Commercial / Retail Plan Review: 61 Issues Found

Summary: The drawing feeder schedule lists feeder tag 2500.4 with conductors and conduit size but does not list any value in the 'GROUND CONDUCTOR' column. The specification requires feeders and branch circuits to be provided with an appropriately sized insulated equipment grounding conductor whether specifically noted or not.

Why it matters: Omitting an equipment grounding conductor on a large feeder can prevent proper fault clearing and bonding, creating a life-safety shock/fire hazard and likely failing NEC/inspection requirements.

Suggested next step: Confirm whether 2500.4 is intended to be a feeder (requiring an insulated EGC per general notes) or service-entrance conductors. If it is a feeder, revise the feeder schedule/one-line to show the required equipment grounding conductor size and associated installation requirements.

RFI draft: Confirm whether 2500.4 is intended to be a feeder (requiring an insulated EGC per general notes) or service-entrance conductors. If it is a feeder, revise the feeder schedule/one-line to show the required equipment grounding conductor size and associated installation requirements.

Summary: The 'Fault Current Calculations' schedule on drawing E-301 indicates 1 conductor per phase for Point C (At 500 kVA Transformer) and Point E (At 3869-LDP-1). However, the Feeder Schedule on the same sheet specifies that the associated feeders consist of multiple parallel sets: feeder '800.3' has 2 sets (meaning 2 conductors per phase) and feeder...

Why it matters: Underestimating the available fault current is a severe safety risk, as it may lead to the installation of downstream equipment with an insufficient Ampere Interrupting Capacity (AIC) rating. Because the calculated fault current at Panel 1148 (Point G) is currently shown as 9,767 A, correcting the upstream impedance to reflect the actual...

Suggested next step: Please revise the Fault Current Calculations for Points C and E to use the correct number of parallel conductors per phase (2 and 5, respectively) to match the Feeder Schedule. Subsequently, verify that the 10,000 AIC rating of the downstream equipment (Panels 1255 and 1148) remains sufficient for the corrected higher available fault current,...

RFI draft: Please revise the Fault Current Calculations for Points C and E to use the correct number of parallel conductors per phase (2 and 5, respectively) to match the Feeder Schedule. Subsequently, verify that the 10,000 AIC rating of the downstream equipment (Panels 1255 and 1148) remains sufficient...

Summary: Power Note 24 directs the contractor to install electrical boxes and fixtures per 'IBC SECTIONS 713.3.2 AND 713.4.1.2 FOR MINIMUM MEMBRANE PENETRATION PROTECTION REQUIREMENTS.' However, in the 2024 IBC, Section 713 governs shaft enclosures, not membrane penetrations. Section 714.1 explicitly states it governs 'the materials and methods of...

Why it matters: Referencing incorrect code sections could lead to non-compliant electrical box installations in fire-rated assemblies. A plan reviewer or building official will likely flag the incorrect code references, causing permitting delays. During construction, contractors following the wrong sections (shaft enclosure provisions instead of penetration...

Suggested next step: Request the electrical engineer correct Power Note 24 to reference the appropriate 2024 IBC Section 714 provisions for membrane penetration protection (e.g., Section 714.4.2 for membrane penetrations of fire-resistance-rated walls) instead of the currently referenced Sections 713.3.2 and 713.4.1.2, which pertain to shaft enclosures.

RFI draft: Request the electrical engineer correct Power Note 24 to reference the appropriate 2024 IBC Section 714 provisions for membrane penetration protection (e.g., Section 714.4.2 for membrane penetrations of fire-resistance-rated walls) instead of the currently referenced Sections 713.3.2 and...

Summary: Mechanical Detail Note 10 specifies a CO2 sensor control sequence that directs the RTU outdoor air (OA) damper to 'MODULATE TOWARDS FULLY CLOSED WHEN LEVELS ARE BELOW 800 PPM.' The control sequence does not specify a minimum OA damper position. IEBC Section 807.2 requires that altered existing mechanical ventilation systems 'shall provide not...

Why it matters: This conflict could lead to a plan review rejection or inspection failure during commissioning. If the controls are installed as specified, the OA damper could close fully during periods of low CO2 (e.g., early morning pre-occupancy or lightly occupied periods), providing zero outdoor air to occupied spaces in violation of IEBC 807.2. The...

Suggested next step: Please clarify the CO2 demand control ventilation sequence specified in Detail Note 10. As written, the OA damper is directed to modulate towards fully closed when CO2 levels are below 800 PPM, which could reduce outdoor air below the minimum 5 cfm/person required by IEBC Section 807.2. Please specify a minimum OA damper position in the CO2...

RFI draft: Please clarify the CO2 demand control ventilation sequence specified in Detail Note 10. As written, the OA damper is directed to modulate towards fully closed when CO2 levels are below 800 PPM, which could reduce outdoor air below the minimum 5 cfm/person required by IEBC Section 807.2. Please...

Summary: The drawing's Piping Insulation Table specifies minimum insulation thicknesses for refrigerant hot gas lines as 1.0' for pipes up to 1' and 1.5' for pipes 1-1/2' to 8'. Refrigerant hot gas (compressor discharge) lines inherently operate at fluid temperatures well above 140°F, placing them in at least the 141–200°F row of IECC Table C403.12.3....

Why it matters: Insufficient insulation on high-temperature refrigerant piping results in increased energy loss, reduced system efficiency, and potential surface temperature safety concerns. This discrepancy would likely be identified during plan review or field inspection, causing permitting delays or requiring costly rework of already-installed insulation.

Suggested next step: Request that the engineer revise the Piping Insulation Table to increase refrigerant hot gas line insulation thicknesses to comply with IECC Table C403.12.3 for the applicable fluid operating temperature range (141–200°F minimum). Specifically, increase insulation from 1.0' to at least 1.5' for pipes up to 1' and from 1.5' to at least 2.0' for...

RFI draft: Request that the engineer revise the Piping Insulation Table to increase refrigerant hot gas line insulation thicknesses to comply with IECC Table C403.12.3 for the applicable fluid operating temperature range (141–200°F minimum). Specifically, increase insulation from 1.0' to at least 1.5' for...

Summary: The submitted COMcheck compliance documentation identifies the project energy code as the “2022/2025 Denver Energy Code.” The governing requirements for this review are the 2021 International Energy Conservation Code, which requires commercial buildings to comply with the IECC commercial provisions. A compliance certificate prepared for a...

Why it matters: This can trigger plan review rejection and resubmittal of the energy compliance documentation, delaying permit issuance and potentially requiring redesign if the 2021 IECC requirements differ from the referenced local code.

Suggested next step: Confirm the applicable energy code for the permit. If the 2021 IECC governs, revise/resubmit the COMcheck (or other approved compliance documentation) using the 2021 IECC basis and ensure the submitted certificate matches the code under which the project is being reviewed.

RFI draft: Confirm the applicable energy code for the permit. If the 2021 IECC governs, revise/resubmit the COMcheck (or other approved compliance documentation) using the 2021 IECC basis and ensure the submitted certificate matches the code under which the project is being reviewed.

Summary: The main floor corridor serving as the egress path between private offices, Conference Room (107), Huddle Rooms (105-106), and the open office/exits does not show any emergency battery-equipped lighting fixtures. Per the luminaire schedule, only fixture types AE (HIGH BAY WITH EMERGENCY BATTERY BACKUP) and (R2) (RELOCATED LINEAR PENDANT WITH...

Why it matters: Without emergency illumination in the corridor, building occupants exiting from private offices, Conference Room, and Huddle Rooms during a power failure would traverse an unlit egress corridor to reach exit doors. Exit signs alone do not provide adequate walking-surface illumination. This life safety violation will likely result in plan review...

Suggested next step: Request the electrical engineer to confirm whether emergency illumination is provided in the corridor per IFC 1008.3. If not, request that emergency battery-equipped fixtures (such as type AE or (R2) with battery packs per the luminaire schedule Special Notes 2 and 3), standalone emergency light units, or corridor fixture battery pack...

RFI draft: Request the electrical engineer to confirm whether emergency illumination is provided in the corridor per IFC 1008.3. If not, request that emergency battery-equipped fixtures (such as type AE or (R2) with battery packs per the luminaire schedule Special Notes 2 and 3), standalone emergency light...

Summary: Drawing note D.10 specifies two distinct options for field-installed refrigerant copper tubing joints: Type K hard-drawn copper with 'WROUGHT COPPER SILVER SOLDERED FITTINGS AND COUPLINGS' and Type L ACR copper with 'BRAZED JOINTS.' The use of two different terms — 'silver soldered' versus 'brazed' — within the same specification implies two...

Why it matters: Common refrigerants such as R-410A operate at high-side condensing pressures of 350–400 psi, far exceeding the 200 psi threshold for permissible solder joints. If a contractor interprets 'silver soldered' literally as a soldering process and applies it to the high-pressure side of a refrigerant system, the joints could be structurally...

Suggested next step: Clarify whether 'silver soldered' in note D.10 is intended to mean brazing with silver-based filler metal per AWS A5.8 and IMC Section 1108.3.1 requirements. If so, revise the note to use the term 'brazed' consistently for both the Type K and Type L copper tubing options to align with IMC terminology. If actual soldering per IMC Section...

RFI draft: Clarify whether 'silver soldered' in note D.10 is intended to mean brazing with silver-based filler metal per AWS A5.8 and IMC Section 1108.3.1 requirements. If so, revise the note to use the term 'brazed' consistently for both the Type K and Type L copper tubing options to align with IMC...

Summary: The Suspended Electric Water Heater Detail (Detail D) shows the water heater suspended from structure above in a plenum-rated location above the ceiling. The P&T relief valve discharge terminates at a 2' funnel fitting with a 1.5' air gap in this concealed space, which is not readily visible and observable by building occupants. IMC Section...

Why it matters: This would be flagged during plan review or mechanical inspection because the code intends for building occupants to be alerted (via alarm) when a relief valve activates, indicating a potentially dangerous overpressure or overheating condition. An automatic shut-off valve alone could mask this hazardous condition by silently stopping water flow...

Suggested next step: Request the engineer clarify and revise Detail D to include a leak detection monitoring device with alarm notification at the P&T valve discharge location in compliance with IMC Section 1006.6, Item 7. Confirm whether the Floodmaster RS-094 automatic shut-off valve should be replaced with an alarm-only leak detection device, or if a separate...

RFI draft: Request the engineer clarify and revise Detail D to include a leak detection monitoring device with alarm notification at the P&T valve discharge location in compliance with IMC Section 1006.6, Item 7. Confirm whether the Floodmaster RS-094 automatic shut-off valve should be replaced with an...

Summary: Mechanical Detail Note 10 specifies a CO2-based control sequence that directs the RTU outdoor air damper to 'MODULATE TOWARDS FULLY CLOSED WHEN LEVELS ARE BELOW 800 PPM.' This control sequence does not specify a minimum outdoor air damper position to ensure the required minimum outdoor airflow rates are maintained. The ventilation schedule on...

Why it matters: During periods of low occupancy when CO2 levels drop below 800 PPM, the OA damper would close toward the fully closed position, potentially reducing or eliminating the minimum ventilation airflow required by Section 403.3 and the project's own ventilation rate calculations. This would result in a code compliance failure during plan review and...

Suggested next step: Request the mechanical engineer revise the CO2 demand control ventilation sequence in Note 10 to include a minimum outdoor air damper position that maintains the code-required minimum outdoor airflow rate (Voz) per the ventilation schedule during all occupied conditions, in compliance with Section 405.1 of the 2024 IMC. The revised note should...

RFI draft: Request the mechanical engineer revise the CO2 demand control ventilation sequence in Note 10 to include a minimum outdoor air damper position that maintains the code-required minimum outdoor airflow rate (Voz) per the ventilation schedule during all occupied conditions, in compliance with...

Summary: Drawing note 59.E specifies that duct smoke detectors, when connected to the fire alarm system, shall be connected 'as trouble alarm.' However, IMC Section 606.4.1 explicitly requires that duct smoke detector actuation 'shall activate a visible and audible supervisory signal at a constantly attended location' and that 'duct smoke detectors...

Why it matters: This mislabeling would result in incorrect fire alarm panel programming. A trouble signal indicates a system fault (e.g., wiring issue), while a supervisory signal indicates an abnormal condition requiring investigation (e.g., smoke detection). Monitoring stations have different dispatch and response protocols for each. If programmed as trouble...

Suggested next step: Request the engineer revise Note 59.E to specify that duct smoke detectors shall be connected to the fire alarm system as a 'supervisory signal' rather than a 'trouble alarm,' in compliance with IMC Section 606.4.1. Confirm that fire alarm contractor shop drawings and sequence of operation reflect the supervisory signal classification for all...

RFI draft: Request the engineer revise Note 59.E to specify that duct smoke detectors shall be connected to the fire alarm system as a 'supervisory signal' rather than a 'trouble alarm,' in compliance with IMC Section 606.4.1. Confirm that fire alarm contractor shop drawings and sequence of operation...

Summary: The general notes state that existing flexible ductwork may be reused if it has a UL 181 tag. IMC requires that materials, equipment and devices are not reused unless they are in good working condition and approved. The drawing note’s reuse condition is based on labeling only and does not require approval.

Why it matters: If existing flexible ductwork is reused based on labeling alone, it can be rejected during inspection for lack of required approval, forcing removal/replacement after installation and causing schedule delays and added cost.

Suggested next step: Please revise the general note on reusing existing flexible ductwork to state reuse is permitted only where the existing duct is in good working condition and is approved by the code official (otherwise replace). Confirm the intended acceptance/approval process for any reused flexible ductwork.

RFI draft: Please revise the general note on reusing existing flexible ductwork to state reuse is permitted only where the existing duct is in good working condition and is approved by the code official (otherwise replace). Confirm the intended acceptance/approval process for any reused flexible ductwork.

Summary: The Suspended Electric Water Heater Detail (Detail D) on sheet M-002 specifies 'PIPE 1-1/4' DRAIN TO OPEN-SITE AT NEAREST FLOOR DRAIN OR SERVICE SINK WITH 1' AIR GAP.' The pan drain is an indirect waste pipe (per IPC 504.7.1, the pan shall be drained by an indirect waste pipe). IPC 802.3.1 requires the air gap between an indirect waste pipe and...

Why it matters: An undersized air gap on the drain pan indirect waste pipe could allow contaminated drainage water to back up into the pan and potentially contact the water heater, defeating the purpose of the indirect connection. This would be flagged during plumbing plan review or field inspection, causing a correction order that delays approval and requires...

Suggested next step: Please revise the drain pan discharge air gap in the Suspended Electric Water Heater Detail (Detail D) from 1' to not less than 2-1/2' (two times the 1-1/4' drain pipe diameter) to comply with IPC Section 802.3.1. Confirm the termination arrangement at the floor drain or service sink will accommodate this dimension.

RFI draft: Please revise the drain pan discharge air gap in the Suspended Electric Water Heater Detail (Detail D) from 1' to not less than 2-1/2' (two times the 1-1/4' drain pipe diameter) to comply with IPC Section 802.3.1. Confirm the termination arrangement at the floor drain or service sink will...

Summary: The sheet’s plumbing fixture calculations and provided fixture counts are explicitly based on “TABLE 2902.1” rather than the 2024 IPC basis for minimum plumbing facilities. The 2024 IPC requires that the minimum number of fixtures be provided per IPC Table 403.1; using a different table as the stated design basis is a direct code-basis...

Why it matters: Because the drawings document fixture compliance using a non-IPC table, the AHJ can reject the fixture count during plan review and require recalculation/revision, which can delay permitting and potentially require late changes to restroom layouts and plumbing rough-in if counts differ under IPC Table 403.1.

Suggested next step: Revise the plumbing fixture count analysis to demonstrate compliance with 2024 IPC Section 403.1 using IPC Table 403.1 (not IBC Table 2902.1), and confirm the provided quantities/fixture types still meet or exceed the IPC minimums for the actual uses shown.

RFI draft: Revise the plumbing fixture count analysis to demonstrate compliance with 2024 IPC Section 403.1 using IPC Table 403.1 (not IBC Table 2902.1), and confirm the provided quantities/fixture types still meet or exceed the IPC minimums for the actual uses shown.

Summary: Drawing Note 40 states that 'LIGHT SWITCHES SHALL BE MOUNTED 48' AFF TO CENTERLINE OF THE BOX'. However, Section 309.3 requires operable parts to be placed within the reach ranges specified in Section 308, and Section 308.2.1 establishes a maximum high forward reach of 48 inches. Because a light switch is an operable part and its toggle or...

Why it matters: Installing switch boxes with a 48-inch centerline is a common constructability error that leads to failed accessibility inspections. Correcting this after installation requires opening finished drywall, lowering the electrical boxes, potentially pulling new wire if slack is insufficient, and re-patching/painting the walls, causing significant...

Suggested next step: Please confirm if the mounting height for light switches should be revised to state '48 inches AFF to the highest operable part' or if the centerline height should be lowered (e.g., to 46 inches AFF) to ensure compliance with ADA maximum reach range requirements.

RFI draft: Please confirm if the mounting height for light switches should be revised to state '48 inches AFF to the highest operable part' or if the centerline height should be lowered (e.g., to 46 inches AFF) to ensure compliance with ADA maximum reach range requirements.