Multi-Story Residential: 430 Issues Found in Pre-Permit Review

The project

A 6-story multi-family residential building (R-2 occupancy) requiring comprehensive coordination across architectural, structural, mechanical, electrical, plumbing, fire protection, and civil disciplines. The project included dwelling units, common areas, mechanical closets, elevator shafts, and parking facilities with strict compliance requirements for life safety, fire protection, structural integrity, and building code standards.

Project type

Multi-story residential · R-2 occupancy · 6-story building

Codes referenced: 2021 International Building Code · 2021 International Fire Code · 2024 International Building Code · 2020 NFPA 70 (NEC) · NFPA 13 · NFPA 14 · NFPA 20

Critical findings (15)

1. Water Heater WH3 fuel type conflict: Equipment note says ELECTRIC but specification states GAS-FIRED

   Plumbing

   Critical

   On the same detail drawing (WH3 Piping Detail), Equipment Note 7 identifies the water heater as 'ELECTRIC WATER HEATER' while the narrative specification states 'WATER HEATERS (2) SHALL BE HIGH EFFICIENCY, GAS-FIRED, STORAGE TYPE.' The Water Heater Schedule on P901 confirms WH3 is ELECTRIC with 18 KW input at 208/3/60.

2. Steel Lintel ML1 and ML2 Sizes Conflict Between S002 Schedule and S104 Notes

   Structural

   Critical

   Sheet S002 Steel Lintel Schedule shows ML1 as W8x24 and ML2 as HSS16x8x1/2. However, Note 11 on sheet S104 defines ML1 as (2) 6x3 1/2x5/16 (LLV) and ML2 as W16x40 LINTEL. These are completely different steel member types - double angles versus wide flange for ML1, and hollow structural section versus wide flange for ML2.

3. Wood Lintel Schedule (WL1, WL2) conflicts with Roof Framing Plan notes - lumber depth differs (2x8 vs 2x10)

   Structural

   Critical

   The Wood Lintel Schedule on S002 specifies WL1 as (3) 2x8 and WL2 as (2) 2x8. However, Note 11 on the Roof Framing Plan S107 defines WL1 as (3) 2x10 and WL2 as (2) 2x10. The lumber depth differs by 2 inches (8" nominal vs 10" nominal), representing a significant difference in section modulus and load-carrying capacity.

4. Conflicting International Building Code years: 2015 vs 2021

   Code Compliance

   Critical

   Multiple versions of the International Building Code are referenced in this document. Found references to year(s) 2015 alongside 2021. The 2021 International Building Code (2021) was selected as the applicable code since it is the latest edition, but older version(s) are still referenced on some sheets.

5. Smoke Barrier Assembly W605-SB Lacks Required 1-Hour Fire-Resistance Rating

   Fire Protection · Code: 2021 International Building Code

   Critical

   The drawing shows wall assembly W605-SB explicitly labeled as "(SMOKE BARRIER)" but this assembly is based on the W405/W605 construction which is labeled "NON-RATED". The W605-SB shows only "5 1/2" WD FRMG" as its defining characteristic, with the base W405 assembly consisting of 5/8" GWB on both sides of 3 1/2" wood framing. IBC Section 709.3 requires smoke barriers to have a 1-hour fire-resistance rating.

6. First Floor Interior Exit Stair Doors Have 45-Minute Fire Rating While Upper Floor Stair Doors Have Higher Ratings

   Fire Protection · Code: 2021 International Fire Code

   Critical

   The door schedule shows inconsistent fire protection ratings for interior exit stairway doors across floors. First floor doors ST1-1 and ST2-1 have 45-minute fire rating. Second floor doors ST1-2 and ST2-2 have 3-hour fire rating. Third floor doors ST1-3 and ST2-3 have 90-minute fire rating. Per Section 1023.2, interior exit stairway enclosures connecting four stories or more shall have a fire-resistance rating of not less than 2 hours.

7. Conflicting National Electrical Code (NFPA 70) years: 2017 vs 2020

   Code Compliance

   Critical

   Multiple versions of the National Electrical Code (NFPA 70) are referenced in this document. Found references to year(s) 2017 alongside 2020. The 2020 NFPA 70: National Electrical Code (NEC) (2020) was selected as the applicable code since it is the latest edition, but older version(s) are still referenced on some sheets.

8. Masonry Lap Splice Lengths Violate ASD Minimums

   Structural · Code: 2021 International Building Code

   Critical

   The 'TENSION DEVELOPMENT AND LAP SPLICE LENGTH (FOR MASONRY ONLY)' schedule lists lap splice lengths that violate the minimum requirements for Allowable Stress Design (ASD). IBC Section 2107.2.1 explicitly states that for ASD, 'The length of the lapped splice shall be not less than 40 bar diameters.' For #3 bars (0.375" diameter), the minimum is 15 inches (40 * 0.375), but the schedule lists 12 inches.

9. Unsecured Masonry Soaps at Steel Lintel

   Structural · Code: 2021 International Building Code

   Critical

   The details show "CMU SOAP" installed directly against the web of a steel "WF LINTEL" without detailing any mechanical anchorage or lath system. Relying solely on mortar adhesion to smooth structural steel is not a code-compliant method for supporting masonry (veneer or otherwise).

10. Missing Uplift Anchorage for Shear Wall Hold-Down Transfer Plate

    Structural · Code: 2021 International Building Code

    Critical

    Section 2 details a wood shear wall hold-down system connected to a "CONT. 3/8" BENT P" via a welded threaded stud. However, the detail fails to specify any vertical anchorage (such as embedded anchor bolts) connecting this bent plate to the supporting "8" CMU" bond beam to resist the concentrated uplift forces generated by the hold-down.

11. Contradictory Elevator Shaft Construction and Erroneous Reinforcement Detail

    Structural · Code: 2021 International Building Code

    Critical

    The drawing contains conflicting information regarding the structural construction of the elevator shaft. Note 15 explicitly mandates a "MASONRY SHAFT" that is "GROUTED SOLID & REINFORCED". However, the framing plan (Reference 2) depicts the elevator shaft walls with thin lines consistent with the surrounding wood framing and references wood framing tags (e.g., "WL1") and wood framing details.

12. Incompatible Anchor Specification for Masonry Ledger

    Structural · Code: 2021 International Building Code

    Critical

    The drawing details (Sections 6, 7, and 8) specify "3/4"φ EXP. ANCHORS @ 24" o/c STAGGERED" connecting a 2x wood ledger to an 8" CMU wall. The wall reinforcement note ("w/ REINF. PER PLAN NOTES") implies standard reinforced masonry, which is typically partially grouted (grout only at reinforced cells). 3/4-inch diameter expansion anchors generally require a solid substrate (solid grout or concrete) to function and are not listed for use in the hollow face shells of CMU.

13. Contradictory Pile Spacing Dimensions

    Structural · Code: 2021 International Building Code

    Critical

    The drawing contains a critical contradiction regarding pile spacing dimensions. General Note 4 states "CENTER TO CENTER PILE SPACING SHALL BE 4'-6"." However, the specific dimensions on Details PC5, PC7, PC8, and PC10 explicitly show pile spacings of 3'-3" and 3'-11", which directly contradict the general note.

14. Incorrect Material Specification for Bent Plate Connection

    Structural · Code: 2021 International Building Code

    Critical

    The drawings specify a "14 GA. BENT PL" connected with "(2) 3/4"Ø EPOXY BOLTS" to anchor the wood framing to the CMU wall. 14 gauge steel (approx. 0.075" thick) is disproportionately thin for use with large 3/4" diameter structural anchors. The bearing area provided by 14 gauge steel is insufficient to develop the capacity of a 3/4" bolt.

15. Missing Return Air Path for HVAC Unit in Mechanical Closet

    Mechanical · Code: 2021 International Building Code

    Critical

    The mechanical plans (Details 1, 2, 3/M701) depict the VRP HVAC unit located inside an enclosed Mechanical Closet. Detail 4/M701 shows the ERV supplying fresh air directly into this closet ('SA DUCT DUMP IN MECHANICAL CLOSET'). However, there are no return air transfer grilles, undercut specifications, or return air ductwork shown connecting the habitable dwelling unit space to the Mechanical Closet.

Sample high priority findings (5 total)

1. Unprotected Ventilation Penetrations in 2-Hour Rated Shaft

   Fire Protection · Code: 2021 International Building Code

   High

   The detail shows a '4" DUCT METAL CONDUIT' and an intake opening penetrating the enclosure of a '2 HR. RATED SHAFT'. While the refrigerant piping note specifies a 'UL TESTED JOINT SYSTEM', there is no corresponding firestopping specification or damper shown for the 4" ventilation conduit penetrations.

2. Incompatible Roofing Materials Specified (EPDM and Asphalt)

   Architectural · Code: 2021 International Building Code

   High

   The drawing specifies 'EPDM FLASHING MEMBRANE' in direct contact with 'RUBBERIZED ASPHALT SEALANT'. Rubberized asphalt and other petroleum-based products are chemically incompatible with EPDM membranes, causing the membrane to swell, degrade, and fail, leading to leaks.

3. Prohibited Mechanical Piping Penetration in Elevator Hoistway

   Fire Protection · Code: 2021 International Building Code

   High

   The Roof Plan (Sheet M105) shows a "PIPING ROOF CURB" located directly within the enclosure labeled "ELEVATOR HOISTWAY". The leader line points to a penetration symbol inside the hoistway footprint. IBC Section 713.8.1 prohibits penetrations in shaft enclosures other than those necessary for the purpose of the shaft.

4. Toilet Rooms Improperly Connected to Return Air System

   Mechanical

   High

   In Plan 1, the Return Air system (green ductwork) serving 'CCU 06A' and 'MAINT. OFFICE 221' is incorrectly connected to grilles in 'TOILET 228' and 'TOILET 229'. The grilles in the toilets are labeled 'R2' (Return) and share the same ductwork as the office.

5. Contradiction in System Type: Branch Boxes vs. Split Systems

   Mechanical

   High

   The Drawing indicates a VRF (Variable Refrigerant Flow) system design by calling for "BRANCH BOXES ON UNISTRUT" in the refrigerant shaft area. Branch boxes (selector boxes) are specific components of Heat Recovery VRF systems. However, the Specification's Sequence of Operation explicitly describes "Ducted Split System[s]" and "Wall Mounted Split System[s]" each paired with an "Associated Heat Pump".

Issue categories

Fire Protection

Fire sprinkler systems, fire alarm systems, standpipe systems, smoke barriers, fire-resistance ratings, and fire code compliance

Structural

Steel lintels, wood framing, masonry construction, seismic connections, load paths, foundation design, and structural code compliance

Architectural

Door schedules, stair enclosures, fire ratings, wall assemblies, roof ventilation, fireblocking, and building code compliance

Mechanical

HVAC systems, ventilation strategies, ERV systems, return air paths, equipment conflicts, and mechanical code compliance

Plumbing

Water heaters, fuel types, roof drains, piping systems, and plumbing code compliance

Electrical

Electrical code references, NEC compliance, and electrical system coordination

Code Compliance

IBC compliance, IFC compliance, code edition conflicts, and building code violations

Document Coordination

Drawing conflicts, schedule mismatches, specification contradictions, and document coordination issues

Value delivered

• 430 issues surfaced before permit submission
• 15 critical permit-blocking issues identified
• Code edition conflicts caught (2015 vs 2021 IBC, 2017 vs 2020 NEC)
• Critical structural conflicts identified (steel lintel mismatches, insufficient lap splices)
• Fire protection violations caught (non-rated smoke barriers, insufficient door ratings)
• Mechanical system conflicts resolved (VRF vs split system, missing return air paths)