Plan Review: 191 Issues Found

Summary: In Section 2/S302, an HSS8x8x3/8 column is positioned 4 3/4" from the face of the 8" CMU wall. Because the column itself is 8" wide, its outer face is located 12 3/4" from the CMU wall face. However, the concrete ledge designated to support the column is dimensioned as only 9 3/8" wide. This physical discrepancy means the column and its 1/2"x10x10" embed plate overhang the concrete ledge by ove...

Why it matters: This geometric impossibility violates basic structural strength requirements (IBC 1604.2), as the column load cannot be safely transferred to the foundation wall. The embed plate cannot be properly placed on the ledge, and the outer headed studs will lack concrete cover or fall entirely outside t...

Suggested next step: Please review the placement of the HSS8x8 column in Section 2/S302 relative to the 9 3/8" concrete ledge. Advise if the concrete ledge needs to be extended, the column shifted closer to the wall, or a different support method provided to ensure full bearing and proper anchor e...

RFI draft: Please review the placement of the HSS8x8 column in Section 2/S302 relative to the 9 3/8" concrete ledge. Advise if the concrete ledge needs to be extended, the column shifted closer to the wall, or a different support method provided to ensure fu...

Summary: Details 3 and 10 specify steel embed plates with dimensions exactly matching the width/thickness of the concrete elements they are cast into. Detail 3 places a 12"x16" plate on a 12" thick edge of slab. Detail 10 places a 12"x12" plate on a 12" curb. Sizing the embed plate to match the nominal concrete dimension means the edges of the plate will have zero concrete cover. Furthermore, the 12" cu...

Why it matters: Zero concrete cover violates standard durability and fire-protection requirements (ACI 318), exposing the structural embed to rapid corrosion. Insufficient edge distance for headed studs severely compromises the concrete breakout strength under IBC 1909.1, violating the requirement to safely supp...

Suggested next step: Please revise the dimensions of the embed plates in Details 3 and 10 to be smaller than the supporting concrete elements (e.g., maximum 8" wide for a 12" curb or slab edge) to ensure adequate concrete cover, clearance from the rebar cages, and sufficient edge distances for the...

RFI draft: Please revise the dimensions of the embed plates in Details 3 and 10 to be smaller than the supporting concrete elements (e.g., maximum 8" wide for a 12" curb or slab edge) to ensure adequate concrete cover, clearance from the rebar cages, and suf...

Summary: Section 6 specifies that the W8x28 hoist beam is connected to the supporting concrete beams using "EXP. ANCHORS". Hoist beams are by definition subjected to dynamic, vibratory, and impact loads. Standard post-installed mechanical expansion anchors are generally prohibited by ACI 318 for applications involving cyclic fatigue or impact loads unless specifically tested and qualified for such condi...

Why it matters: Using unqualified expansion anchors to support a hoist system poses a severe life-safety risk, as the dynamic forces can trigger anchor pullout and cause the beam/hoist to collapse. This violates the IBC requirement to safely support all factored loads, including impact loads (IBC 1604.2).

Suggested next step: Please confirm the hoist beam connection. Mechanical expansion anchors should not be used for dynamic/impact loads. Consider revising the detail to utilize cast-in-place headed studs, through-bolting, or undercut anchors specifically qualified for fatigue and impact loading.

RFI draft: Please confirm the hoist beam connection. Mechanical expansion anchors should not be used for dynamic/impact loads. Consider revising the detail to utilize cast-in-place headed studs, through-bolting, or undercut anchors specifically qualified for...

Summary: Detail 8 utilizes a slip connection at the top of the wall utilizing steel angles to laterally brace the wall while leaving a gap to 'ALLOW FOR 1" DEFLECTION OF STRUCTURE'. A global note applying to this detail dictates 'THIS DETAIL IS ALSO TO BE USED WHERE CONCRETE WALLS GO UP TO DECK.' This slip connection provides out-of-plane lateral support but entirely lacks a direct, positive connection ...

Why it matters: Concrete walls generally provide vertical load bearing or lateral shear resistance. ASCE 7-10 Section 1.4.5 requires such structural walls to have a 'direct connection between the walls and the roof or floor construction.' Furthermore, Section 1.4.2 requires all parts of the lateral force-resisti...

Suggested next step: Confirm if the concrete walls referenced in the Detail 8 note act as part of the primary lateral force-resisting system (e.g., shear walls). If they provide lateral shear resistance, revise the detail to include a direct, positive anchorage connection capable of transferring i...

RFI draft: Confirm if the concrete walls referenced in the Detail 8 note act as part of the primary lateral force-resisting system (e.g., shear walls). If they provide lateral shear resistance, revise the detail to include a direct, positive anchorage connec...

Summary: Section 8 details a stacked column condition separated by a concrete slab. The drawing calls out a '16"x12"x3/4" BASE PLATE WITH (4)-1"ø A325 BOLTS' for the lower column, which acts as a cap plate anchoring it to the underside of the slab. The upper column has a field weld symbol at its base but no embedded plate or anchors are specified. There is no positive connection (e.g., through-bolting) ...

Why it matters: Without a continuous mechanical connection between the stacked columns, the structure relies entirely on the concrete slab to transfer concentrated loads, shear, and uplift, which could lead to failure during wind or seismic events. Furthermore, the improper use of A325 bolts as concrete anchors ...

Suggested next step: Please clarify the connection between the upper and lower columns in Section 8 to ensure a continuous load path. Should the upper column be welded to an embedded plate? Please confirm if the A325 bolts at the lower column are intended to be through-bolts connecting both column...

RFI draft: Please clarify the connection between the upper and lower columns in Section 8 to ensure a continuous load path. Should the upper column be welded to an embedded plate? Please confirm if the A325 bolts at the lower column are intended to be throug...

Summary: Sections 5/S502 and 8/S502 detail an "HSS8x8 PER PLAN" sloped steel beam supported by a concrete column's embed plate ("1/2"x18"x12" EMBED WITH (6)-3/4"øx8" HEADED STUDS"). The connection utilizes "(2)-L4x4x1/4" clip angles. However, the provided weld symbols ("3 SIDES 1/4" and "1/4") only specify welds connecting the vertical legs of the angles to the HSS beam. There are no welds or fasteners ...

Why it matters: The drawing specifically notes that the "TOP OF STEEL SLOPES BETWEEN CONCRETE COLUMNS", meaning gravity loads will inherently induce a horizontal thrust at the beam's support. ASCE 7-10 Section 1.4.4 mandates that a positive connection be provided to resist horizontal forces acting parallel to th...

Suggested next step: Provide the required weld sizes and extents to positively connect the horizontal legs of the (2)-L4x4x1/4 clip angles to the 1/2"x18"x12" embed plate, ensuring compliance with positive connection and load path requirements.

RFI draft: Provide the required weld sizes and extents to positively connect the horizontal legs of the (2)-L4x4x1/4 clip angles to the 1/2"x18"x12" embed plate, ensuring compliance with positive connection and load path requirements.

Summary: Detail 9 on sheet S512 shows a steel "BEAM PER PLAN" resting on a "1/2"x6"x10" BEARING PLATE" over an "8" CMU" wall, but lacks any weld connecting the beam to the plate. While the beam connects to the "SLAB PER PLAN" diaphragm via a welded "4"x6 1/2"x5/16" CONT. BENT PLATE", the supporting CMU wall is unanchored to that slab diaphragm since no dowels or anchors are detailed connecting the wall ...

Why it matters: ASCE 7-10 Section 1.4.4 requires a positive connection for beams either directly to their supports or through a diaphragm. If connected through a diaphragm, the supporting element (CMU wall) must also connect to that diaphragm. Detail 9 fails both paths, as the beam isn't welded to its bearing pl...

Suggested next step: Please revise Detail 9 to provide a positive connection (e.g., weld) between the steel beam and the bearing plate, and detail the required dowels to anchor the 8" CMU wall to the concrete slab diaphragm.

RFI draft: Please revise Detail 9 to provide a positive connection (e.g., weld) between the steel beam and the bearing plate, and detail the required dowels to anchor the 8" CMU wall to the concrete slab diaphragm.

Summary: Plan Note 5 on sheet S110A directs the reader to "FOR COLUMN SCHEDULE AND DETAILS REFER TO SHEET S200." However, sheet S110A visually depicts steel columns supported on concrete piers (e.g., "-W12X96\nP30") and includes a "STEEL BASE PLATE SCHEDULE". In direct contradiction, sheet S200 is titled "CONCRETE COLUMN SCHEDULE" and schedules reinforced concrete columns starting at Level 2 (e.g., "LEV...

Why it matters: A conflict between structural steel columns and reinforced concrete columns represents a fundamental discrepancy in the building's primary structural frame. If the columns are steel at the foundation level, the concrete column schedule on S200 cannot be applied without a major transition detail, ...

Suggested next step: Please clarify the primary structural system for the columns. Are the columns steel (as indicated by the base plate schedule and plan tags on S110A) or reinforced concrete (as indicated by the schedule and details on S200)? If they are steel, please provide the applicable stee...

RFI draft: Please clarify the primary structural system for the columns. Are the columns steel (as indicated by the base plate schedule and plan tags on S110A) or reinforced concrete (as indicated by the schedule and details on S200)? If they are steel, plea...

Summary: Plan Note 4 on S120A specifies a 29" deep concrete floor slab construction including a 5" slab and beams, and directs to S012 for reinforcement. S012 Detail 1 accordingly details a cast-in-place concrete slab and joist system with #4 main reinforcement. In direct contradiction, Plan Note 8 on the same sheet (S120A) specifies a 4 1/2" slab over a 2" composite metal deck with welded wire fabric. ...

Why it matters: Providing conflicting specifications for the primary floor structural system (cast-in-place concrete pan-joist vs. steel frame with composite metal deck) will cause major confusion for bidding, procurement, and construction. The applicable reinforcing details, member connections, and slab penetra...

Suggested next step: Please clarify the intended structural floor system for the Second Floor Area A. Confirm whether the floor is a cast-in-place concrete joist/beam system (as referenced in Plan Note 4 and S012) or a steel frame with composite metal deck (as indicated by the framing plan and Pla...

RFI draft: Please clarify the intended structural floor system for the Second Floor Area A. Confirm whether the floor is a cast-in-place concrete joist/beam system (as referenced in Plan Note 4 and S012) or a steel frame with composite metal deck (as indicat...

Summary: Plan Note 4 on S150B dictates that the floor construction consists of cast-in-place concrete beams (29" deep including a 5" slab). However, Plan Note 1 refers to S001-S013 for typical details, which includes S008. S008 provides details exclusively for structural steel framing (e.g., steel beams to steel columns). Additionally, S150B calls out structural steel members directly on the plan (e.g.,...

Why it matters: This fundamental discrepancy leaves the primary structural framing material and system ambiguous. The specified typical steel connections (S008) cannot be applied to a cast-in-place concrete floor system as described in Note 4. Proceeding without clarification will result in severe procurement er...

Suggested next step: Please clarify the primary structural framing system for the Fifth Floor (Area B). If the floor framing consists of structural steel, please revise Plan Note 4 which incorrectly specifies a 29" deep concrete beam system. If the floor is a cast-in-place concrete system, please ...

RFI draft: Please clarify the primary structural framing system for the Fifth Floor (Area B). If the floor framing consists of structural steel, please revise Plan Note 4 which incorrectly specifies a 29" deep concrete beam system. If the floor is a cast-in-...

Summary: The general "NOTES" on sheet S120A (Note 1) indicate a 6 1/2" normal weight slab with a top of slab elevation of 110'-0". This directly conflicts with multiple "PLAN NOTES" on the same sheet: Note 3 states the top of slab elevation is 120'-0"; Note 4 specifies a 5" slab with a 120'-0" elevation; and Note 8 specifies a 4 1/2" slab with a 120'-0" elevation. Furthermore, Section 11 on sheet S502 c...

Why it matters: A 10-foot discrepancy in the top of slab elevation and varying slab thickness requirements will cause severe coordination failures across all disciplines, particularly affecting structural steel detailing, concrete volume calculations, stair geometry, and architectural floor-to-floor heights.

Suggested next step: Please clarify the correct top of slab elevation (110'-0" or 120'-0") for the Second Floor Area A. Additionally, confirm the correct concrete slab thickness to be used, as the notes variously specify 6 1/2", 5", and 4 1/2" slabs.

RFI draft: Please clarify the correct top of slab elevation (110'-0" or 120'-0") for the Second Floor Area A. Additionally, confirm the correct concrete slab thickness to be used, as the notes variously specify 6 1/2", 5", and 4 1/2" slabs.

Summary: Plan S120B references Detail 5/S507 along the perimeter edge of the slab. The framing members at this edge on the plan are explicitly called out as steel hollow structural sections (e.g., 'HSS16X8X1/2'). However, the referenced Detail 5/S507 depicts a poured concrete beam with internal reinforcement bars ('BEAM PER PLAN AND SCHEDULE').

Why it matters: This contradiction between a steel HSS member and a poured concrete beam creates a major conflict for perimeter structural framing. This will impact steel fabrication, concrete formwork, and the installation details for the architectural handrail embed shown in the section.

Suggested next step: Please clarify the intended edge framing at the locations referencing Detail 5/S507 on S120B. Should the perimeter be framed with steel HSS members as shown on the plan, or a concrete beam as detailed in 5/S507? Provide updated details or plan notes to resolve the material dis...

RFI draft: Please clarify the intended edge framing at the locations referencing Detail 5/S507 on S120B. Should the perimeter be framed with steel HSS members as shown on the plan, or a concrete beam as detailed in 5/S507? Provide updated details or plan not...

Summary: The framing plan calls out Detail 11/S500 at grid Z.5. Within Detail 11/S500, the column is labeled as "HSS12x12 PER PLAN", and a nested detail "12/S500" is called out for the top beam connection. However, Detail 12/S500 illustrates this exact connection utilizing a "W27 COLUMN PER PLAN".

Why it matters: An HSS (hollow structural section tube) column and a W-shape (wide flange) column require completely different connection detailing, plate geometry, and stiffeners. Detailing both profiles for the exact same column location makes the connection impossible to fabricate without clarification.

Suggested next step: Please confirm the correct column profile at grid Z.5. Detail 11/S500 indicates an HSS12x12 column, whereas Detail 12/S500 (called out from Detail 11 for the top connection) indicates a W27 column.

RFI draft: Please confirm the correct column profile at grid Z.5. Detail 11/S500 indicates an HSS12x12 column, whereas Detail 12/S500 (called out from Detail 11 for the top connection) indicates a W27 column.

Summary: Detail 1 on sheet S501 explicitly refers to 1/S512 for additional information regarding the HSS hanger connection. However, the details contradict each other on the upper embed plate connecting the hanger to the concrete beam. S501 specifies a "1/2"x12"x12" EMBED WITH (4)-1" DIAx8" HEADED STUDS", while the referenced S512 detail specifies a "12"x10"x1/2" EMBED WITH (4)-3/4"øx6" HEADED STUDS @ 4...

Why it matters: This conflict creates ambiguity regarding which embed plate and stud configuration should be fabricated and cast into the concrete beam. The difference in stud diameter (1" vs 3/4") and embedment length (8" vs 6") significantly affects the structural pullout and shear capacity of the hanger conne...

Suggested next step: Detail 1/S501 specifies a 1/2"x12"x12" embed plate with (4) 1" dia. x 8" headed studs for the upper hanger connection, but the referenced Detail 1/S512 specifies a 12"x10"x1/2" embed plate with (4) 3/4" dia. x 6" headed studs for the same condition. Please clarify which embed ...

RFI draft: Detail 1/S501 specifies a 1/2"x12"x12" embed plate with (4) 1" dia. x 8" headed studs for the upper hanger connection, but the referenced Detail 1/S512 specifies a 12"x10"x1/2" embed plate with (4) 3/4" dia. x 6" headed studs for the same conditio...

Summary: The FOURTH FLOOR LATERAL BEAM SCHEDULE completely omits Top (T) reinforcement for beams 4F46 and 4F48, listing only Bottom (B) reinforcement. The General Notes specify the project's lateral force resisting system as "ORDINARY REINFORCED CONCRETE MOMENT FRAMES" and mandate compliance with ACI 318-11. Under ACI 318-11 Section 21.2.2, beams of ordinary moment frames must have at least two continuo...

Why it matters: Without top reinforcement, these beams cannot resist the negative bending moments induced by structural continuity and lateral loads (such as wind or seismic forces) as intended in a moment frame assembly. This omission will lead to structural failure if constructed as scheduled.

Suggested next step: Please provide the required top reinforcement quantities, sizes, and locations for lateral beams 4F46 and 4F48 in the FOURTH FLOOR LATERAL BEAM SCHEDULE to comply with ordinary moment frame detailing requirements.

RFI draft: Please provide the required top reinforcement quantities, sizes, and locations for lateral beams 4F46 and 4F48 in the FOURTH FLOOR LATERAL BEAM SCHEDULE to comply with ordinary moment frame detailing requirements.