Retail Store Build-Out: 205 Issues Found in Commercial Construction
AI plan review of a retail store construction project uncovered 205 issues—including 45 critical violations affecting fire protection, plumbing cross-connections, structural connections, electrical coordination, and code compliance before permit submission.
The Project
A retail store construction project involving a new commercial build-out with extensive coordination requirements across architectural, structural, mechanical, electrical, plumbing, and fire protection disciplines. The project required strict code compliance with 2021 IBC, 2021 IFC, 2018 IMC, and 2018 IPC standards.
Critical Findings (31)
Prohibited Cross-Connection at Yard Hydrant Installation
The drawing details a 'Non-Freeze Yard Hydrant' (Woodford S3) installed with a 'drain hole' buried in a gravel 'drain field' (weep hole) to allow drainage into the soil. This installation creates a submerged cross-connection that allows groundwater or soil contaminants to enter the potable water supply system through the open drain port when the hydrant is off and a negative pressure event occurs or via diffusion. While the building service entry has a backflow preventer (RPZ), the yard hydrant connection is downstream of this device, meaning any contamination introduced by the yard hydrant will contaminate the building's internal potable water distribution system, putting occupants at risk.
Missing Fire Rating Specification for Doors in 2-Hour Rated Walls
The floor plan explicitly labels the north and south exterior walls as '2 HOUR FIRE RATED WALL'. Door A (Overhead Delivery Door) and Door J (Service Door) are located within these 2-hour rated walls. However, the Door Schedule identifies Door A only as a 'STEEL OVERHEAD ROLL-UP' and Door J as 'HOLLOW METAL' without specifying the required fire-protection rating (e.g., 1.5 Hour, labeled). Standard roll-up doors and hollow metal doors are not inherently fire-rated. Installing non-rated opening protectives in a fire-resistance-rated assembly violates the integrity of the fire barrier.
Unprotected Expansion Joint in 2-Hour Fire-Resistance-Rated Wall
The floor plan designates the exterior perimeter walls as a '2 HOUR FIRE RATED WALL' and identifies 'EXPANSION JOINTS (TYPICAL)' within these walls. Detail 5 (Expansion Joint Detail) depicts this joint condition using only 'ELASTOMERIC SEALANT WITH NEOPRENE BACKER ROD' and a 'RUBBER CONTROL JOINT'. The detail fails to specify a fire-resistance-rated joint system (e.g., a listed firestop system) as required to maintain the 2-hour rating of the wall assembly. Standard elastomeric sealant and rubber components do not provide 2-hour fire resistance, creating a breach in the required fire barrier.
Missing Secondary (Emergency) Overflow Drainage at Roof Edge
Detail 7 (Roof Edge Detail at Low Side) depicts the primary drainage system consisting of a leader box and downspout through the parapet wall. However, the detail fails to show a secondary (emergency) overflow scupper or drain 2 inches above the low point, which is required by code when the perimeter construction extends above the roof. Without a separate overflow path, a blockage in the primary downspout could lead to structural overload or water intrusion.
Insufficient Holding Capacity for Stone Veneer Support
The drawing specifies a support bracket with a holding capacity of only 5 lbs/LF for a stone watertable/sill. Stone masonry is a heavy material, and a projecting watertable unit would typically weigh significantly more than 5 lbs/LF (likely >20 lbs/LF for solid stone/cast stone). This specification fails to design for the actual superimposed loads.
Rigid Vertical Connection in Exterior Bypass Framing
The details depict exterior cold-formed steel studs bypassing the roof structure and attached using 'STIFFCLIP LB' (rigid brackets) with a note stating 'PINS SHALL BE INSTALLED IN ALL HOLES'. This creates a rigid vertical connection between the roof structure and the non-load-bearing curtain wall studs. IBC 1604.3 requires structural systems to limit deflections and accommodate movements. A rigid connection forces the studs to act as load-bearing elements supporting the roof, attracting axial loads they are likely not designed for, leading to potential buckling or failure under roof live/snow loads.
Undersized Duct Package Capacity
The 'Package Ductwork Notes' state that the duct package is designed to handle a maximum of 2400 CFM. However, the Rooftop Unit Schedule specifies RTU-1 and RTU-2 as 10-ton units requiring 4000 CFM each. Installing 4000 CFM equipment on a duct system designed for 2400 CFM violates IMC 603.2 regarding proper duct sizing and will likely result in excessive static pressure, noise, and equipment performance issues.
Code Violation: Prohibited Direct Connection and Double Trapping
The drawing explicitly requires the condensate indirect waste line to be 'TRAPPED' and connected to the 'HOUSE SIDE OF ACTIVE TRAP'. This creates two simultaneous code violations: 1. Connecting a trapped line upstream of another active trap creates a prohibited 'double trap' condition (IPC 1002.1). 2. Condensate (clear-water waste) is required to discharge through an air gap into a waste receptor (indirect connection) per IPC 802.1 and 802.3. Connecting to the 'house side' of a trap is a direct connection method that bypasses the required air gap.
Fan Speed Controller Mounting Height Violates Accessibility/Code
The 'Ceiling Fan Notes' state that the manual fan speed controller must be mounted 'next to the thermostats.' The 'Power Schedule' specifies that thermostats are to be wall-mounted 'above electrical panels' at '9'-0" A.F.F. MAX.' Placing a manual fan control switch at 9 feet above the finished floor renders it inaccessible to occupants and violates accessibility requirements for controls (typically max 48"). It also effectively prevents the use of the fans without a ladder, creating a safety and operational hazard.
Missing Fall Protection Guard at Roof Hydrant
The roof plan shows a 'ROOF HYDRANT' located immediately adjacent to the roof edge (East side). Accessing this hydrant for firefighting operations establishes a walking surface at the edge of the roof. IFC Section 1015.2 requires guards along open-sided walking surfaces located within 36 inches of the edge. The provided 'ROOF EDGE DETAIL' (Detail 4) shows a low-profile fascia cover (approx. 5.5 inches vertical face) which does not meet the minimum 42-inch height requirement for guards specified in IFC Section 1015.3. While a note explicitly calls for a 'SAFETY RAIL SYSTEM' at the roof hatch, no such protection is indicated for the roof hydrant.
Uncoordinated Fire Service Riser Location in Restroom
The Fire Protection Site Plan (FP1) depicts the fire service line ('6" D.I.P.') entering the building at the northeast corner, which corresponds to the location of the Restroom shown on the Plumbing plans. However, the detailed Restroom Water Plan (P-2) does not show the required 4" fire riser, valve assembly, or associated clearances in this room. The restroom plan only accounts for the 1" domestic water service, creating a spatial conflict where the fire riser appears to clash with the restroom layout.
Conflicting Roof Drainage Discharge Method (Surface vs. Underground)
There is a direct contradiction regarding the storm water discharge method for the building's roof leaders. The Architectural Rainwater Calculations (A-6, Detail 3) explicitly state that roof leaders will flow under the sidewalk and discharge over the parking lot (surface flow). However, the Civil Grading & Drainage Plan (Sheet 16) and Downspout Detail show the roof leaders (RAL) hard-piped directly into the underground storm drainage system via cleanouts and 12" PVC pipes.
Conflict in Domestic Water Service Line Size (1" vs 2")
The Civil Utility Plan specifies a 2-inch commercial water service line connecting to the building. However, the Plumbing Water Riser and Restroom Water Plan explicitly depict and label the incoming water service line as 1-inch.
Lighting Control Panel Mounting Height Violation
Detail 3 shows the 'Lighting Contactor Enclosure' mounted above Panels 'A' and 'B'. The vertical dimension string indicates the top of the lower panels is at 6'-2" above the finished floor, with a 6" gap above them, placing the bottom of the Lighting Contactor Enclosure at 6'-8" (80") AFF. The enclosure is 23.5" tall, placing its center at approximately 7'-8" AFF. This violates NFPA 70 (NEC) Article 404.8(A), which limits the height of the center of the grip of the operating handle of any switch or circuit breaker to 6'-7" (2.0 m). IMC 301.10 mandates that electrical controls comply with NFPA 70.
Accessible Restroom Door Swing and Clearance Conflict
The single-user restrooms ('M' and 'W') feature in-swinging doors. Based on the visual scale relative to the 3'-0" doors (referenced in Schedule), the room depth appears insufficient to accommodate the door swing without overlapping the required fixture clearances (e.g., 60-inch depth for the water closet) or violating the requirement that doors not swing into fixture clearances.
Sample High Priority Findings (5 Total)
Missing Drainage for RPZ Backflow Preventer
The plumbing riser detail specifies a Reduced Pressure Zone (RPZ) backflow preventer inside the building, but the drawings do not show the required drainage connection. RPZ assemblies discharge water from the relief valve and require a direct connection to the sanitary drainage system (typically via an air gap to a floor drain) per IPC 301.3 to prevent flooding and damage.
Single-user toilet rooms labeled MEN/WOMEN instead of all-gender identification
The restroom plan shows two separate single-occupant toilet rooms (each containing a single set of fixtures) labeled for sex as 'MEN' and 'WOMEN.' IBC 2021 requires single-user toilet rooms to be identified as available for use by all persons regardless of sex, so the current labeling/signage intent conflicts with IBC requirements for single-user toilet rooms.
Detail shows 2% minimum grade slope at foundation; IBC requires 5% for ground adjacent to foundation
Detail shows 2% minimum grade slope at foundation; IBC requires 5% for ground adjacent to foundation. The exterior wall base detail calls for 'SLOPE GRADE 2% MIN.' at the building perimeter. IBC 2021 requires the ground immediately adjacent to the foundation to be sloped away from the building at not less than 5% for at least 10 feet (unless an approved alternative method is used where obstructions/lot lines prevent 10 feet, or other listed exceptions apply). The drawing's 2% grade slope for ground adjacent to the foundation is therefore a direct conflict with the prescriptive 5% requirement.
Roof hatch handrail/safety post heights shown below 42 in minimum guard height
The roof hatch access detail calls out a 'HANDRAIL AND ACCESS SYSTEM' at 3'-2" (38 inches) and ladder safety posts extending 30 inches minimum above the scuttle opening. Where a guard is required at an open-sided walking surface/opening with a drop greater than 30 inches, the IFC requires the guard height to be not less than 42 inches. The shown handrail/guard heights are below the 42-inch minimum.
Missing Thermal Barrier Separation for Foam Plastic Roof Insulation
Detail 7 shows 'INSULATION BOARD' (typically foam plastic) located above the roof structure. Detail 6 identifies the roof deck as '3/4" FIRE RETARDANT PLYWOOD DECK' with a plenum space below. Code Section 2603.4 requires foam plastic to be separated from the interior of a building (including concealed plenum spaces) by an approved thermal barrier of 1/2-inch gypsum wallboard or equivalent. Plywood is not listed as a compliant thermal barrier in Section 2603.4, and the provided code text does not contain an exception for roof covering assemblies regarding the thermal barrier requirement.
Value Delivered
"Finding 205 issues before permit submission prevented months of back-and-forth with the city. The cross-connection violation alone would have been a health safety disaster, and the fire rating gaps would have failed inspection immediately."
— Project Team