Aviation Hangar: 15 Issues Found

Summary: The project information identifies the building as Occupancy Group S-2. However, the roof framing plan repeatedly refers to the structure as a 'PREFAB HANGER' (hangar), and the location map confirms the building is situated at Sedona Airport among aircraft-related businesses including Guidance Air, Apex Air Tours, and AeroZone. Per IBC Section...

Why it matters: This misclassification has cascading impacts on code compliance. Group S-1 has more restrictive height, area, and fire protection requirements than S-2. Per IBC Section 412.1, aircraft-related occupancies must also comply with Sections 412.1 through 412.7 and the International Fire Code, which may impose additional requirements not addressed in...

Suggested next step: Revise the occupancy classification from Group S-2 to Group S-1 per IBC Section 311.2 to correctly reflect the aircraft hangar use. Verify all design elements comply with S-1 requirements, including Table 601 fire-resistance ratings for structural members and roof construction, Table 504.3 and 504.4 height and story limitations, Table 602...

RFI draft: Revise the occupancy classification from Group S-2 to Group S-1 per IBC Section 311.2 to correctly reflect the aircraft hangar use. Verify all design elements comply with S-1 requirements, including Table 601 fire-resistance ratings for structural members and roof construction, Table 504.3 and...

Summary: The one-line diagram shows the existing service as 'EXISTING 200 AMP, 120/240V, 1Ø, 3W, NEMA 3R METER, MAIN C/B WITH SERVICE BREAKER BRACE FOR 22,000 AIC.' However, both panel schedules designate the voltage as 120V, 1Ø, 2W. Panel HP1 shows 'VOLTAGE: 120V, 1ø, 2W' yet contains a '100A/2P MAIN C/B' and a '50/2P' breaker feeding Panel A. Panel A...

Why it matters: This discrepancy would cause the contractor to order the wrong panel equipment. A 120V, 2-wire panel cannot physically accept 2-pole breakers or serve 240V loads such as the overhead door opener. If the panels are ordered as specified (120V, 2W), the equipment would need to be returned and re-ordered as 120/240V, 3W panels, causing procurement...

Suggested next step: Request the engineer of record to confirm whether panels HP1 and Panel A should be designated as 120/240V, 1Ø, 3W to match the service configuration and the 2-pole breaker requirements shown in both panel schedules. If confirmed, update both panel schedules to show the correct voltage designation, add a neutral conductor to the feeder...

RFI draft: Request the engineer of record to confirm whether panels HP1 and Panel A should be designated as 120/240V, 1Ø, 3W to match the service configuration and the 2-pole breaker requirements shown in both panel schedules. If confirmed, update both panel schedules to show the correct voltage...

Summary: The One-Line Diagram identifies the 'MAXIMUM AVAILABLE FAULT CURRENT = 14,318 AMPS SYMM'. However, the panel schedules for both PANELBOARD HP1 and PANELBOARD A specify a 'MIN. A.I.C.: 10,000 AIC'. Installing electrical panels and breakers with an interrupting rating (10,000 Amps) that is lower than the available fault current (14,318 Amps)...

Why it matters: If a short circuit occurs, breakers rated at 10,000 AIC will not be able to safely interrupt the 14,318 amps of fault current. This can result in catastrophic failure, equipment explosion, arc flash injuries, and fire. The downstream panelboards must be properly rated for the fault current or protected by an approved series-rated combination.

Suggested next step: Please revise the panel schedules for Panel 'HP1' and Panel 'A' to specify a minimum AIC rating that meets or exceeds the available fault current of 14,318 AMPS (e.g., 22,000 AIC), or clearly denote an approved series rating combination on the drawings.

RFI draft: Please revise the panel schedules for Panel 'HP1' and Panel 'A' to specify a minimum AIC rating that meets or exceeds the available fault current of 14,318 AMPS (e.g., 22,000 AIC), or clearly denote an approved series rating combination on the drawings.

Summary: Detail F1.1 on sheet A1 specifies the exterior wall footing as 30' wide (DIM. A = 30') with 3 #4 bars and #3 ties at 24' OC, and a minimum 18' depth to undisturbed soil (DIM. C). Plan Note 1 on the same sheet specifies the exterior concrete footing as 14'×12' with only 2 #4 bars and #3 ties at 24' OC, minimum 12' into undisturbed soil. Both...

Why it matters: The contractor cannot proceed with footing excavation, formwork, or rebar placement without knowing which specification to follow. These dimensional and reinforcement differences directly affect structural capacity, material quantities, and excavation depth. A building inspector will flag the discrepancy, potentially halting the foundation...

Suggested next step: Clarify the correct exterior footing dimensions (width and depth), number of #4 continuous rebar, and minimum embedment depth to undisturbed soil. Update Detail F1.1 and Plan Note 1 to be consistent, or provide structural calculations confirming the intended design.

RFI draft: Clarify the correct exterior footing dimensions (width and depth), number of #4 continuous rebar, and minimum embedment depth to undisturbed soil. Update Detail F1.1 and Plan Note 1 to be consistent, or provide structural calculations confirming the intended design.

Summary: The Electrical One-Line Diagram includes a note: 'MAXIMUM AVAILABLE FAULT CURRENT = 14,318 AMPS SYMM'. Panel schedules for Panel HP1 and Panel A indicate 'MIN. A.I.C.: 10,000 AIC'. The drawings provided do not explicitly state that the 14,318A value is the available fault current at the line terminals of Panels HP1 and A, so the available fault...

Why it matters: Per NEC 110.9, equipment interrupting rating must not be less than the available fault current at the equipment’s line terminals. If the available fault current at Panel HP1 or Panel A exceeds 10kAIC, the specified minimum AIC would be insufficient and could present a severe safety hazard during a fault.

Suggested next step: Provide the available fault current (AFC) calculation/utility data at the line terminals of Panels HP1 and A. If AFC exceeds 10,000A, revise the panel (and/or main device) interrupting rating to meet or exceed the calculated AFC, or revise the design to reduce AFC (e.g., impedance/limiting device) as required.

RFI draft: Provide the available fault current (AFC) calculation/utility data at the line terminals of Panels HP1 and A. If AFC exceeds 10,000A, revise the panel (and/or main device) interrupting rating to meet or exceed the calculated AFC, or revise the design to reduce AFC (e.g., impedance/limiting...

Summary: 5 index entries | 1 perfect matches | 2 mismatched | 2 missing Mismatched (2): A2: Expected: SECTION, ELEVATION | Actual: Building Elevations and Section (p2) E-1.0: Expected: SEE ATTACHED ELECTRICAL CALCS & DRAWINGS | Actual: ELEC. ONE-LINE DIAGRAM - 'SES' (p3) Missing (2), listed in drawing index but not found in the...

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Suggested next step:

RFI draft: 📄 A1 Schedule Text: DRAWING INDEX, page 1

Summary: Specification Note 5 on this sheet directs the contractor to 'GROUT AND SEAL ALL CONDUIT PENETRATIONS OF WALLS AND FLOOR SLABS TO PRESERVE FIRE RATING AND WATERTIGHT INTEGRITY.' The note explicitly acknowledges fire-resistance-rated assemblies are being penetrated by its language 'to preserve fire rating.' However, Section 714.2 requires 'A...

Why it matters: A plan reviewer would flag this note as noncompliant with Section 714.2 because it does not reference any listed firestop system or acknowledge the specific conditions required by the exception. Section K104.2 also requires construction documents to indicate 'the materials and methods for maintaining required structural safety, fire-resistance...

Suggested next step: Request the engineer of record to revise Specification Note 5 to require UL-listed penetration firestop systems installed per the manufacturer's instructions and listing criteria as required by IBC Section 714.2. If the exception conditions of Section 714.4.1 are intended to be relied upon, the documents should explicitly identify the...

RFI draft: Request the engineer of record to revise Specification Note 5 to require UL-listed penetration firestop systems installed per the manufacturer's instructions and listing criteria as required by IBC Section 714.2. If the exception conditions of Section 714.4.1 are intended to be relied upon, the...

Summary: Plan Note 5 specifies the installation of a '3068' door. A 3068 door has a nominal size of 3'-0' wide by 6'-8' (80 inches) high. Because standard door frames include a stop that reduces the height of the opening (typically by 1/2' to 5/8'), and clearances must be accounted for at the floor finish or threshold, a nominal 80-inch door and frame...

Why it matters: Failing to meet the strict 80-inch clear height requirement in a means of egress is a critical violation that building inspectors consistently catch. If framed and installed as a 6'-8' opening, the door frame and surrounding wall finishes will likely need to be torn out and replaced with a taller assembly (such as a 7'-0' nominal door) to pass...

Suggested next step: Please confirm the required clear opening height for the new door referenced in Note 5. A standard 3068 (6'-8' nominal) door assembly will not provide the 80-inch minimum clear opening height mandated by IBC 1010.1.1 due to the door frame stop. Please advise if the specification should be revised to a 3070 (7'-0' nominal) door or another...

RFI draft: Please confirm the required clear opening height for the new door referenced in Note 5. A standard 3068 (6'-8' nominal) door assembly will not provide the 80-inch minimum clear opening height mandated by IBC 1010.1.1 due to the door frame stop. Please advise if the specification should be...

Summary: Plan Notes 2 and 6 specify constructing new non-bearing stud walls 'OVER EXST STEEL STRUCTUAL BUILDING FRAME' with '1/2' GYP BD EA SIDE'. Applying standard gypsum board to both sides of these perimeter wall assemblies places a layer of gypsum wallboard on the exterior surface (facing the existing unconditioned metal siding cavity). Section...

Why it matters: Standard gypsum wallboard used as an exterior surface layer will be exposed to humidity and condensation from the unconditioned wall cavity behind the existing metal siding, leading to degradation, mold growth, and failure of the board. Additionally, installing a back layer of board on surface-mounted hat channels (as specified in Note 2) is...

Suggested next step: Please revise Plan Notes 2 and 6 to either specify only one layer of gypsum board on the conditioned interior side of the perimeter framing, or specify an approved exterior-grade gypsum sheathing (compliant with ASTM C1177/C1280) for the cavity-facing side if a back layer is required. Additionally, clarify the intended assembly for the hat...

RFI draft: Please revise Plan Notes 2 and 6 to either specify only one layer of gypsum board on the conditioned interior side of the perimeter framing, or specify an approved exterior-grade gypsum sheathing (compliant with ASTM C1177/C1280) for the cavity-facing side if a back layer is required....

Summary: The drawing's Project Description item 2 states 'NEW PARTITIONS, DOORS @ STORAGE / OFFICE,' indicating office use is part of the project. However, the Corrections and Revisions section on the same sheet states 'A1, (REMOVAL OF OFFICE SPACE,' indicating office use was eliminated from Sheet A1. The drawing also lists 'OCCUPANCY GROUP S-2'...

Why it matters: This unresolved contradiction has significant code compliance implications under the 2018 IBC. If office use is included, the occupancy classification may need to address B-occupancy provisions, with additional requirements for egress, accessibility, ventilation, and energy code compliance for conditioned space. The partitioned room visible on...

Suggested next step: Request the design team to: (1) clarify whether the proposed use is storage-only or includes office space; (2) update the project description to match the intended use; (3) clearly label the intended use of the partitioned room on the floor plan; and (4) confirm the S-2 occupancy classification is appropriate for the final determined use.

RFI draft: Request the design team to: (1) clarify whether the proposed use is storage-only or includes office space; (2) update the project description to match the intended use; (3) clearly label the intended use of the partitioned room on the floor plan; and (4) confirm the S-2 occupancy classification...

Summary: Panel HP1 schedule states 'VOLTAGE: 120V, 1ø, 2W' and Panel A schedule states 'VOLTAGE: 120V, 1Ø, 2W.' However, the one-line diagram shows the service entrance is '200 AMP, 120/240V, 1Ø, 3W.' Panel HP1 has a 100A/2P main breaker and a 50/2P feeder breaker to Panel A. Panel A is shown with a 60/2P breaker on the one-line. Both panel schedules...

Why it matters: This voltage designation error will be flagged during electrical plan review. An inspector cannot approve panels labeled 120V, 2W that contain 2-pole breakers and show two-phase load distribution. Incorrect voltage labeling can lead to ordering wrong panel equipment, incorrect wire sizing, and improper load calculations. The panels should be...

Suggested next step: Confirm that the electrical system is 120/240V, 1Ø, 3W as indicated by the service entrance and one-line diagram, and correct both panel schedules (HP1 and Panel A) to reflect the proper voltage designation.

RFI draft: Confirm that the electrical system is 120/240V, 1Ø, 3W as indicated by the service entrance and one-line diagram, and correct both panel schedules (HP1 and Panel A) to reflect the proper voltage designation.

Summary: General Note C on sheet A1 states 'NO NEW EXTERIOR WORK AT ALL.' However, Plan Note 4 on the same sheet specifies 'EXISTING 24GA METAL SIDING - REPLACE WHERE WALL HT IS EXTENDED ABOVE ORIGINAL BUILDING,' and the project description states the scope includes 'RISE ROOF FRAMING OF (2) SIDE AREAS.' Replacing exterior metal siding and raising the...

Why it matters: A plan reviewer will flag this contradiction during permitting, as General Note C states no exterior modifications are proposed while the drawings clearly show roof raising and siding replacement. This could delay permit issuance until the discrepancy is resolved. During construction, the general note could also create contractual disputes...

Suggested next step: Clarify whether General Note C should be revised or removed, given that the project scope includes raising roof framing on both side areas and replacing exterior metal siding where wall heights are extended. Update the general notes to accurately reflect the scope of exterior work.

RFI draft: Clarify whether General Note C should be revised or removed, given that the project scope includes raising roof framing on both side areas and replacing exterior metal siding where wall heights are extended. Update the general notes to accurately reflect the scope of exterior work.

Summary: An electrical note states “NO CHANGES TO SERVICE OR PANELS REQUIRED UNDER THIS PERMIT.” However, the electrical plan explicitly labels “NEW PANEL 'A'”, and the Panelboard A schedule is explicitly labeled “(NEW PANEL)”. These statements directly conflict.

Why it matters: This creates an explicit permitting and construction scope conflict: a “new panel” is a panel change, but the notes state no panel changes are required under the permit. This can lead to permit denial, incorrect permit valuation/scope, or failed inspections if a panel is installed without being included in the permitted scope.

Suggested next step: Confirm whether Panel 'A' is being newly installed under this permit. If yes, revise the note stating no panel changes; if no, revise the plan and schedule to remove “NEW PANEL 'A'” / “(NEW PANEL)” and clarify the actual electrical scope.

RFI draft: Confirm whether Panel 'A' is being newly installed under this permit. If yes, revise the note stating no panel changes; if no, revise the plan and schedule to remove “NEW PANEL 'A'” / “(NEW PANEL)” and clarify the actual electrical scope.

Summary: The exterior building elevations do not indicate any address identification numbers for this new or existing building. IBC Section 502.1 requires all new and existing buildings to be provided with approved address identification that is legible, contrasts with the background, and is placed in a position visible from the street or road fronting...

Why it matters: Failing to provide address identification on the building exterior violates fire and life safety requirements, as it prevents emergency responders from easily locating the building during an incident. This omission will likely result in a failed final inspection by the fire marshal or building official, which can delay the issuance of the...

Suggested next step: Please update the building elevations to indicate the location and specifications of the address identification, ensuring characters are a minimum of 4 inches high with a 1/2-inch stroke width and contrast with their background, as required by IBC Section 502.1.

RFI draft: Please update the building elevations to indicate the location and specifications of the address identification, ensuring characters are a minimum of 4 inches high with a 1/2-inch stroke width and contrast with their background, as required by IBC Section 502.1.

Summary: The correction letter dictates to 'Show location of wall or floor mounted interior unit.' The electrical plan conflicts with this explicit directive by only showing the exterior 'MINI-SPLIT A/C COND. UNIT' and completely omitting the location of the indoor unit.

Why it matters: Failing to address the plan reviewer's directive will likely lead to the rejection of the permit resubmittal. Additionally, without a location for the interior unit on the plan, the electrical contractor cannot properly coordinate and rough-in the required power and control wiring between the outdoor condenser and the indoor unit.

Suggested next step: Please update the electrical floor plan to show the exact location of the wall or floor-mounted interior mini-split unit as requested by the correction letter. Ensure that any required power or control wiring pathways between the interior and exterior units are clearly indicated.

RFI draft: Please update the electrical floor plan to show the exact location of the wall or floor-mounted interior mini-split unit as requested by the correction letter. Ensure that any required power or control wiring pathways between the interior and exterior units are clearly indicated.