Plan Review: 43 Issues Found

Summary: The 'SLAB SCHEDULE - TOP BARS' specifies standard 90° hooks for multiple #4 top reinforcement bars (e.g., T101, T106, T107, T110, T111). Per ACI 318-19 Table 25.3.1, a standard 90° hook for a #4 bar requires a 12db (6-inch) straight extension and a 6db (3-inch) minimum inside bend diameter. This geometry results in a total out-to-out hook depth of at least 8.0 inches (6.0" extension + 1.5" bend...

Why it matters: Detailing a hook that is larger than the slab thickness is a severe constructability issue. If field crews attempt to place these bars as detailed, the hooks will protrude through the bottom of the slab formwork, violating bottom cover requirements and preventing proper concrete consolidation. Th...

Suggested next step: The 'SLAB SCHEDULE - TOP BARS' specifies 90° hooks for #4 bars (e.g., T101, T110). Per ACI 318 Table 25.3.1, a standard 90° hook for a #4 bar requires an 8-inch out-to-out depth (12db extension + 3db inside radius + 1db). This exceeds the physical thickness of the 5.5" (S5.5) ...

RFI draft: The 'SLAB SCHEDULE - TOP BARS' specifies 90° hooks for #4 bars (e.g., T101, T110). Per ACI 318 Table 25.3.1, a standard 90° hook for a #4 bar requires an 8-inch out-to-out depth (12db extension + 3db inside radius + 1db). This exceeds the physical...

Summary: Detail 1 ('SECTION AT NEW VENT') shows an '8" CONCRETE WALL W/ #5 @12" E.W.' supporting 'STRUCTURAL STEEL MECHANICAL EQUIP. SUPPORT'. The wall is anchored via a 'DOWEL INTO EXISTING SLAB', which is dimensioned as '5"' thick. ACI 318-19 Section 11.7.1.2 requires wall reinforcement development to comply with Section 25.4. Section 25.4.1.1 mandates that calculated tension or compression in reinfor...

Why it matters: Without adequate development length into the supporting structure, the base connection of the cantilevered wall acts as a hinge rather than a moment-resisting connection. Under lateral loads (wind, seismic) or eccentric equipment loads, this connection is highly susceptible to concrete breakout o...

Suggested next step: Please clarify how the #5 vertical wall reinforcement (or equivalent dowels) will be adequately developed into the existing 5" slab to resist overturning moments. Consider providing a new thickened concrete grade beam/curb, or designing a separate steel support frame that atta...

RFI draft: Please clarify how the #5 vertical wall reinforcement (or equivalent dowels) will be adequately developed into the existing 5" slab to resist overturning moments. Consider providing a new thickened concrete grade beam/curb, or designing a separate...

Summary: The drawing specifies an overall anchor rod length of "4'- 0"" (48 inches) with an embedment depth of "42" MIN" measured from the top of the footing down to the top of the embedded plate washer. Below this 42" line, the rod must pass through the 1 1/2" thick embed plate washer and a bottom heavy hex nut, consuming at least 3 inches of rod length. This leaves a maximum of 3 inches of rod project...

Why it matters: If fabricated as drawn, the anchor rods will be buried or protrude too little to install the base plate and nuts. Because high-strength F1554 Grade 105 rods typically cannot be welded or easily extended, this detailing error will completely halt steel erection and require costly concrete demoliti...

Suggested next step: The specified anchor rod length of 4'-0" is too short to accommodate the 42" minimum embedment, the bottom anchor plate assembly, the grout pad, the 2.5" base plate, and the top washers/nuts. This leaves a maximum of 3" of projection for a stack-up that requires well over 5". ...

RFI draft: The specified anchor rod length of 4'-0" is too short to accommodate the 42" minimum embedment, the bottom anchor plate assembly, the grout pad, the 2.5" base plate, and the top washers/nuts. This leaves a maximum of 3" of projection for a stack-u...

Summary: ACI 318-19 Section 25.4.1.2 explicitly states that "Hooks and heads shall not be used to develop bars in compression." Detail 16 mandates a "STANDARD HOOK AT BOTTOM OF ALL BARS" for the scheduled column vertical reinforcement in the foundation. Because the column footing schedule specifies footings as shallow as 1'-6" (e.g., F3.0 - 3), and Detail 16 shows a "3" COVER" at the bottom, the remaini...

Why it matters: Standard hooks provide no anchorage capacity in compression. When column bars lack adequate straight embedment length into the footing, they cannot safely transfer their full compressive design loads to the foundation, creating a severe risk of the bars punching through the bottom of the footing ...

Suggested next step: Please revise the typical column foundation details and footing depths to ensure that all vertical column reinforcement has sufficient straight embedment length to satisfy compression development requirements without relying on hooks, per ACI 318-19 Section 25.4.1.2.

RFI draft: Please revise the typical column foundation details and footing depths to ensure that all vertical column reinforcement has sufficient straight embedment length to satisfy compression development requirements without relying on hooks, per ACI 318-...

Summary: General Note 1 specifies a 1 1/2" clear cover for top reinforcement. Keynote S5.5 specifies #4 top bars in both directions (occupying 1.0" of vertical depth total), meaning the top two layers of reinforcement occupy the slab depth from 1.5" down to 2.5". However, the Tendon Profile Legend specifies the PT tendon high point at exactly 1 3/4" (1.75") below the top of the slab. This places the pos...

Why it matters: This physical collision makes the slab unbuildable as detailed. Resolving the conflict requires either lowering the tendon high point or reducing the rebar cover. Lowering the PT tendon reduces its effective depth, which diminishes the slab's structural moment capacity and could violate the stren...

Suggested next step: The specified 1 1/2" cover for #4 top bars places the outermost reinforcement from 1.5" to 2.0" below the slab surface. This physically clashes with the PT Tendon Profile Legend, which sets the tendon high point at 1 3/4" below the top. Please clarify the intended depths. If t...

RFI draft: The specified 1 1/2" cover for #4 top bars places the outermost reinforcement from 1.5" to 2.0" below the slab surface. This physically clashes with the PT Tendon Profile Legend, which sets the tendon high point at 1 3/4" below the top. Please cla...

Summary: General Note 1 specifies a 1½" clear cover for top reinforcement, which consists of #4 bars (0.5" diameter). This places the centroid of the top reinforcement exactly 1.75" below the top of the slab. The Tendon Profile Legend specifies the PT tendon high points are also located 1¾" (1.75") below the top of the slab. Because both the PT tendon high points and the top reinforcement are placed ove...

Why it matters: This geometric impossibility means the construction documents fail to accurately establish the relative locations of structural members and reinforcement as required by IBC 1603.1 and 1901.5(3). During construction, either the tendon or the reinforcement must be lowered to avoid the physical clas...

Suggested next step: Please clarify the intended elevations for PT tendons and top reinforcement at column supports. Should the tendon high point be lowered or top cover increased? Please verify that structural capacity is maintained with the revised effective depth.

RFI draft: Please clarify the intended elevations for PT tendons and top reinforcement at column supports. Should the tendon high point be lowered or top cover increased? Please verify that structural capacity is maintained with the revised effective depth.

Summary: General Note 1 specifies '1½" COVER FOR TOP REINFORCEMENT BARS'. Keynote S5.5 indicates the top slab bars are #4 (0.5" diameter). This places the centroid of the top reinforcement at 1.75" below the top of the slab (1.5" cover + 0.25" half-diameter). However, the Tendon Profile Legend specifies 'HIGH POINT = 1¾" BELOW TOP OF SLAB', which places the post-tensioning tendon centroid exactly at 1.7...

Why it matters: IBC Section 1603.1 and 1901.5(3) require construction documents to accurately show the size and relative locations of structural members and reinforcement. Specifying physically intersecting elevations for the tendons and top reinforcement fails this requirement and renders the design unbuildable...

Suggested next step: The specified 1 3/4" PT tendon high point directly clashes with the 1 1/2" clear cover for the #4 top reinforcement. Please review the tendon profiles and top cover requirements, and provide revised dimensions to ensure adequate physical clearance while maintaining the require...

RFI draft: The specified 1 3/4" PT tendon high point directly clashes with the 1 1/2" clear cover for the #4 top reinforcement. Please review the tendon profiles and top cover requirements, and provide revised dimensions to ensure adequate physical clearance...

Summary: The drawing (Detail 15, SECTION) directs the contractor to engage the geotechnical engineer to observe the sides of the rock anchor holes for solid rock. This directly violates IBC Section 1704.2, which strictly mandates that the owner, or the owner's authorized agent (other than the contractor), must employ the approved agencies to provide special inspections and tests.

Why it matters: Allowing the contractor to hire the inspecting engineer creates a conflict of interest and violates the administrative requirements of the building code for independent oversight. The building official will likely reject the statement of special inspections and withhold permits or the Certificate...

Suggested next step: Revise the note in the TYPICAL ROCK ANCHOR DETAIL to state that the Owner or the Owner's authorized agent shall engage the Geotechnical Engineer to perform the required observations, in compliance with IBC Section 1704.2.

RFI draft: Revise the note in the TYPICAL ROCK ANCHOR DETAIL to state that the Owner or the Owner's authorized agent shall engage the Geotechnical Engineer to perform the required observations, in compliance with IBC Section 1704.2.

Summary: Detail 3 ('AT ROOF') shows kickers framing into roof joists via an L4x4 angle, with an additional L2x2 bracing to the bottom chord. The drawing explicitly directs to the 'KICKER SCHEDULE' for sizing. However, the schedule only provides the kicker length and size, failing to specify the concentrated loads and connection forces imparted on the joists.

Why it matters: IBC Section 2207.2 explicitly requires construction documents to indicate special loads on joists, including concentrated loads and connection forces. Without this force data, the joist manufacturer cannot properly design the joist elements (especially the out-of-plane lateral strength of the cho...

Suggested next step: Please provide the concentrated loads and connection forces for all kickers framing into steel joists in the Kicker Schedule or structural notes, as required by IBC 2207.2, so the joist manufacturer can incorporate them into their design.

RFI draft: Please provide the concentrated loads and connection forces for all kickers framing into steel joists in the Kicker Schedule or structural notes, as required by IBC 2207.2, so the joist manufacturer can incorporate them into their design.

Summary: The drawing specifies a minimum bearing pressure of '300 KSF' (300,000 psf) for several column and wall footing schedules. According to IBC Section 1806.2, presumptive load-bearing values shall not exceed the limits specified in Table 1806.2, which caps the maximum vertical foundation pressure at 12,000 psf (12 KSF) for the hardest rock (crystalline bedrock). A bearing pressure of 300 KSF vastl...

Why it matters: This is likely a typographical error intended to read 3,000 PSF (3 KSF). However, as explicitly noted on the drawing, this specification requires the contractor to achieve an impossible bearing capacity. If left uncorrected, the geotechnical engineer cannot certify the foundation subgrade, result...

Suggested next step: The column and wall footing schedules specify a 'MIN BRG PRESSURE 300 KSF', which exceeds code allowable limits and standard soil capacity. Please confirm if this is a typographical error intended to be 3,000 PSF (3 KSF) and revise the footing schedules to indicate a correct, ...

RFI draft: The column and wall footing schedules specify a 'MIN BRG PRESSURE 300 KSF', which exceeds code allowable limits and standard soil capacity. Please confirm if this is a typographical error intended to be 3,000 PSF (3 KSF) and revise the footing sch...

Summary: Detail 15 specifies top plate anchors as Headed Concrete Anchors (HCA), which are cast-in-place. However, the graphic depicts a post-installed through-bolt connection to a bottom backing plate.

Why it matters: The contradiction between cast-in anchors (HCA) and a through-bolted backing plate creates ambiguity in procurement and installation responsibilities. This violates the code requirement that contract documents be consistent with design assumptions, leading to potential construction errors and del...

Suggested next step: Clarify whether the post baseplate requires a cast-in embed plate with Headed Concrete Anchors (HCAs) or a field-installed through-bolted connection with a bottom backing plate.

RFI draft: Clarify whether the post baseplate requires a cast-in embed plate with Headed Concrete Anchors (HCAs) or a field-installed through-bolted connection with a bottom backing plate.

Summary: The structural general notes state a uniform clear concrete cover of 1-1/2" for the formed edges of all beams and columns. However, the concrete material schedule indicates the project includes exterior columns ('Ext. Columns'). Per ACI 318-19 Table 20.5.1.3.1, concrete members 'exposed to weather or in contact with ground' require a minimum cover of 2" when utilizing No. 6 through No. 18 prima...

Why it matters: Providing insufficient concrete cover on exterior structural members exposes the primary reinforcing steel to environmental moisture and chlorides. This significantly increases the risk of premature corrosion, which can lead to concrete spalling and compromise the load-bearing capacity and servic...

Suggested next step: Please clarify the clear concrete cover requirements for exterior beams and columns. Recommend updating the general notes to specify a minimum 2" clear cover for members exposed to weather utilizing No. 6 through No. 18 bars, in accordance with ACI 318-19 Table 20.5.1.3.1.

RFI draft: Please clarify the clear concrete cover requirements for exterior beams and columns. Recommend updating the general notes to specify a minimum 2" clear cover for members exposed to weather utilizing No. 6 through No. 18 bars, in accordance with AC...

Summary: The structural general notes specify 1-1/2" of clear cover for the bottom steel of all slabs-on-grade. The concrete schedule indicates the project includes exterior slabs-on-grade ('Ext. Slab'), which are typically cast directly against the earth. According to ACI 318-19 Table 20.5.1.3.1, any concrete member 'cast against and permanently in contact with ground' requires a minimum of 3" of concr...

Why it matters: If exterior slabs-on-grade are cast directly against the soil with only 1-1/2" of bottom cover, the reinforcement will be highly susceptible to rapid corrosion from soil moisture. This causes premature deterioration, cracking, and spalling of the slab.

Suggested next step: Please clarify the clear cover requirements for slabs-on-grade that are cast directly against the soil (such as exterior slabs). Update the general notes to require a minimum of 3" clear cover for concrete cast against and permanently in contact with the ground, per ACI 318-19...

RFI draft: Please clarify the clear cover requirements for slabs-on-grade that are cast directly against the soil (such as exterior slabs). Update the general notes to require a minimum of 3" clear cover for concrete cast against and permanently in contact w...

Summary: The drawing specifies "#4 @ 24" O.C. TYP." for the perimeter hatched area. Based on the thinnest slab specified in the keynotes (5.5 inches), the gross concrete area (Ag) is 66 sq in/ft. ACI 318-19 Section 8.6.1.1 requires a minimum flexural reinforcement area (As,min) of 0.0018Ag, which equals 0.1188 sq in/ft. The provided #4 bars at 24 inches on center only supply 0.10 sq in/ft, which is belo...

Why it matters: Providing less than the minimum required flexural reinforcement can lead to excessive cracking, loss of structural continuity, and potential localized failure under design loads. This creates a weak link at the edge pour strip/slab perimeter. This will be flagged during structural permit review a...

Suggested next step: Please revise the reinforcement spacing in the perimeter hatched area to meet the minimum flexural reinforcement requirements of ACI 318-19 Section 8.6.1.1 (e.g., decrease spacing to 18 inches or 12 inches on center to match the adjacent slab).

RFI draft: Please revise the reinforcement spacing in the perimeter hatched area to meet the minimum flexural reinforcement requirements of ACI 318-19 Section 8.6.1.1 (e.g., decrease spacing to 18 inches or 12 inches on center to match the adjacent slab).

Summary: Detail 2 (TYPICAL TRENCH SECTION) specifies a bottom slab overall thickness of exactly 6 inches and shows it reinforced with "(3) #5 BOTTOM" bars. However, ACI 318-19 Section 13.3.1.2 requires that the overall depth of a foundation be selected such that the effective depth of the bottom reinforcement is at least 6 inches. Because the overall depth of the trench bottom is only 6 inches, the effe...

Why it matters: An inadequate effective depth reduces the flexural and shear capacity of the trench foundation. Since the trench transmits vertical loads (such as its own weight, the grating, and potential traffic) to the ground, insufficient structural depth could lead to cracking, settlement, or failure of the...

Suggested next step: Please increase the overall thickness of the trench bottom slab to ensure that the effective depth of the bottom reinforcement is at least 6 inches, in compliance with ACI 318-19 Section 13.3.1.2.

RFI draft: Please increase the overall thickness of the trench bottom slab to ensure that the effective depth of the bottom reinforcement is at least 6 inches, in compliance with ACI 318-19 Section 13.3.1.2.