Plan Review: 171 Issues Found

Summary: The Reinforcing Material Table on S-012 allows Fibermesh to be substituted for Welded Wire Reinforcing (WWR) in stairs. However, ACI 318-14 Chapter 20 applies strictly to steel reinforcement, requiring nonprestressed reinforcement to be deformed steel bars or wires. Synthetic fibers (Fibermesh) are not a permitted material substitute for structural steel reinforcement.

Why it matters: Using Fibermesh in place of structural steel reinforcement (WWR) results in an unreinforced concrete structural member. This poses a critical life safety and code compliance risk, as the concrete stairs will lack the necessary tensile reinforcement to safely support occupancy loads.

Suggested next step: Please revise the Reinforcing Material Table to remove the note allowing Fibermesh substitution for WWR in stairs. Confirm that all concrete stairs will be provided with fully compliant deformed steel reinforcement per ACI 318-14.

RFI draft: Please revise the Reinforcing Material Table to remove the note allowing Fibermesh substitution for WWR in stairs. Confirm that all concrete stairs will be provided with fully compliant deformed steel reinforcement per ACI 318-14.

Summary: The "TYPICAL ELEVATED SLAB STEP DETAIL" specifies a "LAP SPLICE" for the main flexural reinforcement at the step with a length of "6D (12\" MIN)". The detail shows the reinforcement bending 90 degrees to form this overlap. If "6D" refers to 6 bar diameters ($6d_b$), this directly violates ACI 318 Table 25.3.1, which mandates a minimum straight extension of $12d_b$ for standard 90-degree hooks u...

Why it matters: Specifying an inadequate lap splice or hook extension will prevent the main slab reinforcement from fully developing its yield strength at the step transition. This creates a severe structural weakness at a critical flexural location, drastically reducing the moment transfer capacity and potentia...

Suggested next step: Please revise Detail C (Typical Elevated Slab Step Detail) to specify a tension lap splice length calculated in accordance with ACI 318 Section 25.5 based on the full development length of the reinforcement. If the bent bars are acting as standard hooks for tension development...

RFI draft: Please revise Detail C (Typical Elevated Slab Step Detail) to specify a tension lap splice length calculated in accordance with ACI 318 Section 25.5 based on the full development length of the reinforcement. If the bent bars are acting as standard...

Summary: Detail D specifies stacking "(2) - PT 2x4" to form a sill plate base for a wood stair stringer, and anchoring these plates to the concrete haunch with "3 1/4" LONG TAPCON SCREWS". According to IBC Section 2304.2, structural calculations must use net actual sizes, which is 1.5 inches for a nominal 2-inch member. Two stacked 2x4s equal 3.0 inches in total thickness. Fastening a 3.25-inch long scr...

Why it matters: A 1/4-inch embedment depth into concrete for a 1/4-inch diameter screw anchor is completely insufficient to transfer shear or uplift loads from the stair stringer into the foundation. This creates a severe life-safety risk where the primary egress stair could detach from its base. During construc...

Suggested next step: Please revise Detail D to specify a longer Tapcon screw that provides adequate structural embedment into the concrete (e.g., minimum 1-1/2" to 2" embedment, requiring a 4-1/2" or 5" long screw) for anchoring the double 2x4 sill plates.

RFI draft: Please revise Detail D to specify a longer Tapcon screw that provides adequate structural embedment into the concrete (e.g., minimum 1-1/2" to 2" embedment, requiring a 4-1/2" or 5" long screw) for anchoring the double 2x4 sill plates.

Summary: Detail 1 specifies a connection utilizing `(2)L6x6x3/8 x 6" LONG STEEL ANGLES WITH 3/4" DIAMETER THRU-BOLT` located in `2 1/2" VERTICAL SLOTS`. The detail explicitly directs to `LOCATE BOLT AT BOTTOM OF SLOTS` and graphically provides a `1 1/2"` vertical dimension locating the bolt centerline below the embed plate. A 2.5" vertical slot with the bolt positioned at the bottom extends 2.125" upwar...

Why it matters: This geometry is physically impossible to construct. Extending the slotted hole past the top edge completely severs the structural angle, leaving no continuous material to weld to the embed plate. This detailing flaw provides zero structural capacity for the connection and directly violates the s...

Suggested next step: Please revise the 1 1/2" vertical dimension. To accommodate a 2 1/2" vertical slot with the bolt located at the bottom while maintaining the required minimum edge distance from the top of the slot to the top edge of the angle per AISC 360, the bolt centerline must be located s...

RFI draft: Please revise the 1 1/2" vertical dimension. To accommodate a 2 1/2" vertical slot with the bolt located at the bottom while maintaining the required minimum edge distance from the top of the slot to the top edge of the angle per AISC 360, the bol...

Summary: Details 5 and 6 show corridor framing and a "CORRIDOR BEAM" hung from a continuous ledger that is fastened to vertical blocking, which is nailed directly to the "TRUSS END VERTICAL". IBC Section 2303.4.5 requires that additions of loads to any truss member shall not be permitted without verification that the truss is capable of supporting the additional loading. The provided details fail to pro...

Why it matters: Standard roof trusses are designed solely for roof loads. Hanging a corridor structure and beams from the end vertical introduces substantial unintended point and continuous loads. Without explicit load values and instructions provided to the truss designer, the trusses will be under-designed, po...

Suggested next step: Please specify the exact loads for the corridor beam and framing applied to the truss end verticals, and add a note requiring the truss manufacturer to verify and design the trusses to support these additional loads.

RFI draft: Please specify the exact loads for the corridor beam and framing applied to the truss end verticals, and add a note requiring the truss manufacturer to verify and design the trusses to support these additional loads.

Summary: The drawing contains a critical structural sizing error where headers for lower floor load-bearing walls are undersized compared to the upper floors. Specifically, the 'DROPPED HEADERS AND POSTS' schedule requires a (3)2x10 header for Fifth Floor exterior wall openings (≥ 6'-0" & < 8'-6"), but specifies a significantly smaller (3)2x6 header for the Fourth and Third Floors for the exact same ope...

Why it matters: If constructed as scheduled, the (3)2x6 headers on the Third and Fourth floors will be severely overloaded by the accumulated building weight from the upper floors and roof. This will lead to excessive deflection, framing damage, and potential catastrophic failure of the bearing wall headers.

Suggested next step: Please review and revise the DROPPED HEADERS AND POSTS schedule to ensure headers on lower floors (Fourth and Third floors) are adequately sized to carry the accumulated gravity loads from the upper floors and roof. The currently scheduled (3)2x6 headers appear structurally in...

RFI draft: Please review and revise the DROPPED HEADERS AND POSTS schedule to ensure headers on lower floors (Fourth and Third floors) are adequately sized to carry the accumulated gravity loads from the upper floors and roof. The currently scheduled (3)2x6 ...

Summary: Drawing Note 2 under 'WOOD ROOF FRAMING PLAN NOTES' explicitly states that hold-down anchors for roof joists and trusses 'shall be sized and specified by the joist or truss supplier'. However, IBC Section 2303.4.4 mandates that the design for the transfer of loads and anchorage of each truss to the supporting structure is the responsibility of the registered design professional.

Why it matters: A truss supplier is a delegated designer responsible only for the truss itself, not the global main wind and seismic force-resisting system. Delegating the sizing of the anchorage (the connection to the supporting walls) to the truss supplier without providing the required uplift and shear capaci...

Suggested next step: Please revise Note 2 and the construction documents to specify the required hold-down anchors, sizes, and capacities for all roof joists and trusses, as IBC 2303.4.4 requires the registered design professional to design the anchorage to the supporting structure.

RFI draft: Please revise Note 2 and the construction documents to specify the required hold-down anchors, sizes, and capacities for all roof joists and trusses, as IBC 2303.4.4 requires the registered design professional to design the anchorage to the suppor...

Summary: Detail B specifies an 18-inch LVL acting as a load-bearing beam framed tight between roof trusses to support a condenser wall. The detail directs connecting this flush-framed member using a "SIMPSON H3 HURRICANE TIE EACH SIDE TOP AND BOTTOM". A hurricane tie is an uplift strap, not a joist hanger designed to support downward gravity shear loads. Section 2303.5 requires joist hangers to be in ac...

Why it matters: H3 ties lack the required structural bearing seat and downward shear capacity to support heavy flush-framed beams. Under the dead loads of the LVL and condenser wall, plus live and equipment loads, the hurricane ties will likely buckle or shear. This deficient connection poses a severe risk of lo...

Suggested next step: Please provide a revised connection detail specifying an approved face-mount joist hanger sized to support the gravity, shear, and uplift loads of the 18-inch LVL beam, ensuring compliance with ASTM D7147.

RFI draft: Please provide a revised connection detail specifying an approved face-mount joist hanger sized to support the gravity, shear, and uplift loads of the 18-inch LVL beam, ensuring compliance with ASTM D7147.

Summary: Details 1, 3, and 5 depict interior shear walls where the bottom plate bears directly on top of the 'GYP-CRETE' layer rather than bearing on the structural 'FLOOR SHEATHING' or framing below. Placing shear walls over a non-structural gypsum concrete topping compromises the transfer of lateral loads from the wall to the floor diaphragm. The 'SHEAR WALL BOTTOM PLATE FASTENERS' are shown spanning ...

Why it matters: If constructed as drawn, the gypsum concrete will crush under overturning and lateral loads, and the boundary fasteners will deflect excessively. This invalidates the tabulated fastener slip and wall anchorage elongation assumptions required for calculating shear wall deflection (IBC 2305.3), sig...

Suggested next step: Revise interior shear wall details (1, 3, and 5) to require the shear wall bottom plates to bear and attach directly on the structural floor sheathing. Clarify that the gyp-crete is to be poured around the plates after framing, or specify solid treated wood blocking of equal t...

RFI draft: Revise interior shear wall details (1, 3, and 5) to require the shear wall bottom plates to bear and attach directly on the structural floor sheathing. Clarify that the gyp-crete is to be poured around the plates after framing, or specify solid tr...

Summary: The 'DROPPED HEADERS AND POSTS' schedule is inverted relative to gravity load paths. As specified in Note 2, the walls indicated are below the framing level. At the Roof level (supporting only roof loads), exterior wall openings up to 8'-6" are sized with (3)2x10 MSR headers and (2)2x6JS (two jack studs). Conversely, at the Third Floor level (supporting the 4th floor, 5th floor, and roof), the ...

Why it matters: Gravity loads accumulate at lower stories, meaning structural support members must increase in size or quantity. Installing smaller (3)2x6 headers and single jack studs at the heavily loaded lower floors will cause massive overstress, leading to excessive deflection, shear failure, or catastrophi...

Suggested next step: Review and revise the 'DROPPED HEADERS AND POSTS' schedule. The framing levels appear to be inverted, incorrectly assigning the largest structural members to the Roof and the smallest to the Third Floor. Provide an updated schedule that correctly sizes headers and jack studs t...

RFI draft: Review and revise the 'DROPPED HEADERS AND POSTS' schedule. The framing levels appear to be inverted, incorrectly assigning the largest structural members to the Roof and the smallest to the Third Floor. Provide an updated schedule that correctly ...

Summary: The 'DROPPED HEADERS AND POSTS' schedule indicates that header sizes at exterior bearing walls decrease at lower floors, which contradicts the physical accumulation of gravity loads. For an opening width ≥ 6'-0" & < 8'-6" in a 2x6 wall, the schedule specifies a '(3)2x10MSR' header at the Roof level (supporting only the roof). However, for the exact same opening size at the Fourth Floor level—wh...

Why it matters: Gravity loads accumulate from the top of the structure downward. Therefore, the required capacity of a bearing wall header for a given opening width must equal or exceed the capacity of an identically sized opening on the floors above it. Sizing the lower-level headers as '(3)2x6' when the top le...

Suggested next step: Please revise the 'DROPPED HEADERS AND POSTS' schedule to accurately size the Fourth and Third Floor headers at exterior bearing walls, ensuring they have sufficient capacity to safely support the cumulative gravity loads from the upper floors and roof in accordance with NDS 2...

RFI draft: Please revise the 'DROPPED HEADERS AND POSTS' schedule to accurately size the Fourth and Third Floor headers at exterior bearing walls, ensuring they have sufficient capacity to safely support the cumulative gravity loads from the upper floors and...

Summary: Across multiple framing plans (e.g., Stair B Third Floor and Stair A Roof Framing), multi-ply members are specified to bear on single jack studs. Specifically, 2-ply LVL beams "(2)12LVL" (minimum 3.0 inches wide) bear on single 2x4 jack studs "(1)2x4JS", and a 3-ply header "(3)2x10" (4.5 inches wide) bears on a single 2x6 jack stud "(1)2x6JS". Per NDS Table 1B, a single nominal 2x jack stud pro...

Why it matters: This configuration directly violates NDS 3.1.3, which requires connections to ensure each individual member carries its proportional stress. Because the outer plies of the beam lack direct bearing support, they must rely entirely on internal fasteners to transfer shear to the supported ply at the...

Suggested next step: Revise the framing details to provide adequate bearing width for all plies of the multi-ply beams and headers. Ensure the number of jack studs matches or exceeds the width of the supported beams (e.g., use at least two jack studs for a 2-ply LVL, and three jack studs for a 3-p...

RFI draft: Revise the framing details to provide adequate bearing width for all plies of the multi-ply beams and headers. Ensure the number of jack studs matches or exceeds the width of the supported beams (e.g., use at least two jack studs for a 2-ply LVL, ...

Summary: The detail calls to 'FASTEN TO TOP CHORD OF TRUSSES W/ SIMPSON SDS25800 SCREWS AT 12"oc'. An SDS25800 screw is 8 inches long. The assembly consists only of a PT sleeper, roof sheathing, and a truss top chord, with a combined thickness that is typically around 3.75" to 5.75". Driving an 8" screw into this assembly causes severe over-penetration, meaning the partially threaded portion will likely...

Why it matters: Balcony decking and sleepers require solid withdrawal capacity to resist wind uplift. Fasteners that are excessively long will not engage their threads in the structural member, and intermediate fasteners that miss the trusses entirely will fail structural minimum penetration requirements. This c...

Suggested next step: Verify the actual thickness of the PT sleeper and truss top chord, and revise the Simpson SDS screw length to ensure threads are fully engaged within the truss chord without protruding. Also, clarify the sleeper orientation; if sleepers are perpendicular to trusses, revise the...

RFI draft: Verify the actual thickness of the PT sleeper and truss top chord, and revise the Simpson SDS screw length to ensure threads are fully engaged within the truss chord without protruding. Also, clarify the sleeper orientation; if sleepers are perpen...

Summary: Sheet S-310 provides typical elevator wall details and specifies the elevator shaft as a concrete wall (e.g., 'TYPICAL CONCRETE DETAILS', 'CONCRETE WALL BEYOND'). In direct contradiction, Sheet S-654 provides floor/wall details at the elevator shaft and specifies it as a masonry wall (e.g., 'MASONRY ELEVATOR SHAFT', 'CMU WALL BEYOND').

Why it matters: Inconsistent shaft wall materials will cause major coordination issues between structural framing, architectural plans, and elevator manufacturer requirements (e.g., cast-in-place concrete rail embeds versus masonry anchors). This impacts bidding, structural capacity, and fire-rating continuity.

Suggested next step: Please clarify the required material for the elevator shaft walls. Are they intended to be cast-in-place concrete as detailed on S-310, or CMU as detailed on S-654? Update the typical details and plans to consistently reflect the correct material.

RFI draft: Please clarify the required material for the elevator shaft walls. Are they intended to be cast-in-place concrete as detailed on S-310, or CMU as detailed on S-654? Update the typical details and plans to consistently reflect the correct material.

Summary: The Foundation Plan Notes on the drawing state that backfill against foundation walls shall not exceed 7'-0" unbalanced height until the slab above is placed and cured. However, the Specification strictly prohibits placing backfill on basement walls without adequate bracing or until the slab is placed, and requires maintaining equal heights of backfill on both sides of foundation walls at the s...

Why it matters: Permitting up to 7'-0" of unbalanced backfill on an unbraced, freestanding foundation wall prior to slab placement creates a severe risk of structural failure, wall blow-out, or overturning during construction. The specification safely mandates equal backfill heights or adequate bracing, which th...

Suggested next step: Please clarify the allowable unbalanced backfill height for foundation and basement walls prior to slab placement. Should the contractor follow Drawing Note 9 allowing 7'-0" unbalanced, or the Specification FDN Notes 11 and 12 requiring equal heights and prohibiting unbraced b...

RFI draft: Please clarify the allowable unbalanced backfill height for foundation and basement walls prior to slab placement. Should the contractor follow Drawing Note 9 allowing 7'-0" unbalanced, or the Specification FDN Notes 11 and 12 requiring equal heig...