Erection Plans in NYC: Steel & Concrete Erection Engineering for DOB

What Is an Erection Plan?

An erection plan is a set of PE-stamped engineering drawings and specifications that defines how structural members (steel frames, precast panels, precast planks, trusses) are to be lifted, positioned, temporarily supported, and permanently connected during construction. Unlike the permanent structural drawings, which show the completed building, erection plans show the construction process — an inherently dynamic and temporary structural state.

The erection phase is statistically one of the highest-risk phases of construction. Partially erected steel frames have not yet achieved their final load path and lateral stability; floors are open and fall hazards are everywhere. The erection plan, when properly prepared and followed, systematically manages these risks.

When Are Erection Plans Required in NYC?

• Structural steel erection: Required for all structural steel construction projects in NYC — new buildings, vertical additions, and steel-intensive alterations. NYC Building Code references OSHA 29 CFR 1926 Subpart R, which requires a site-specific erection plan prepared by a qualified person (typically a PE for complex projects)
• Precast concrete erection: Required for all precast concrete systems — hollow-core planks, precast beams, precast columns, and precast wall panels — particularly for temporary support and bracing during erection
• Long-span systems: Roof trusses, long-span beams, and cantilever structures require special erection engineering to address the stability of the partially erected system during different stages of construction
• Complex crane operations: Multi-crane operations, tandem picks, and picks in constrained urban sites (adjacent occupied buildings, overhead utilities, sidewalk bridges over pedestrians) require formal PE-stamped lift plans

Steel Erection Plans: Contents

A complete NYC steel erection plan includes:

• Erection sequence drawings: Plan and elevation views showing the order in which columns, beams, and braces are to be erected; which bays are to be bolted up and plumbed before crane moves; sequence for installing floor deck
• Temporary bracing: Cables, kickers, or diagonal braces (with calculated sizes and loads) required to stabilize the partially erected frame against gravity and lateral loads at each erection stage
• Column base conditions: Anchor bolt layout confirmation, grout schedule, and minimum time before column base loads can be applied
• Minimum bolts at connections: Per OSHA Subpart R, at least two bolts must be installed and tightened before a crane releases a member — the plan confirms this for all connections
• Stability analysis: Calculation confirming that partially erected frames at critical stages meet unity check requirements under self-weight and construction loads (typically including 30 psf construction live load per IBC)
• Crane pick zones: Graphic showing crane locations, pick radii, and any no-fly zones over occupied spaces or utilities

Precast Concrete Erection Plans

Precast concrete erection plans address challenges specific to heavy, non-reinforced-in-place elements:

• Precast panel bracing: Tilt-up and precast wall panels must be temporarily braced against wind and accidental lateral loads until the floor diaphragm is connected. The bracing plan specifies brace size, angle, anchor bolt into slab, and brace-to-panel connection
• Hollow-core plank bearing: Minimum bearing length (typically 3 inches per ACI requirements) and leveling pad specifications to prevent tipping
• Precast beam lifting inserts: Lifting anchor design verified against the manufacturer's load table for each pick weight and sling angle
• Grouting schedule: Minimum grout strength before seating loads can be applied to precast columns or bearing elements

Crane Engineering and Lift Plans

All cranes used in NYC construction require a NYC DOB crane permit. The crane permit process involves:

1. Crane operator's employer submits crane permit application with crane model and capacity
2. For tower cranes: a separate foundation/base design by a PE showing the crane base loads can be carried by the building structure or ground foundation
3. For complex lifts: a PE-stamped lift plan showing the pick radius, crane capacity at that radius (from crane manufacturer's load chart), total load (member weight + rigging), and confirmation that no overloading occurs

In dense NYC sites, cranes frequently work over occupied sidewalks, neighboring buildings, and utility lines. For picks within 10 feet of power lines or directly over occupied spaces, a specific engineering assessment is required to confirm safety.

OSHA 1926 Subpart R: Steel Erection

OSHA 29 CFR 1926 Subpart R (Steel Erection) — the "Colvin Standard" — sets the federal minimum safety requirements for structural steel erection on all projects in the US, including NYC. Key provisions:

Erection Sequence and Stability Analysis

The most technically complex aspect of erection engineering is the stage-by-stage stability analysis. A partially erected steel frame has fewer braced bays than the completed structure and may be more susceptible to instability. The erection engineer performs:

• Analysis of each critical erection stage (typically every 2–3 floors for tall buildings; key stages for low-rise)
• Confirms that unbraced column lengths at each stage satisfy AISC 360 stability criteria
• Identifies erection stages that require additional temporary bracing beyond what permanent design provides
• Designs temporary bracing members (tension cables or compression kickers) with adequate capacity

Responsibility for Erection Safety

In NYC, erection safety responsibility is distributed (and litigated when incidents occur):

• Erecting Contractor: Primary OSHA responsibility for safe execution; must follow the approved erection plan
• Erection Engineer (PE of erection plan): Professional liability for technical adequacy of the erection plan itself
• Structural EOR: Responsible for specifying minimum erection requirements in the permanent structural drawings (anchor bolt pattern, minimum connection bolting for stability)
• General Contractor: Site coordination, crane permits, and ensuring the erecting contractor operates within the site safety plan

NYC DOB Filing for Erection Work

Erection plans are typically included as part of the structural permit package submitted through DOB NOW: Build. Crane permits are a separate DOB application. The DOB may require that erection plans be submitted and approved before a crane permit is issued. Site safety plans (required for all NYC major buildings) incorporate the erection sequence.