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How to use this checklist. Work through each category before completing construction documents or committing to a project scope. Items flagged High risk should be resolved with structural engineering input before design progresses. Document unresolved items and carry them forward as open questions in your risk register.
Structural risk on existing buildings rarely surfaces as a single dramatic failure. It accumulates through deferred maintenance decisions, undocumented past repairs, envelope systems that were never designed to work together, and the quiet pressure of code obligations that attach the moment a project crosses a statutory threshold.
This checklist is organized around the four categories where late-stage discoveries most reliably derail project schedules, budgets, and design intent. Use it as a structured conversation starter between the design team and the Structural Engineer, ideally before a scope is committed and certainly before construction documents begin.
Structural unknowns embedded in the building as-built. These are the issues most likely to be discovered mid-construction when resolution is most expensive.
Item | Risk Level | Recommended Action |
|---|---|---|
As-built drawings confirmed or assumed? Verify whether record drawings exist and reflect actual construction. Undocumented deviations from original design are common in Florida buildings constructed before 1990. | High | Action Obtain record drawings; commission structural field verification if documents are unavailable or of uncertain accuracy. |
Original design loads documented? Confirm that the structural system was designed for the occupancy and loading conditions assumed by the proposed project. Critical for change-of-occupancy or renovation work. | High | Action Request original structural calculations or commission a load capacity analysis prior to proceeding with design. |
Post-tensioned concrete confirmed or ruled out? PT slab and beam systems require specialized handling for any penetration, coring, or cutting. Identification must occur before MEP coordination begins. | High | Action Review structural drawings for PT notation; perform GPR scanning if drawings are absent or conditions are unclear. |
Prior structural repairs documented? Undocumented repairs, such as patched concrete, added members, or replaced connections, may indicate past distress events that have structural implications for new work. | High | Action Interview ownership/management; review permit history; commission visual structural assessment. |
Soil and foundation type confirmed? Foundation conditions in coastal Florida vary significantly, and spread footings, driven piles, auger cast piles, and mat slabs behave differently under renovation loading scenarios. | Medium | Action Review geotechnical report if available; scope exploratory investigation for projects adding significant load or altering load distribution. |
Structural system type identified for wind resistance? Lateral load resistance, including shear walls, moment frames, and braced frames, must be understood before openings, renovations, or additions are designed. Florida’s wind environment makes this a non-deferrable item. | High | Action Confirm lateral system from record drawings; engage Structural Engineer to evaluate impact of proposed modifications on lateral load path. |
Existing slab thickness and reinforcement verified? Slab conditions govern penetration feasibility, cladding attachment capacity at the slab edge, and the viability of suspended loads from below. | Medium | Action Verify from drawings; supplement with field measurement and rebar scanning at key locations before finalizing attachment designs. |
Item | Risk Level | Recommended Action |
|---|---|---|
Concrete carbonation or chloride penetration assessed? In coastal Florida, reinforced concrete structures are at elevated risk for chloride-induced rebar corrosion. Surface staining, spalling, or rust bleed are visible indicators, but corrosion often progresses well ahead of visible symptoms. | High | Action Commission chloride depth testing and carbonation assessment; include Structural Engineer in site walkthrough to evaluate existing concrete condition. |
Spalled or delaminated concrete identified? Delaminated concrete that sounds hollow on hammer tap indicates loss of bond and often active corrosion beneath the surface. On balconies and elevated slabs, this creates both structural and life-safety concerns. | High | Action Perform sounding survey; commission repair scope prior to design; factor remediation into project budget and schedule. |
Steel connections and embeds inspected for corrosion? Embedded steel plates, angle clips, and connection hardware in coastal environments corrode faster than the surrounding concrete. These elements are typically hidden and discovered when work is opened up. | High | Action Open selective locations for visual inspection; include contingency in scope for connection replacement. |
Drainage and waterproofing failures identified? Ponding water, failed slope-to-drain, and compromised waterproofing membranes are common contributors to accelerated concrete deterioration. They also signal potential structural concern if slabs have been saturated for extended periods. | Medium | Action Review drainage performance during or after rain; probe membrane condition; assess slab condition at known ponding areas. |
Florida SB 4-D milestone inspection status confirmed? Senate Bill 4-D established mandatory Milestone Inspections for condominium and cooperative buildings three stories or higher. Projects involving existing buildings must understand the milestone inspection status and its implications for proposed work. | High | Action Confirm whether the building is subject to SB 4-D; obtain the most recent milestone inspection report; identify any Phase 2 findings that affect the project scope. |
Mechanical and utility penetrations previously made without structural review? Unauthorized penetrations through structural slabs, beams, or walls are found frequently in existing Florida multifamily buildings. These range from isolated MEP sleeves to large openings cut through post-tensioned members. | High | Action Inspect existing penetrations; compare to structural drawings; engage Structural Engineer to evaluate conditions that appear unauthorized. |
Balcony and elevated walkway conditions assessed? Balconies represent one of the highest-risk deferred maintenance categories in Florida coastal construction. Exposure, drainage, and limited redundancy make them a priority inspection item on any existing-building project. | High | Action Commission dedicated balcony structural assessment; document findings before project scope is finalized. |
Item | Risk Level | Recommended Action |
|---|---|---|
Existing fenestration product approvals on record? Florida requires product approval for windows and doors installed in buildings subject to Florida Building Code wind load requirements. Existing installations may predate the current approval program and may not meet current design pressures. | High | Action Request Florida Product Approval documentation for existing fenestration; verify design pressures against current FBC requirements for the site. |
Cladding attachment conditions inspected? Cladding panels, precast elements, and curtainwall systems attach to the structural frame through embedded connections or post-installed anchors. In older buildings, these may be corroded, undocumented, or not designed for current wind loads. | High | Action Open selective locations to inspect existing cladding connections; evaluate against current wind load requirements; document findings for Structural Engineer review. |
Differential movement between structure and envelope accommodated? Concrete frames in Florida move from thermal cycling, creep, and elastic deformation. Envelope systems attached to these frames must accommodate movement without transferring stress to the cladding or creating water infiltration pathways. | Medium | Action Review existing envelope details for movement joints; engage Structural Engineer to quantify expected movement at attachment points for replacement or new systems. |
Water infiltration history documented? Active or historic water infiltration traces the path of envelope system failures. It also indicates areas of elevated structural risk. Concrete that has been persistently wet is concrete whose reinforcement may be actively corroding. | High | Action Interview building management; review maintenance records; commission infrared thermography or moisture mapping if history is unclear. |
Roof-to-wall and parapet transitions detailed correctly? The intersection of the roofing system, wall assembly, and parapet is one of the most failure-prone locations in Florida commercial and multifamily construction. Improper detailing allows water to penetrate behind cladding and into structural elements. | Medium | Action Inspect existing conditions at all roof-to-wall transitions; document and photograph; include remediation in scope if deficiencies are found. |
Sealant joints assessed for age and condition? Sealant at curtainwall, storefront, and expansion joints has a finite service life. In Florida’s UV and thermal environment, sealant systems degrade faster than in temperate climates. Failed sealant is the most common entry point for wind-driven rain. | Medium | Action Visual assessment of all accessible sealant joints; probe condition with tool; estimate remaining service life; include recaulking or replacement in scope as appropriate. |
New envelope system anchorage designed against structural drawing? Replacement fenestration and cladding systems require anchor designs that reference substrate capacity. Slab edge geometry, concrete strength, and existing embedments all affect what is achievable. | High | Action Engage Structural Engineer to review anchorage design against field-verified conditions; confirm pull-test protocol if post-installed anchors are specified. |
Item | Risk Level | Recommended Action |
|---|---|---|
Does the project trigger Threshold Building requirements? Under Florida Statute §553.71, any building over three stories or 50 feet in height, or with an assembly occupancy space over 5,000 sq. ft. and 500 persons or more, is a threshold building requiring a Special Inspector for structural systems. This obligation attaches to the building type, not just to new construction. | High | Action Confirm building classification; if threshold, engage Special Inspector early and confirm Statement of Special Inspections is project-specific and complete. |
Construction value threshold for substantial improvement confirmed? In FEMA Special Flood Hazard Areas, improvements that equal or exceed 50% of the building’s market value trigger Substantial Improvement requirements, including bringing the structure into current flood zone compliance. | High | Action Determine whether the project is in a SFHA; calculate cumulative improvement value against current assessed market value; consult with the local floodplain administrator before finalizing scope. |
Change of occupancy classification evaluated? A change in occupancy classification, including an intensification of use within the same category, can trigger full structural re-evaluation for the new occupancy’s design loads and code requirements. | High | Action Confirm proposed vs. existing occupancy classification with structural and code consultant prior to programming; evaluate structural implications of any change. |
Florida High-Velocity Hurricane Zone (HVHZ) applicability confirmed? Broward and Miami-Dade counties fall within the HVHZ, which imposes stricter building product requirements, testing protocols, and NOA (Notice of Acceptance) requirements in addition to state-level Florida Product Approval. | High | Action Confirm project location relative to HVHZ boundary; if within, verify that all specified envelope products carry current NOA approval from Miami-Dade or Broward County. |
Fenestration special inspection requirement under Binding Interpretation #318 identified? For threshold buildings, Florida Binding Interpretation #318 clarifies that certain fenestration system installations require Special Inspection under FBC §110.8.1. This obligation must be reflected in both the specifications and the Statement of Special Inspections. | Medium | Action Review threshold building status; if applicable, confirm Special Inspection scope includes fenestration anchor installation with 48-hour advance notification to Inspector required. |
Historic designation evaluated for structural review requirements? Florida historic structures may be subject to alternative compliance pathways under the FBC, but structural modifications still require engineering evaluation. Historic designation can constrain repair methods and material choices in ways that affect structural performance. | Medium | Action Confirm local historic designation status; engage Structural Engineer early to identify acceptable repair strategies that meet both structural and preservation requirements. |
Structural Special Inspections scope included in permit documents? The Statement of Special Inspections must be submitted with the permit application on threshold building projects. Omission delays permit issuance; a vague or incomplete Statement creates field disputes and potential non-conformance conditions during construction. | High | Action Prepare project-specific Statement of Special Inspections during design development. Review with Special Inspector and EOR before finalizing. |
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This resource is published for informational purposes and does not constitute engineering advice. Consult a licensed Structural Engineer for project-specific guidance.
