Plan Review: 23 Issues Found

Summary: The Foundation Wall Section on sheet A-2.3 specifies 15M dowels with a 24" vertical leg and a 12" horizontal leg at 32" on center spacing. However, the general structural note on the Footing Plan (A-3.1) specifies the poured foundation wall with 15M bent dowels at 24"x24" (equal legs) at 16" on center spacing. Both references describe the standard dowel connection between the poured concrete fo...

Why it matters: This is a critical structural discrepancy. Dowels connecting the wall to the footing are essential for transferring shear and preventing sliding at the cold joint. Using the lesser specification (12" horiz. leg at 32" o.c.) would result in roughly one-quarter the total steel embedment into the fo...

Suggested next step: Please clarify the correct dowel specification for the standard 10" poured concrete foundation wall-to-footing connection. The Foundation Wall Section on A-2.3 shows 15M dowels at 24" vert. x 12" horiz. @ 32" o.c., while the Footing Plan note on A-3.1 specifies 15M bent dowels...

RFI draft: Please clarify the correct dowel specification for the standard 10" poured concrete foundation wall-to-footing connection. The Foundation Wall Section on A-2.3 shows 15M dowels at 24" vert. x 12" horiz. @ 32" o.c., while the Footing Plan note on A...

Summary: The roof assembly note on the 2nd Floor Plan (A-3.4) specifies '2"x4" TAPER SLEEPERS' and '3/4" T&G PLYWOOD', whereas the Roof Plan (A-3.5) specifies '2"x6" TAPERED SLEEPERS' and '3/4" PLYWOOD' (without the tongue-and-groove designation). These are two different specifications for the same rear deck flat roof assembly, creating a direct dimensional conflict on the sleeper size (2x4 vs 2x6) and ...

Why it matters: The sleeper size directly affects the structural capacity of the tapered roof drainage system, the achievable slope for drainage, and material procurement. A 2x6 sleeper can achieve greater taper over a given span than a 2x4. The plywood specification (T&G vs non-T&G) impacts panel edge support, ...

Suggested next step: Please clarify the correct tapered sleeper size for the rear deck flat roof assembly — is it 2"x4" as noted on A-3.4 or 2"x6" as noted on A-3.5? Also confirm whether the plywood substrate should be tongue-and-groove (T&G) as called out on A-3.4, or standard plywood as indicate...

RFI draft: Please clarify the correct tapered sleeper size for the rear deck flat roof assembly — is it 2"x4" as noted on A-3.4 or 2"x6" as noted on A-3.5? Also confirm whether the plywood substrate should be tongue-and-groove (T&G) as called out on A-3.4, o...

Summary: On the architectural Basement Floor Plan (A-3.2), the south foundation wall between section cuts 1/A-5.5 and 1/A-5.4 is drawn straight, with a 6'-0" window well projecting outward. However, on the Structural Footing Plan (A-3.1), the foundation wall in this exact same bay features a 2'-0" deep by 9'-0" wide inward jog/recess.

Why it matters: If the foundation is poured according to the structural plan with an inward jog, it will encroach 2'-0" into the architectural layout, severely impacting the Bar and adjacent bathroom space. Alternatively, if poured straight, it won't match the structural layout and footing design.

Suggested next step: Please clarify the correct foundation wall geometry at the south window well. Should the foundation wall be straight as shown on A-3.2, or feature a 2'-0" inward jog as shown on A-3.1?

RFI draft: Please clarify the correct foundation wall geometry at the south window well. Should the foundation wall be straight as shown on A-3.2, or feature a 2'-0" inward jog as shown on A-3.1?

Summary: The Foundation Wall Section detail shows the basement slab assembly with '2" (50mm) RIGID INSULATION' below the slab. However, the specification schedule S1 requires '4" (100mm) RIGID INSULATION' for the basement slab assembly. The drawing provides only half the specified insulation thickness.

Why it matters: This discrepancy reduces the sub-slab insulation by 50%, which will negatively impact the thermal performance of the basement floor and may fail to meet energy code requirements. Constructing with 2" insulation instead of 4" would require costly remediation after the slab is poured.

Suggested next step: Request clarification on the correct rigid insulation thickness below the basement slab. The specification schedule S1 calls for 4" (100mm) rigid insulation, while the Foundation Wall Section detail on A-2.3 shows 2" (50mm). Please confirm which value governs and issue a revis...

RFI draft: Request clarification on the correct rigid insulation thickness below the basement slab. The specification schedule S1 calls for 4" (100mm) rigid insulation, while the Foundation Wall Section detail on A-2.3 shows 2" (50mm). Please confirm which v...

Summary: The drawing specifies the 12" poured concrete retaining wall at the Basement Terrace with 1-1/2" rebar cover on both outside and inside faces. The outside face of this retaining wall is backfilled against soil, and the inside face is exposed to the open-air exterior terrace. Both conditions meet the specification's criteria for concrete "cast against soil and/or exposed to freezing," which requ...

Why it matters: Insufficient concrete cover on a retaining wall exposed to soil and freezing conditions significantly reduces durability. In Ontario's freeze-thaw climate, inadequate cover accelerates carbonation, chloride ingress, and spalling, potentially leading to premature structural deterioration of the re...

Suggested next step: Request clarification from the structural engineer on the retaining wall rebar cover. The drawing specifies 1-1/2" cover on both faces, while Concrete Note 4.3 requires 75mm (3") cover for concrete cast against soil and/or exposed to freezing. Confirm whether the retaining wal...

RFI draft: Request clarification from the structural engineer on the retaining wall rebar cover. The drawing specifies 1-1/2" cover on both faces, while Concrete Note 4.3 requires 75mm (3") cover for concrete cast against soil and/or exposed to freezing. Con...

Summary: The SOUTH ( FRONT ) ELEVATION indicates a 3" clearance above the exterior windows, such as the 132x87 window on the second floor. This window is dimensioned at 7'-3" tall, and the ceiling height is 9'-0" from the FIN. 2ND FLOOR. Given the 1'-6" space below the window, the window top reaches 8'-9", leaving a 3" gap to the ceiling. A standard double top plate requires exactly 3" of space, meaning...

Why it matters: Large windows spanning 132 inches (11 feet) require significantly deep structural lintels (such as LVLs or large built-up wood beams). The framing cannot be completed as drawn without either dropping the window head heights (which affects window procurement and the architectural facade) or utiliz...

Suggested next step: Please review the window head heights and the architectural elevations. The 3" gap to the ceiling only accommodates the double top plates, leaving no room for the structural headers required by the typical framing details. Please advise if the window heights should be reduced,...

RFI draft: Please review the window head heights and the architectural elevations. The 3" gap to the ceiling only accommodates the double top plates, leaving no room for the structural headers required by the typical framing details. Please advise if the win...

Summary: On the 1st Floor Plan (A-3.3), the load-bearing wall separating the foyer from the garage is hatched and annotated as '2x4@16"o.c.' However, the wall type schedule on A-2.1 specifies partition type P3 for the garage-to-house wall with 2x6 studs (noted as 'GARAGE SIDE'), and General Note 05 on the same sheet requires R22 insulation in walls between the house and garage. A 2x4 stud cavity (3.5") ...

Why it matters: This conflict affects fire separation integrity, energy code compliance (SB-12), and structural adequacy. The wall between the house and garage requires gasproofing, specific fire resistance, and R22 insulation per OBC. Using 2x4 studs instead of 2x6 reduces insulation capacity and may compromise...

Suggested next step: Clarify the framing size for the load-bearing wall between the foyer and the garage. Should this wall be 2x6@16" o.c. to match partition type P3 and accommodate R22 insulation as required by Note 05? If 2x4 is intended, specify how R22 insulation will be achieved in the reduce...

RFI draft: Clarify the framing size for the load-bearing wall between the foyer and the garage. Should this wall be 2x6@16" o.c. to match partition type P3 and accommodate R22 insulation as required by Note 05? If 2x4 is intended, specify how R22 insulation ...

Summary: The foundation wall assembly FW1 on sheet A-2.1 specifies 2" of closed-cell spray foam labeled as R10ci (continuous insulation) applied directly to the concrete wall, plus R12 spray foam between 2x4 wood studs. However, the SB-12 compliance table on sheet A-2.2 requires basement walls to have a minimum nominal R-value of 20ci (continuous insulation). Only the R10 spray foam applied directly to ...

Why it matters: This discrepancy means the basement wall assembly as specified does not meet the energy efficiency requirements of the Ontario Building Code Supplementary Standard SB-12 Compliance Package A1. During permit review or field inspection, this shortfall could result in a code deficiency notice. Corre...

Suggested next step: Confirm the required continuous insulation value for the basement foundation walls. The SB-12 compliance table specifies R20ci for basement walls, but the FW1 assembly only provides R10ci (2" spray foam on the concrete wall). Should the continuous insulation layer be increased...

RFI draft: Confirm the required continuous insulation value for the basement foundation walls. The SB-12 compliance table specifies R20ci for basement walls, but the FW1 assembly only provides R10ci (2" spray foam on the concrete wall). Should the continuous...

Summary: There are multiple contradictions in the stated area calculations across the Site Plan schedules and diagrams. The 'LOT COVERAGE' text schedule states the dwelling footprint is 236.99 m² and the deck is 61.92 m². However, the visual lot coverage diagram on the same sheet states the dwelling footprint is 228.18 m² and the deck is 60.34 m² (these diagram values correctly sum to the 306.40 m² tota...

Why it matters: Accurate lot coverage and gross floor area statistics are critical for zoning compliance and permit approval. Conflicting area data within the application drawings—specifically old uncoordinated text values conflicting with the diagrammatically derived totals—will likely result in examiner questi...

Suggested next step: Please clarify the correct areas for the dwelling footprint, concrete deck, and garage. Update the 'LOT COVERAGE' text schedule and 'PROJECT STATISTICS' table to be consistent with the lot coverage diagram and the 1st Floor Plan.

RFI draft: Please clarify the correct areas for the dwelling footprint, concrete deck, and garage. Update the 'LOT COVERAGE' text schedule and 'PROJECT STATISTICS' table to be consistent with the lot coverage diagram and the 1st Floor Plan.

Summary: The Foundation Wall Section detail specifies reinforcement with '(INSIDE WALL FACE 1" COVER)'. The specification schedule F3 requires the rebars to be 'PLACED 2" OFF FROM INSIDE FACE.' The drawing shows half the specified cover distance from the inside face of the foundation wall.

Why it matters: Reducing the inside face cover from 2" to 1" shifts the reinforcement position within the wall cross-section, potentially affecting the structural capacity and the rebar's fire resistance and durability. Since the wall is 10" thick, this changes the effective depth of the reinforcement. Construct...

Suggested next step: Request clarification on the correct concrete cover for reinforcement on the inside face of the foundation wall. The specification F3 requires rebars placed 2" off from the inside face, while the Foundation Wall Section detail on A-2.3 indicates 1" cover. Please confirm and re...

RFI draft: Request clarification on the correct concrete cover for reinforcement on the inside face of the foundation wall. The specification F3 requires rebars placed 2" off from the inside face, while the Foundation Wall Section detail on A-2.3 indicates 1...

Summary: The Foundation Wall Section detail specifies 'PROVIDE 15M DOWELS (24" VERT. x 12" HORIZ) @ 32" o.c.' for the footing-to-wall connection. The specification schedule F1 requires 'PROVIDE 15M DOWELS @ 16" o.c.' The drawing shows dowel spacing at double the specified interval, resulting in only half the number of dowels required by the specification.

Why it matters: Dowels at 32" o.c. instead of 16" o.c. provide half the connection capacity between the footing and foundation wall. This reduction could compromise the structural integrity of the footing-to-wall joint, particularly under lateral soil pressure and seismic loads. If constructed per the drawing, t...

Suggested next step: Request clarification on the correct spacing for 15M dowels connecting the footing to the foundation wall. The specification F1 requires dowels at 16" o.c., while the Foundation Wall Section detail on A-2.3 shows 32" o.c. Please confirm the correct spacing and revise the confl...

RFI draft: Request clarification on the correct spacing for 15M dowels connecting the footing to the foundation wall. The specification F1 requires dowels at 16" o.c., while the Foundation Wall Section detail on A-2.3 shows 32" o.c. Please confirm the correc...

Summary: The drawing's FW1 foundation wall note specifies wood studs placed 2" off from the foundation wall with R20 closed cell spray foam insulation. The FW1 wall type schedule in the specification defines the studs as 2.5" off from the foundation wall, with a two-layer insulation system: 2" spray foam R10ci on the concrete face plus 3.5" spray foam R12 between studs (totaling approximately R22 nomina...

Why it matters: The 0.5" reduction in stud offset from the foundation wall changes the available space for the continuous insulation layer on the concrete face, which affects thermal performance and moisture management at the foundation wall. The lower total R-value (R20 vs R22 nominal) and simplified single-lay...

Suggested next step: Request clarification from the designer/engineer on the correct FW1 foundation wall assembly. The drawing notes specify studs 2" off from the foundation wall with R20 spray foam, while the FW1 specification on Sheet A-2.1 defines studs 2.5" off from the foundation wall with R1...

RFI draft: Request clarification from the designer/engineer on the correct FW1 foundation wall assembly. The drawing notes specify studs 2" off from the foundation wall with R20 spray foam, while the FW1 specification on Sheet A-2.1 defines studs 2.5" off fr...

Summary: The 2nd Floor Plan drawing indicates that the main staircase is designed with 10.5" treads. However, the ST1 Stair Schedule in the specifications dictates a maximum tread size of 9-1/4". The drawing explicitly exceeds the maximum dimension allowed by the specification.

Why it matters: Stair geometries are strictly regulated for safety and code compliance. While 10.5" is a standard tread size in many codes, it directly conflicts with the provided project specification's maximum limit of 9.25". This discrepancy will cause confusion during construction and could lead to framing e...

Suggested next step: Clarify the required stair tread dimension. Is the drawing's 10.5" tread correct, and should the ST1 specification's maximum tread of 9-1/4" be revised?

RFI draft: Clarify the required stair tread dimension. Is the drawing's 10.5" tread correct, and should the ST1 specification's maximum tread of 9-1/4" be revised?

Summary: The drawing shows the load-bearing wall separating the garage from the foyer/stairwell area annotated as 'HATCH INDICATE 2x4@16"o.c. LOAD BEARING WALL'. Specification note 05 requires 'R22 IN WALLS' between the house and garage. Standard R22 batt insulation requires a minimum 2x6 stud cavity (5.5" depth); it cannot fit within a 2x4 stud cavity (3.5" depth). Furthermore, the specification's P3 i...

Why it matters: Using 2x4 studs on the garage-to-house wall prevents achieving the required R22 thermal insulation, violating the building envelope energy compliance requirements. The P3 wall assembly also serves as a fire and gas separation between the garage and living spaces. Failure to use the correct framin...

Suggested next step: Request clarification on the stud size for the load-bearing wall between the garage and the foyer/stairwell. The drawing indicates 2x4@16"o.c. studs, but specification note 05 requires R22 insulation and the P3 wall type specifies 2x6 studs for garage-to-house separation. Shou...

RFI draft: Request clarification on the stud size for the load-bearing wall between the garage and the foyer/stairwell. The drawing indicates 2x4@16"o.c. studs, but specification note 05 requires R22 insulation and the P3 wall type specifies 2x6 studs for ga...

Summary: The drawing specifies 25MPa concrete for the exterior retaining wall. However, the general concrete notes in the specification explicitly require 32MPa concrete for all exterior use and/or concrete exposed to freezing.

Why it matters: Pouring 25MPa concrete in an exterior environment subject to freezing exposes the retaining wall to freeze-thaw damage and degradation over time, failing building code durability requirements.

Suggested next step: Please confirm if the exterior retaining wall concrete should be upgraded to 32MPa with 5-8% air entrainment, as per the typical concrete notes.

RFI draft: Please confirm if the exterior retaining wall concrete should be upgraded to 32MPa with 5-8% air entrainment, as per the typical concrete notes.