing any structural element. This requirement prevents progressive collapse — it is not optional.
• Phased demolition: On occupied building renovations, demolition is often phased to maintain building function and occupant safety. Specify the exact areas, floors, or zones accessible to the demo sub in each phase, and the required hoarding, dust control, and noise mitigation for each phase.
• Concrete demolition: Specify the method for each concrete element — mechanical demolition (hoe ram, breaker), diamond blade saw cutting, or controlled blasting. Confirm saw-cut depth and location before any cutting begins — saw cuts for partial slab removal must not cut rebar that is required to remain. Require a mark-up drawing showing all cut lines approved by the GC before work begins.
• Masonry demolition: Specify whether masonry is demolished by the course (hand removal) or by machine. Hand removal is required where the structure below or adjacent to the masonry is to remain. Machine demolition of masonry on existing structures requires vibration monitoring — specify maximum vibration levels in mm/s and monitoring requirements.
• Underground structure demolition: For demolition of existing slabs on grade, footings, grade beams, and foundation walls below grade: specify the demolition method, the depth of removal, and the backfill requirement after removal. Leaving existing concrete below grade without documentation creates problems for the structural sub and future owners.

Mechanical, Electrical, and Plumbing (MEP) Demolition

• Utility disconnects before demo: All utilities must be confirmed disconnected and de-energized before any structural or mechanical demolition begins. Specify which utilities must be disconnected and by whom — this is typically the GC's coordination responsibility, not the demo sub's — but the demo sub must confirm disconnection in writing before starting work.
• MEP removal extent: On partial building renovations, confirm whether the demo sub removes MEP systems to the nearest active connection point, caps and abandons in place, or leaves as-found. "Remove and cap" is the industry standard but must be specified — subs who abandon in walls create problems for every trade that follows.
• Pipe and vessel draining: Before any MEP demolition, all pipes, tanks, and equipment must be drained and purged. Specify who is responsible for draining (typically the mechanical or plumbing sub on operating systems) and the demo sub's responsibility to confirm systems are drained before cutting.

Hazardous Materials

Tip: Hazardous materials are not demolition scope — they are a separate sub-scope that must be completed before any demolition work begins. The two scopes must be clearly separated. Commingling them creates liability for the GC and the demo sub.

• Hazardous materials assessment: A pre-demolition hazardous materials assessment (designated substance survey) is required before any demolition on buildings constructed before 2000, and recommended for any renovation project regardless of age. The assessment covers asbestos-containing materials, lead-based paint, PCBs, mercury-containing devices, and designated substances per applicable occupational health legislation.
• Abatement before demolition: All identified hazardous materials must be removed by a licensed abatement contractor before demo work begins. Specify that the demolition sub must obtain written confirmation from the GC that abatement is complete before mobilizing. This is a legal and safety requirement — it cannot be an assumption.
• Contaminated soil: If below-grade demolition is adjacent to or at a site with known or suspected soil contamination, specify requirements for soil testing, handling, and disposal. Contaminated soil cannot be stockpiled, re-used on site, or disposed of at a conventional landfill without characterization testing.

Debris Removal and Disposal

• Disposal of all demolished materials: Demo sub is responsible for legal disposal of all demolished materials — structural steel, concrete, masonry, wood, MEP components. Specify tipping location or confirm the sub is responsible for identifying an approved disposal facility.
• Recycling and salvage requirements: Many projects have LEED, green building, or owner-mandated recycling requirements. Specify the diversion rate required (typically 75%+ for LEED projects), and require the sub to maintain waste tracking documentation throughout the demo scope. Concrete recycling, metal salvage, and wood salvage are the highest-volume materials in commercial demolition.
• Salvage items: Identify any items to be salvaged and turned over to the owner — architectural elements, equipment, fixtures. Provide a specific list. "Salvage as directed by owner" creates disputes — the demo sub needs a definitive list before pricing.

• Shoring and bracing: Where selective demolition removes structural elements while the building remains in service, temporary shoring must be designed by a P.Eng. and installed before any structural elements are removed. Specify that the demo sub provides temporary shoring drawings signed and sealed by a structural engineer. This is a safety-critical requirement — it is not optional on any selective demo project.
• Protection of adjacent structures and property: Specify requirements for protecting adjacent buildings, underground utilities, landscaping, and street infrastructure. On urban sites, vibration monitoring and survey monuments may be required before and during demolition.
• Dust and noise control: Specify dust suppression methods (water spray, enclosure, HEPA-filtered negative air units in occupied buildings), hoarding requirements, and noise limits for demolition equipment. Many municipalities have by-laws governing demolition noise — confirm applicable limits.
• Permits: Demolition permits are required in most jurisdictions for any structural demolition. Specify that the demo sub obtains and pays for all required demolition permits. On larger demolition projects, a demolition plan reviewed by a structural engineer may be required for permit — confirm with the AHJ.
• Temporary site security: After demolition, open excavations and structural remnants require hoarding and security fencing. Specify the demo sub's scope for temporary security — duration and extent. On phased projects, the demo sub may need to provide hoarding at each phase boundary.
• Backfill after below-grade demolition: After removal of below-grade structures, specify the backfill material, compaction requirements, and acceptance testing. Uncompacted backfill creates differential settlement under new slabs or pavements — specify this explicitly.

• Structural engineer: The demolition sub must have the structural engineer's approved demolition sequence before beginning any structural demolition. For complex selective demolition, a pre-demolition meeting with the structural engineer is required. Any field condition that differs from the demolition drawings must be reported to the GC and structural engineer before proceeding.
• Utility owners: Confirm disconnection of all services with the utility provider before demo. Gas service disconnection must be by the local gas utility — a licensed contractor cannot simply cap a live gas service. Electrical service disconnection requires coordination with the electrical utility — allow minimum 2 weeks lead time.
• Hazmat abatement contractor: Confirm clearance testing and abatement completion report before demo sub mobilizes. Clearance air monitoring results must be provided to the GC.
• New construction trades: The demo sub must leave the site in a condition that allows the construction trades to begin work. Specify grade tolerances, pile cap elevations, and slab removal limits that the new construction requires. The demo sub and the new construction subs must have a clear handoff inspection before the demo sub demobilizes.
• Owner/occupants (occupied building renovations): Specify hours of demolition work, noise restrictions, dust containment requirements, and emergency procedures. Require the demo sub to participate in a pre-demolition meeting with the building occupants' representative before starting work.